Science topics: CatalysisImmobilization
Science topic

Immobilization - Science topic

The restriction of the MOVEMENT of whole or part of the body by physical means (RESTRAINT, PHYSICAL) or chemically by ANALGESIA, or the use of TRANQUILIZING AGENTS or NEUROMUSCULAR NONDEPOLARIZING AGENTS. It includes experimental protocols used to evaluate the physiologic effects of immobility.
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I am working on immobilization of peroxidase on magnetic nanoparticles using adsorption. Unfortunately, the change in enzyme activity is very low. Consider the absorbance change over 3 mins for the immobilized enzyme:
2.368
2.381
2.401
And this change for the soluble enzyme:
0.244
0.43
0.594
0.725
So, please what the reason behind that difference and how to fix it, given that I have varied several factors like pH, temperature and [Enzyme] but alas with same consequences.
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It isn't surprising that the nanoparticle-adsorbed enzyme has lower activity than the enzyme in solution. In fact, this is precisely the mechanism that was proposed about 20 years ago by McGovern and Shoichet to explain why some chemical compounds behave as non-specific enzyme inhibitors. They showed that some compounds form nanoparticles that remain suspended in solution, and adsorption of the enzyme to these nanoparticles inhibits the enzyme. Presumably, this is because adsorption causes a structural change in the enzyme, or blocks the active site, or prevents the enzyme from undergoing a necessary conformational change involved in catalysis.
In order to avoid this sort of nonspecific inhibition, you should look for a way to immobilize the enzyme by a flexible linker that allows it freedom of movement.
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Hi, I have always done my in-vitro experiments of protein-antibiotic interaction at a pH of 5.5. Now that I want to do some experiments with the SPR, is it still advisable to use this low pH? Thanks!
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Using immobilization and running buffers at pH 5.5 in Surface Plasmon Resonance (SPR) can have some potential disadvantages.
  1. pH stability: Lower pH values can be more challenging to maintain stable over time, especially if the buffer is not buffered properly. This can lead to measurement errors and inconsistencies.
  2. Protein stability: Some proteins may be less stable at lower pH values, leading to denaturation or degradation, which could affect the binding kinetics and specificity of the interaction being studied.
  3. Immobilization efficiency: Lower pH values may also affect the efficiency of protein immobilization on the sensor chip surface, which could impact the measurement of binding kinetics and specificity.
  4. Interference from other species: Lower pH values may also lead to interference from other species in the buffer or sample, such as protons or hydronium ions, which could affect the binding kinetics or specificity of the interaction being studied.
It is important to consider these potential disadvantages and to test your protein-antibiotic interactions at a range of pH values to determine if pH 5.5 is the optimal condition for your specific system. Additionally, It is also important to check if the immobilization buffer and running buffer that you are using are compatible with the pH you are using.
References:
  1. "Surface Plasmon Resonance: Principles and Methods" by P. R. Unwin and M. J. Rosseinsky
  2. "Biosensors: An Introduction" by B. E. Conway
  3. "Surface Plasmon Resonance-Based Sensors" by T. E. Schäffer and J. Homola
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Should I choose the immobilization method based on the application which I am supposed to do.
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Thank you soo much for your response sir Mohamed Hassan
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Hello
I am researching about immobilized lactase application in the industry. what companies are using the immobilized lactase?
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I need this paper
"PASTORE, M., MORISI, F., VIGLIA, A. International Symposium Mario
Negri Institute. Milan, 15-16 June, 1973."
can you help me?
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I am working on immobilization of peroxidase on magnetic nanoparticles, I want to study the influence of immobilization on pH, Temperature and kinetics of the enzyme. How to do so given that the immobilized peroxidase get precipitated after immobilization?
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You can run the reaction with an immobilized enzyme if you can keep the nanoparticles fully suspended during the reaction, then pellet them quickly (either by centrifugation or with a magnet) and measure product formation in the supernatant. One way to do this is to perform the reactions in microcentrifuge tubes that fit into an Eppendorf Thermomixer (or similar instrument). If the nanoparticles are small enough, they may even stay in suspension well enough without mixing, as long as the reaction time is not too long.
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How can metal ion in soil be immobilized and role of biochar in remediating heavy metals in soil?
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Biochar amendment is a promising approach to mitigate soil contamination via immobilizing heavy metals and organic pollutants. The quality characteristics of biochar as a soil amendment varied greatly with the feedstock materials and the pyrolysis conditions. Soil-incorporated biochar was able to stabilize Cd, Cu, Ni, Pb, and Zn and reduce their bioavailability through enhanced sorption and chemical precipitation. The stabilization efficacy was largely determined by cation exchange capacity, pH, and ash content of the biochar. Biochar amendment increased the mobility of anionic toxic elements in soil. Soil-incorporated biochar was also able to absorb non-polar organic compounds and polar organic compounds. The adsorption efficiency was controlled by the biochar surface properties specific surface area, microporosity, and hydrophobicity. Biochar may facilitate the mineralization of organic pollutants by enhancing soil microbial activities. The effectiveness of biochar-facilitated soil remediation was case specific, changing with the biochar source, amendment rate, placement, soil type, and pollutant species. Biochar reduces soil density and soil hardening, increases soil aeration and cation-exchange capacity, and changes the soil structure and consistency through the changes in physical and chemical properties. It also helps to reclaim degraded soils.The larger surface area and higher surface energy are helpful for biochars to strongly absorb the heavy metal pollutants and remove them from the soil. Possible mechanisms for the heavy metal retention by chars are the formation of metal (hydr) oxide, carbonate, or phosphate precipitates and/or the activation of surfaces caused by the pH rise, and sorptive interactions between d-electrons of metals and aromatic π-electrons of chars, and specific metal.
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I have a material supporting a peroxidase enzymes and I wish to collect the infrared spectrum of the complex support-enzyme, but this system is in buffer medium (citrate-phosphate). The technique available for FTIR analysis is by KBr pellet therefore what is the pre-treatment useful to dry the support with enzyme without degradation of biomolecules attached?
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Experiment this technique:
1. Dialyze the sample against a suitable KBr solution
2. Expose the sample to evaporation under vacuum at low temperature
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I am trying to perform covalent immobilization of streptavidin protein on glass surface. This is done by first coating the glass with 2% APTES-toluene and then with 2.5% glutaraldehyde-water solution. Then I add the streptavidin which is in PBS (pH 7.4) on the glass coverslip. This doesn't seem to work. Please let me know the right pH, salt and temperature conditions that are appropriate for the reaction between glutaraldehyde and amine groups created by APTES coating on glass.
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Some enzymes have high immobilization efficiency at acidic medium while others prefer basic medium or neutral medium. why?
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Enzymes are polypeptides . The Change in pH effects the ionisation state of the side chains of amino acids. The charge on enzyme protein changes.
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I want to know when we use gold electrode and immobilize thiolated aptamer on the gold surface later with living bacterial cells after incubation with 2 concentrations of bacteria I have worst results. How to optimize it?
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square wave voltammetry
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Chicken or Egg?
Considering the outcome of 183 patients admitted to Tongii Hospital in Wuhan in January, mean age, 54 when all patients received supportive care and antivirals. 41% had comorbis chronic diseases. 45.9% remained as inpatients with an overall mortality of 11.5%.
The patients were tested for prothrombin time, activated partial thromboplastin time, antithrombin, fibrogen, D-dimer and fibrin degradation products every 3 days for the first 2 weeks as inpatients. 71.4% succumbed to the virus as non-survivors and 4% showed no evidence of disseminated intravascular coagulation.
Speculation as to whether this is caused by the virus directly has been presented in the news bulletins giving COVID 19 an even more sinister characteristic or may the observed blood clotting be more due to the comorbidity conditions with a pre-existing thrombophilia tendency, than purely COVID 19. A chicken or the egg discussion of this situation needs to be addressed.
Thrombosis can simply occur due to immobility, particularly postoperatively and, although patients are regularly turned intensive care treatment, this level of activity may exacerbate blood clotting complications. Clearly pre-existing cardiovascular conditions are an important factor such as arterial thrombi in MIs and Strokes.
Genetic factors that interfere with the human coagulation cascade are relatively common. Thrombophilia can be caused by a severe deficiency of inhibitors (type I) or a severe elevation of coagulation factors the can be congenital or acquired also arterial, venal or combined. Venal thrombosis can be portal, renal, hepatic, Paget-Schrotter disease (upper extremity) and Thoracic outlet syndrome (unrelated to trauma).
Of the congenital conditions 5% of the population have the Factor V Leiden thrombophilia condition where 95% carting this genetic mutation develop a blood clot during their life.
• Prothrombin mutation (G20210A, 5’UTR)
• High homocysteine levels due to MTHFR mutation
(High homocysteine levels also due to vitamin deficiency B6, B12 and folic acid)
• Factor VIII promoter polymorphism (high FVIII levels)
• Other factors causing blood clotting are autoimmune disorders such as Anticardiolipid antibodies
• Lupus anticoagulants
• Renal disease (renal loss of thrombin)
• Budd-Chiari syndrome
Some rarer coagulation abnormalities include
• Plasmogen and fibrinolysis
• Paroxysmal nocturnal haemoglobinuria (haemolytic)
• Protein C deficiency
• Protein S deficiency
• Antithrombin III deficiency
Lillicrap D. Disseminated intravascular coagulation in patients with 2019-nCoV pneumonia. J Thromb Haemost. 2020;18(4):786‐787. doi:10.1111/jth.14781
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Prof. Annwyne Houldsworth: Please let me ask the following three questions:
  • Is there a lack of interpretability and transparency related to this virus?
  • Did we reach a state with this pandemic that is hard to control and monitor?
  • Is COVID-19 one of nature's secretions or it has been fabricated in the laboratories of one or more countries?
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If I found increase in total distance traveled and reduction in immobile time in open field test with enhanced hippocampal weight can I conclude normal anxiety which is helpful.
In addition, is there is a relation between reduction of Erk, myc, miRNA and serotonin and reduction in anxiety?
Thanks and best regards.
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Quiero hacer especial énfasis, en que si bien la ansiedad patológica o psiquiátrica, debe ser diagnosticada por el buen clínico (pues la psiquiatría es una especialidad clínica), su diagnóstico positivo lleva de la mano el diagnóstico diferencial de las entidades orgánicas que cursan con ansiedad, que de no ser diagnosticadas a su debido tiempo, pueden pasar inadvertidas y, ocasionar discapacidad, cronificación de enfermedades, discapacidad y hasta la muerte, de ahí, el valor semiológico que tiene hacer el diagnóstico de un cuadro ansioso, frecuente en el ejercicio de la práctica médica de cualquier especialidad.
a) Enfermedades endocrinas. Entre ellas destacan: 1) hiper e hipotiroidismo, que pueden presentarse inicialmente sólo con signos y síntomas de ansiedad, en ocasiones persistentes, aunque se compense la alteración tiroidea; 2) feocromocitoma, cuyas crisis se manifiestan con cefalea intensa, sudoración, enrojecimiento e hipertensión arterial; 3) hipoglucemia; 4) hiperparatiroidismo, que se confirma determinando niveles de calcio sérico; y 5) enfermedad de Cushing.
b) Enfermedades cardiopulmonares. Destacan: insuficiencia cardíaca congestiva, prolapso de válvula mitral, embolismo pulmonar, arritmias (p. ej., taquicardia supraventricular paroxística), enfermedad pulmonar obstructiva crónica (EPOC), asma bronquial, apnea del sueño, neumonía e hiperventilación. En ocasiones puede confundirse un episodio de angor péctoris con una crisis de angustia, de forma que es conveniente la realización de un ECG.
c) Enfermedades neurológicas. Entre ellas se distinguen: crisis comiciales parciales complejas, accidentes cerebrovasculares (de córtex frontal, insular o temporolímbico), tumores del tercer ventrículo, encefalitis, enfermedades desmielinizantes, enfermedad de Wilson y trastornos vestibulares.
d) Enfermedades metabólicas (déficit de vitamina B12, porfiria aguda intermitente, acidosis metabólica, entre otras.).
e) Otras (síndrome carcinoide, enfermedades del colágeno, brucelosis y otros).
f) Trastorno de ansiedad inducido por sustancias (cafeína, anfetaminas, corticoides, cocaína, atebrina, quinacrina, insecticidas, epinefrina, aminofilina, teofilina, drogas de abuso sobre todo estimulantes del sistema nervioso central).
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I am trying to immobilize a polysaccharide (MW 900) on microplate but failed and need advise. Thanks.
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ELISA technique can be adapted for measuring the antibody against polysaccharides of bacterial or other origin. However, to my knowledge, it cannot be adapted for a direct determination of polysaccharides.
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I'm working on a manuscript right now that needs a meta-analysis. In articles that show a percentage change in the mobilization of heavy metals, I wish to do a meta-analysis. However, I'm unsure if a metanalysis using percent change is really feasible.
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I have been trying to do that only. Thank you Cory Clark , this was very much helpful.
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Some polymers like polycarbonate, polysulfone, polyetherimide are highly hydrophobic. is it possible to immobilize streptavidin on these polymer surfaces?
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I few have few knowledge about PDMS optical coating layers !
Thank you.
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I am performing esterification reactions with immobilized lipases on epoxy supports. During the first reaction everything goes as expected, achieving great yields of fatty acids to biodiesel conversions. However, during the second batch/cycle there is a huge decrease in the yield of reaction. The lipases are covalenty bonded to my support as I could check with some techniques; so, the explanation may be that the immobilized enzyme is lossing its activity. What could be causing that? After the first reaction, I filtered and washed the support with ethanol and later with my buffer solution and I performed my reactions with ethanol.
Thank you for your help!
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Hi! I am trying to measure the potential nitrification rate (PNR) using the "shaken soil slurry method", following one from Drury et al. 2008. Because of sample limitation, I scaled down the sample and working solution amount to 6g and 40mL. In the past I tried it without shaking the samples during incubation but of course I got useless results with negative PNR. So I tried using a rotary shaker this time. Here is what I did:
1. After putting the soil sample and working solution (made according to the protocol above) in a 50mL tube, I shook the mixture vigorously.
2. Immediately I took the initial 15mL of the aliquot for t=0.
3. I put the rest of the tube on rotary shaker at 200 rpm for 24 hr incubation (I also transferred couple of samples in 125 mL Erlenmeyer flasks, also shaken, for comparison)
4. I added few drops of flocculent solution (CaCl2 and MaCl2) into the aliquot and it was centrifuged at 3000 rpm for 5 minutes and the supernatant was filtered using filter paper
5. The filtered solution was analyzed in SmartChem for NH4 and NO2+NO3
6. After incubation, 15mL of the incubated sample was processed as 4 and 5.
I know that I should have taken multiple samples along the incubation to do linear regression but I am short on materials. After all this, I compared the results among control (no rotary shaker), 50 mL tube incubation, and 125mL erlenmeyer flask incubation. I was expecting some notable decrease in NH4 and increase in NO3 with the later two, or at least the flask samples. However, I see that NH4 did not decrease consistently (some even increase with incubation) and NO3 content even decreased for one of the flask samples. I am really confused why the results would come out like this. Here are my thoughts:
1. SmartChem measurements are being inaccurate? I do see that the NO3 levels are quite low compared to the standards used in SmartChem. Maybe this is creating some inaccurate measurements?
2. Perhaps rotary shaking falcon tubes is not enough to create aerobic conditions throughout the sample, thus leading to denitrification. However, this does not explain why I saw decreased NO3 with one of the flask samples which should have thoroughly aerobic condition.
And here are my main questions:
1. Why would NH4 levels increase with incubation? My understanding is that the conditions of PNR assay should only decrease NH4 via nitrification and immobilization.
2. Is there a way to salvage PNR results riddled with negative PNR? I think negative PNR occurs due to either insensitive measurements or denitrification and NO3 immobilization during incubation. Is there a way to account for the latter possibility in my data?
Can anyone offer to explain???
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Hi,
First, you should use a bigger bottle, if you incubate 6g in 40ml a 50 ml Bottle is to small and you can´t expect aerobic conditions. I would suggest to use 100 ml Duranbottles.
Second, don´t shake the nitrifiers so much. It is better just to use 100 rpm
Third, the initial NH4 concentration should not be higher than 1mM.
Forth, your incubations should be longer, up to one week. Depending on soil type and temperature.
For you Ammonium, Nitrite and Nitrate measurements: I don´t know the SmartChem method. Maybe you should use the classical photometric ones.
To distinguish between net und gross nitrification, labelling with 15N nitrate is a possible method.
Best,
Tina
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trying to immobilize enzyme on nitrocellulose paper.
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Kindly check the reference
Biochemical Engineering Journal 1998 2 (3) 179-186
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The concept of immobility is showing up -- and often in relation to the closures that the pandemic has created. My concern or interest is in the way immobility is used. Often it seems posited as the opposite of mobility (or in other words NOT migration) and that is rather narrow. Immobility is also used to describe the limits on peoples who would otherwise cross national/international borders. Shouldn't internal movement factor into our discussion as an alternative? And immobility is more than not migration, would be interested to hear thoughts on this.
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Max J. Stein , yes, it does show up in discussions of social mobility (immobility) but in migration - it is often approached as what people DON'T do, and while there are links between mobility and immobility, NOT migrating is not the same as being immobile, it has to be more than a physical movement defined by a relationship to a geographic point in time as both Nicolas Parent and Neema Ghenim argue. At an institutional level, if immobility is referenced as NOT mobility, we lose the complexities that drive immobility as a household decision for example.
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An enzyme is immobilized on multiwalled carbon nanotubes (MWCNTs) which were magnetized by filling them with Fe3O4 nanoparticles (to prepare magnetic MWCNTs) . The immobilized enzyme was used to catalyze an acidolysis reaction of a fat with Oleic acid. I was wondering if the Fe3O4 nanoparticles of the enzyme support may get involved in oxidation of the unsaturated fatty acids present in the reaction.
thank you.
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While Fe3+ is a stable configuration, catalytic activity is still possible. Whether it is actually happening in your case, is a whole different beast of a question.
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Dear everyone,
Recently, the immobilization of β-D-Glucosidase on Fe3O4@SiO2 magnetic nanoparticle has been carried out in our lab. The Fe3O4@SiO2 was modified with 3-aminopropyl triethoxysilane to obtain amino functionalized nanoparticle,then activated with 2 % (v/v) glutaraldehyde according literature. However, the  immobilization efficiency of β-D-Glucosidase protein is relatively low(~10%),leading to very low enzyme activity. Can someone show me some advice to improve the immobilization efficiency?
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The immobilization efficiency should be calculated with respect to the surface of the particles. The same is true for the concentration of glutaraldehyde. Are you quantifying the concentration of amine groups on the surface? You could estimate your efficiency using this concentration.
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Protocol on soluble carrier material selection for coating bacteria in order to rapidly reach bottom of ETP for wastewater treatment.
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Dear Divya Jose thanks for sharing this very interesting technical question with the RG community. Personally I'm not an expert in this field, but I just came across the following potentially useful review article which should help you in your analysis:
Polymeric Materials Used for Immobilisation of Bacteria for the Bioremediation of Contaminants in Water
This review has been published Open Access so that it is freely available as public full text (please see attached pdf file).
I hope this helps. Good luck with your work and best wishes!
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i want to know about the ways glucose can be supplied to the system where glucose oxidase is immobilized so that the system becomes stand-alone. kindly help!!
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Good morning Tarun Gangar.
What you seek is basically KNOWLEDGE about...
Fortunately,in this time and age KNOWLEDGE in any field is easily accessible on the Internet.Just key in the major words of the subject and then,presto!!!- you get the answers ~,response.
My caution and guide to you is to verify the source of the information to make sure that it is solid ,reliable creditable etc.
Hoping this helps out?
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I'm working with enzyme immobilization on magnetic supports and I can't find specific protocols for characterization of these supports and enzymes after immobilization by microscopy.
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Dear all, the following documents give detailled experimental procedure in doing characterization of nanoparticles, and the information obtained via each technique. My Regards
10.1039/9781782621867-00001
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For immobilization of serine protease which crosslinker is best?
#protein #crosslinker #immobilazation
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My concern is that i dont wanna use any chemical as crosslinker, I want to use polymer.
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if yes, what is the nature of the interaction between them?
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Dear Komal Grover, better to use the term 'adsorption' than 'immobilization'. In the following review, the mechanism of interaction is discussed. My Regards
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Hi everyone
I am working with enzyme immobilization. I made the immobilization using 10 mg of support with 23000 Units/L of activity, then I recovery from the supernatant almost 70000 units, so my immobilization yield is almost 71 %. Now I want to determine the storage stability over a time period but I don’t understand the protocol. What I did was to storage the immobilized solid suspension at 4 degrees and then I determine the activity every 4 days. But for example, first Activity of the suspension was 5 U/L, then 8, then 10, then 14… how do I determine the storage stability using a relative residual activity?
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I’ve been measuring the supernatant activity. I am not aure how to measure the acruvity of an amount of my solid support since it will make noise on the UV analysis
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After the immobilization of the biomolecules, the value of ks changes due the change in electrochemical peak current. In that case what exactly can be interpreted by this change?
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Thank you Prof. Majid, When we compare different electrodes modified step by step and the ks value differs than what can be interpreted from that data?
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Hi Dear Friends
I immobilized CuO on the surface of CNT via precipitation method.
First I want to know that whether or not CuO functional groups would react with functional groups of CNT? I mean O with O=C-OH?
Or this synthesis just has a physical nature and no new bonds between two materials would form during this immobilization.
Second, I would like to know that except for NMR which can successfully demonstrate this synthesis, whether FTIR can be reliable to show this reaction (if would be)?
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I agree that indeed there can be a set of intermolecular interactions between CuO and CNT functionalities. But, it seems, the degree of interactions strongly depend on conditions of your precipitation method. If it was a typical precipitation from the copper salt by alkali in the presence of the dispersed CNTs followed by calcination at high temperature, then you really oxidized the CNTs and could see this change in their composition by FTIR. To make sure in the interaction you need to compare FTIR spectra of the mechanical mixture of CuO and CNTs and the nanocomposite. Besides, if you really used calcination you could calcinate pure CNTs under the same conditions as the nanocomposite and to make their spectrum after this treatment.
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HI,
I cloned a bacterial protein (19kDa) in pET15 vector, with 6x his tag. After overnight induction at 30 degree C, I sonicated the cells and purified the protein on fresh NiNTA column.
After immobilizing the protein onto the column for 15-30min at 4 deg C, I wash the column 5 times without imidazole (protein got eluted during wash with 20uM imidazole in pilot expt). Even though my last wash is clean, as soon as I add 100uM imidazole, I see proteins start to come out of the column, everything gets eluted by 300-400uM imidazole. Surprisingly I see more than 10-12 bands in my 100uM imidazole eluate, ~5 bands in 200uM eluate and 2-3 bands in 300uM eluate. The intensity of my protein also decreases with each eluate, hence I cannot use the subsequent eluates for my assay.
Kindly help.
Regards,
Kasturi
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Hey Kasturi!
Because some impurities have an affinity to nickel columns - some proteins just happen to have a few surface histidines in close proximity to each other, and they will bind to your column. Further, your protein might also happen to bind to some host proteins that get co-eluted. Generally, you should wash your column with a buffer that contains a low concentration of imidazole (if your protein elutes at 20mM, maybe try washing with 5mM). Further, you can pool your step elutions if they are clean enough and you can concentrate them using something like an Amicon centrifugation concentrator. I would recommend that you then perform a size exclusion chromatography if you urgently need protein that clean for your assays.
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Greetings,
we are currently working on the cultivation of the microalgae Dunaliella tertiolecta. We try to count the cells in a Thoma cell counting chamber under the microscrope. Problem is, the cells move phototactically, thus the counting of cells is inaccurate at best, caused by rapid movement of the cells under a light source.
I'm wondering if anyone knows of a method to immobilize the cells? I'd be very grateful for any suggestions!
Best regards and thanks in advance,
Marius Tölle
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Hello Marius,
When i need to count motile green algae such as Dunaliella or Tetraselmis i use a diluted solution of iodine tincture, just few drops in your sample, but don't exceed or you will have a too bright color.
Otherwise you can prepare the classic lugol solution or a 5% formaldehyde solution
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there is the same commercial protein from two different vendors which use two different descriptive method about receptor-ligand affinity. I can't understand the "linear range", what is the mean.
1. When Recombinant Human SIRPa/CD172a Fc Chimera is immobilized at 2 µg/mL, Recombinant Human CD47 binds with an ED50 of 0.04-0.2 µg/mL.
2. Immobilized Human SIRP alpha, Fc Tag at 5 μg/mL (100 μL/well) can bind Human CD47, His Tag with a linear range of 6-100 ng/mL.
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I concur with Jordan T White that using log-scale would give a better readout of the actual binding affinities. The differences in the layout of the two plots makes comparison of the values difficult.
I would determine the 'linear range' of the upper plot to be between 30 - 250 ng/ml, while the 'linear range' of the lower plot is <5 ng/ml -< 50 ng/ml; above 50 ng/ml, it is non-linear. But just looking at the two plots, the upper one, being sigmoidal, suggest co-operative binding, while the lower one looks like a saturation curve.
Perhaps there is a valency difference in the two proteins? I know that Fc chimeras will form dimerize to form bivalent chains. I do not know if Fc-Tag chimeras dimerize or not. I am unfamilar with that platform.
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WE all know that POM could be immobilized by incorporating them in pores of MOFs? Could we do the same thing with the substituted POM or lacunary poms also? Please suggest some readings.
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POMs come in a variety of sizes, therefore the first step is to find a suitable MOF, keeping in mind the pore size and point of interaction.
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Hi, folks!
Is there any mature approach to immobilize chemicals on the surface of copper plate?
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Dear Yin Li thank you for your kind response and explanation. In that case my suggestion would be to search the "Publications" section of RG for relevant research terms related to your question. It is very important that you limit your search to the most meaningful terms. Here are the search results for "copper-based biosensors" in the "Publications" section:
For example, please have a look at the following potentially useful article:
Superior Sensitivity of Copper-Based Plasmonic Biosensors
This paper is freely available as public full text on RG.
Also please have a look at the following interesting link:
MIPT delivers world's first biosensor chips based on copper and graphene oxide
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A.o.A everyone . i need your suggestions.
I want to work on cadmium immobility by the use of nanoparticles and biochar. In already cited literature the work has been done on wheat and rice plant .use of Zno and Feo nanoparticles with plant based biochar. foliage spray of nanopartciles on plant and biochar application to soil for plant roots. now can i work animal based (manure bichar) instead of plant based biochar? New plant species to work. i want a novel topic for my PhD research work.
Need your suggestions .
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Dear Warda Mustfa thank you for asking this interesting technical question.As an inorganic chemist I'm certainly not an expert in this field. However, I found a few relevant references which might help you in your analysis. For example, please go through the following useful articles in which the use of animal-based biochar is reported:
Immobilization of Lead and Cadmium in Soil Using Biochars Derived from Pig Manure and Suaeda glauca
and
Removal of heavy metals from aqueous solution by biochars derived from anaerobically digested biomass
(see attached pdf file)
I hope this helps. Good luck with your work! 👍
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I've been trying to use 5.5 cp and 45 cp Sodium Alginate for microbial entrapment but the beads are getting fragmented in pH 7 and above. In pH 6, however, they are kind of stable. I have tested with blank alginate beads for all the cases.
I maintain the pH of the media with NaOH and HCl.
And my growth media is mineral salt media which is a minimal media. Carbon source is phenol.
The beads are made from a stock solution of Sodium alginate which is in the carbon free MSM media. And the CaClis made in de-ionized water.
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Phosphate buffer is not a good option for buffering the alginate beads since phosphate itself have a strong affinity to Ca ions bound to alginate. The initial problem might also have arisen from this fact; because the initial media also had the phosphate buffer (mineral salt media is also buffered with phosphate) the beads decay through time. A good alternative is to use non-phosphate buffers for pH control, Good's buffers are good for it (We utilized MOPS for pH 7).
For more info on immobilization see Bickerstaff's book:
Sorry I saw the question 4 years late, maybe it helps for other people.
Have a nice research!
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In one reaction, cyanamide and 1,6-diaminohexan were used to link one compound with the NH2 functional group and the other with the COOH. I do not understand exactly the role and function of cyanamide and 1,6-diaminohexan. Can anyone help me?
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Faezeh Mohammadi Please read the following book (chapter 3; link provided below) for detailed explanation of the proposed mechanisms of action.
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I am trying to develop a uPAD that is similar to wax printed paper based ELISA techniques that have been developed.
However, I noticed that such devices are based on sandwich ELISA by immobilizing an antibody in the test zone as the analyte is then an antigen. I seem to understand antibodies adsorb well (are immobilized well) on paper.
In my case, I want to perform an indirect ELISA such that an antigen would be immobilized in the test zone. After which blocking / washing would be done before adding the sample (containing an antibody which would be the analyte in this case), washing, and then adding the substrate for the colorimetric reaction.
However, I am having difficulty finding information on whether antigens can be immobilized effectively on cellulose; will they be dislodged from the test zone when applying wash and different solutions when running the test?
I appreciate any help on this matter.
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Hey, I am not sure if I understood your goal. But as I have done already Nitrocellulose based ELISA (MBA-membrane based assay) I would recommended to take a look my paperz
Take a look the protacol.
If you need any extra help, DM me.
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I have flat substrates (2 mm x 2 mm) ready to be coated with biotin and then streptavidin. I do have a protocol for such functionalization but only for microfluidic channels. Does anyone have a better idea to coat the surface of flat-square slab other than dipping the it into reagents? Thanks in advance!
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It probably depends on the coating quality you need. If it is not principal you can try a pipettor with a suitable volume (e.g. 0.1-2.5 microliter) to drop a small portion of the solution.
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I am monitoring the degradation of contaminants using immobilized enzymes on carbon support. However, to complete the mass balance of the degraded reactant, I have to perform a mass balance on both the solid and liquid phases. Is there a method for solid-phase extraction (SPE) that can extract the degradation reactants and products without affecting the immobilized enzymes? Previously, I've used vortexing for SPE (for other types of experiments not involving enzymes) but think doing so will also remove the enzyme. Any suggestions are greatly appreciated.
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Please look at the following below links which may help you in your analysis.
Thanks
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I have a large amount of gold wafers each of them bearing immobilized silica nanoparticles of either 200 or 50 nm size. I would like to reuse them as they are extremely expensive. Any idea of how could I remove them?.
Thank you in advance
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The nanoparticles will rapidly dissolve in HF; the borosilicate will be much more resistant especially as it's under the Au. So you have 2 choices:
  • Buy new Au coated wafers
  • Try an experiment on one (or part) or more of the wafers
What have you got to lose? Other than your health - proper safeguards for HF use are essential. All that glisters is not gold...
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I have immobilized an enzyme on the immobilization resin Dowex. How can I determine the number of enzyme units present in the powder form. Is it possible that enzyme assay is performed with powder and enzyme units are reported in units/g instead of units/ml. For example, to perform laccase enzyme assay, 10μL enzyme sample is required and results are reported in units/ml. What if I take 10mg of sample and report the results in units/g by performing the same procedure. If it is possible, then kindly provide the reference document or any other way to perform enzyme assay on powdered immobilized enzyme.
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April 1, 2021
Dear Usama,
Knowing the amount of protein immobilized on the Dowex is not the most important parameter as some of the enzyme protein may have been inactivated during the immobilization process. So you need to measure the activity, not the amount of bound protein.
One approach would be to determine the dry wt of the Dowex/enzyme complex, e.g., mg/mL Dowex/enzyme suspension. For the enzyme assay, add an accurately-measured volume of suspension to your buffer, followed by the substrate. It is important to keep the resin/enzyme in suspension, so incubate with stirring (very small stir bar) at a suitable temperature. At periodic intervals (e.g., 0.5- or 1 min), withdraw measured volumes of the liquid over time and measure the amount of product formed/min. This can be used to calculate the # enzyme units/mL (or per dry wt) of the Dowex/enzyme complex.
I hope this information helps you.
Bill Colonna Ames, Iowa, USA williamjcolonna6@gmail.com
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Dear community, I'm looking for at least one article, where the chemical immobilization of a ex situ obtainedMOFs over textile fibers is reported. The most of papers report the in situ synthesisand growing of the MOFs onto the textiles, I need a report of MOF produced separately, and then anchored over the textile fiber.
I would really appreciate if you can help me, even by telling me there's no article of this issue.
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Have a look here:
There are different projects for the immobliziation of "nano"mof on differnet surfaces. A group in Dresden Germany did some work, but i dont know anymore which group it had been.
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I'm using the commercial GOx activity assay from Sigma Aldrich. I'm testing both commercial GOx just dissolved in PBS and GOx immobilized on my electrode nanomaterials. The absorbance at 570nm peaks at abs value over 1, and it declines over time. I thought the absorbance would increase as more H2O2 is produced then plateau to stay at a high absorbance level? When I took out the plate after the reading, and the hot pink color has turned fainter. Anyone have any insight on why/how this happens? Could something in the well have reacted with the dye and turned it back to the reduced form??
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Yes, I'm using it now for testing GOx immobilized on an electrode with an outer membrane. I centrifuged my electrodes (0.5mm dia wire x ~4mm long) in 100uL of the assay buffer for 10min at 5.2G. Then I transfer to a plate well and add 50uL of the reaction mix. I'm seeing the absorbance on the plate reader increase on all measurements from about 0.04 up to about .4 over about an hour.
I would suggest diluting your GOx in the assay buffer until it falls within the linear range which according to the kit is between 0 and 0.6.
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I am working on heavy metal bioremediation using bacterial isolates. I have immobilized bacteria in 2% sodium alginate then cross-linked in 0.2M calcium chloride for 30 min. I have successfully prepared calcium alginate beads with a diameter of approximately 2.0 mm. These alginate beads were used in a carbonate-bicarbonate buffer (1mM) at pH 9.2 for the heavy metal biosorption. But I have observed that the beads were started to degrade within the 2 days in the buffer. Is there a way to improve the stability of the beads or any other method to immobilize the bacteria for treating the alkaline waste? I need to do biosorption studies in alkaline environments.
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Uday Kumar Banala All the best in your research. It will be a challenge to selectively adsorb uranium from such matrix.
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I want to know what is the most cheap and simple immobilization method that are suitable for biodegradation of wastewater from leather industry, that are polluted with lipids (in lab scale). And i also want to know the most suitable carrier for the method (in lab scale).
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Hi!
We are aiming to bind streptavidin to polyacrylamide surface. The EDC/NHS method bounced on me as a common method, utilizing the -NH2 of polyacrylamide and -COOH of streptavidin. Is there any unconsidered factors that may block this route? If EDC/NHS is viable to immoblise streptavidin to acrylamide, how should the reaction condition be set? Consider the static charge of polyacrylamide and streptavidin ( isoelectric point = 6), which pH is optimistic? Should we use a 2 step EDC/NHS xlk or 1 step?
Thanks!
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You may add 5 % of acrylic acid to your acrylamide. Subsequently, the polymer can be activated by a carbodiimide/NHS mixture.
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i am performing SPR experiment and i am referring some journal and websites they stated regarding coupling buffer and immobilization buffer so ihave confusion about these buffer.
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For amine coupling on a carboxylated dextran chip (CM5) the buffer requirement is that it is free of amines. So PBS, HEPES are good buffers, TRIS not.
For more basic answers see www.sprppages.nl
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Dear colleagues I need some tips about the immobilization of laccase enzymes. I am currently planning to immobilize it in magnetic mesoporous nanomaterials, but I would need some advice on how to proceed to bind the protein to the support.
in advance, thank you very much for your help
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Thank you very much for your help, I will check it!
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Hi to all I immobilized a peroxidase on a new synthesized MOF. The reviewer of a journal paper asked me to consider the inhibitory activity and specific affinity of my immobilized enzyme in the introduction. How I can answer this comment of the reviewer for a journal paper revision? What does it mean? In my opinion, these items are related to biosensors. I reported the influence of immobilization on km in my article but I have no idea about the inhibitory activity.
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The specific activity of an enzyme preparation is the turnover-number (molecules of substrate that an enzyme molecule handles per second) multiplied with the enzyme concentration.
What your reviewer is in effect asking is
  • whether the enzyme might have been partially damaged during immobilisation
  • whether there is any steric hindrance to substrate binding/product release due to the immobilisation.
Any such effect could invalidate your observed Km. However, I am not sure that this belongs into the introduction. Evidence of full activity should be presented under results, and its significance in the context of the paper discussed in the discussion section. An exception would be IMHO if the immobilisation procedure is well established and proven to result in fully active enzyme, than this would be mentioned in the background part of the introduction, with appropriate references. Of course, you'd still have to very that your preparation is fully active, and this should be mentioned under results.
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Dear research community.
I want to study FTIR spectra of Immobilized enzyme on alginate beads before and after biodegradation, do i need to grind the Immobilized enzyme on alginate beads for the said analysis.
A quick response is needed.
Thanks for your attention.
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Kindly see this reference
Procedia Engineering Dec 2013 68
DOI 10.1016/1 prow got 2013.12.200
It will be useful
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Hi, I am going to study the DNA1(21mer) bonding to DNA2(21mer+aptamer conjugated to it(42mer)) through EIS. DNA1 is immobilized on the surface of my gold working electrode through thiol group affiliation to gold.
I am applying EIS in each immobilization step. based on the literature in each step, the Rct increases. But in my case, in DNA2 to DNA1 bonding step, it decreases. Does anybody know what will be the problem?
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Perhaps you could explore your system in other gold electrode (commercial for exemple). I`m not an explanation yet for this fact, I`m sorry Zahra.
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I immobilize fluorescent peptide on chitosan films and when I try to measure the thickness of the film with ellipsometry, the software says that I have a film with 2 nm or less. However, with chitosan films without immobilization of the peptide, I detect a thickness of 20 nm.
I already tried to change the model but it did not work. Is it possible that the fact of the peptide has fluorophores interferes with the measurement? Is it possible that the peptide is absorbing the wavelength?
Thank you so much!
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James E Hanson I always use the same wavelength on ellipsometry and is not variable during the measurement. Thank so much for your time it already helped a lot!
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We are looking to immobilize some of our enzymes on Eupergit beads. I was wondering if you know any commercial supplier of Eupergit beads?
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There are a number of suppliers . Check google search .
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I want to investigate protein interaction by SPR. I want to do amine coupling for ligand immobilization on-chip surface. first, activation of the surface by NHS/EDC, and then injection of the ligand should be done. based on chemistry, activation of carboxymethyl surface by NHS/EDC should be done at pH 4.5-7.2, and the reaction of NHS-activated molecules with primary amines of the ligand is most efficient in pH7-8 (Ref: Thermo scientific), but in the SPR instrument book (Biocare) mention ligand immobilization by amine coupling should be done at pH 1 unit lower than the isoelectric point of ligand due to electrostatic interaction toward the carboxymethylated surface. I get confused! which pH should be set for ligand immobilization?!
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Dear Parastou, I agree with Michael. The Thermo protocol may be the best from a purely chemical coupling point of view. The Biacore protocol favours concentration enrichment of protein ligand close to the surface. Simply try a few different pH values according to the different protocols, and most likely you'll find something that works well. Best, Anders
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Actually I have faced a significant quantity of nanocatalyst loss during immobilization on glass surface. Though I have used ethanol(volatile) to spread the catalyst effectively towards the surface of a glass but somehow found significant drop of catalyst outside the glass.
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For L-B-L technique you need strong binder and pH control, maybe you try with chitosan. You can also try screen printing or dip coating method with TiO2 paste. Ref:
Fabrication of screen-printing pastes from TiO2 powders for dye-sensitised solar cells
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Is there a simple (that is one that requires few and not very exotic reagents) chemical reaction to "activate" or "functionalize" the polystyrene of a simple microtitre plate?
In other words, I would like to add carboxyl groups to the surface of a common ELISA plate to then use ethyl-carbodiimide hydrochloride and N-hydroxysuccinimide to immobilize a target on the bottom of the well.
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Look at the normal ELISA procedure and work on those buffers accordingly !!
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I am doing immobilization of amylase from sodium alginate, beads does not form properly and they are not become hard or melted when separated from calcium chloride solution. please guide me how can i improve my immobilization protocol.
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Add 3-4% solution of sodium alginate prepared in 0.1 M phosphate (sodium) buffer (pH 7) by warming at 50 deg C. Allow to cool to room temperature, then add 1ml of your sterile enzyme stock solution earlier mixed with 9 ml of sodium alginate solution. Suspend drop wise into pre-chilled calcium chloride solution of concentrations say 0.1, 0.2, 0.3, 0.4 or 0.5 M. Gently stir mixture at 4°C for 2 h. Recovered beads formed by filtration and wash with distilled water. Store beads in 0.1 M phosphate (sodium) buffer (pH 7.0) at 4°C.
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The soils which are haiving high C:N ratio will be beneficial for agriculture or not. Here i want to know the what is the ideal C:N ratio of the soils for better crop growth & yields.
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Different crops can grown in different soil. Some thrive better when stressed. That said, in general the balancing of Carbon and beneficial soil microbes to achieve an ideal Carbon to Nitrogen ratio of 24 : 1 has been generally considered good. This increases the organic matter and creates an environment of high productivity. I would though focus on whatever crop you are studying and different plans thrive in different environments and stress.
Additionally, I also found this link that summarized some discussion of C:N ratio and its impact on soil.
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What is the minimum Nitrogen content for a Plant to check immobilization loss ?
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Thats a difficult ask Saurabh....if you are talking of plant nitrogen , its plant physiology and perenniality that decide , how much n is to be mobilized and how much to be redistributed towards active sink sites....
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Can crude enzyme be utilized as immobilized enzyme for industrial application if the crude enzyme shows high activity?
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Yes, you can utilize a crude enzyme extract for immobilization. I complete agree with Carlos Vera, you can go ahead and prepare CLEAs for the enzyme of your interest.
Please find the recent paper from my research group.
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What is the minimum Nitrogen content for a Plant to check immobilization loss ?
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Waiting for your response
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I am planning to perform an antibody-ligand interaction study with SPR/Biacore. The idea is to immobilize my antibody with Protein A/G. It would be great if you could share your comments, what to consider, advantages/disadvantages of Protein A/G immobilization for SPR.
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I recommend you to buy the protein A sensor chip instead to made your own protein A sensor chip. Because some signal drift could be observed after the amine-coupling of protein A. The protein A is commonly used compared to protein G.
For my personal experience, I prefer to use the igG kit or Fab kit using a regular CM5 sensor chip. Using this kit you are not worry about the regeneration buffer and these kits show reproducible data.
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I'm looking for a simple and quick way to immobilize Drosophila isolated CNS before Ca imaging without movement disturbance of the brain due to liquid containing stimuli application on it...
Any idea? tips?
Thanks.
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Alternatively, you can use Microfluidics systems to immobilize the whole larva for CNS imaging, while the larva is fully intact.
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Why immobilized enzymes have better pH and temperature resistance?
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Hi Yaaser Q Almulaiky,
According to the question, I would like to place my point of view regarding it:
The immobilized enzyme activity generally depends upon the type of support (immobilization medium) it has. When an enzyme is immobilized, then its microenvironment conditions gets changed in terms of conformational change in enzyme structure. Consequently, there will be change in its denaturation activation energy (Ead), I.e. Ead will be increased which makes enzyme more resistant to different thermal conditions. If we analyze it in a subtle way, As enzymes has different forms, some are dimer or polymeric as well in respective to their subunits. (There must be immobilization of enzyme properly in accordance to its subunits, otherwise it may fluctuate the optimum stability condition). The immobilized enzyme subunits acts as monomers (doesn't dissociates), nevertheless shows good stability with the immobilizer. Similarly, pH conditions works. Example, FTase (fructosyltransferase) enzyme shows good stability under pH 6 from its general stability level (pH 4.5). Similar kinds of points have been evaluated to justify the stability and working mechanisms according to the methodology and some calculations.
I hope this will help you to clear some of your doubts.
Thank you,
Regards.
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I would like to immobilize boronic acid (3-APBA) solution on Grade 4 Chr Cellulose Chromatography paper. Which technique I should do?
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Boronic acid might be immobilized onto cellulose paper via cross-linking which is an irreversible method done by the creation of intermolecular cross- linkages between the molecules of the enzyme by covalent bonds.
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Dear researchers, Some author has a reference describing a process to bind or another method for immobilization of glucose isomerase?
I wishto thanks for every one who may send me a work abbording this theme.
With regards
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obrigado!
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Dear All,
I am working on research related to fabrication of glucose biosensor by using screen printed carbon electrodes (SPCE). I modified the working electrode with nanocomposite and then immobilised glucose oxidase-glutaraldehyde mixture on the modified SPCE.
Here are the detailed steps:
1. Preparation of nanocomposite.
2. Mix 20 μL of the 2% glutaraldehyde solution with 50 μL of Glucose oxidase. The mixture was allowed to sit for 30 minutes at room temperature before use.
3. Drop cast 3 μL of the nanocomposite onto the working electrode (WE) of SPCE.
Immobilization of Glucose oxidase-glutaraldehyde mixture:
1. Drop cast 3 μL of glucose oxidase-glutaraldehyde mixture on the modified SPCE
2. Allow the solution to adsorb onto the modified SPCE for 24 hours at room temperature.
3. After 24 hours, wash the unbound glucose oxidase from the working electrode using 0.01M PBS (pH 7).
4. Let the SPCE to dry at room temperature.
The MSDS mentioned that optimum storage temperature of glucose oxidase is -20°C.
As I am performing the immobilization of Glucose oxidase-glutaraldehyde mixture at room temperature for 24 hours, will it affect the stability of the glucose oxidase?
Plus, should I be storing the SPCE with immobilised glucose oxidase at room temperature or at cool temperature (probably 4°C)?
Help appreciated!! Thanks
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-20ºC is the recommended temperature when the GOx enzyme is under a solid and dry form especially when you are considering long term storage (see paper attached).
Performing the immobilization of GOx at room temperature for 24 hours could affect its activity but, as Siba Moussa mentioned, glutaraldehyde could help its stabilisation.
Working with GOx and biosensors, I recommend a storage (immobilisation process) at 4ºC especially because the GOx is dropcast within a solution.
I hope this helps.
Best regards,
Marie B.
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I'm doing enzyme immobilization right now and I want to calculate the effectiveness factor, η based on this formula:
η =Vmax of immobilized enzyme/Vmax of free enzyme
Vmax to be put inside the formula above must come from one substrate concentration. But how to calculate Vmax from only one concentration of substrate? Because the usual way that I know, to calculate kinetic data including Km, Vmax, a varying substrate concentration is needed.
There's one paper I'm referring to and I don't know how they did that.
Is there any other way to calculate effectiveness factor?
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We can use an overall effectiveness factor to help us analyze diffusion, flow, and reaction in packed beds especially considering a situation where external and internal resistance to mass transfer to and within the pellet are of the same order of magnitude. We can define an overall effectiveness factor that is based on the bulk concentration.
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Dear experts,
Liquid carbon dots (CDs ) were synthesized with greenish color under UV-light. However, after mixing with PVA polymer, the color turned to blue with enhanced quantum yield (QY). what is the possible interaction made this enhancement? Is it related to hydrogen bonds of PVA or other reasons. Thanks in advance.
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Look carefully at your data. since You list quantum yield, I assume the color is fluorescence. Was the original fluorescence green or a combination of blue and yellow - but now the yellow is gone? If it is a shift in the color from green to blue (higher energy, greater difference between the excited and ground states), either the ground state is stabilized or the excited state destabilized.
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I wonder if it would be fine to try some test of encapsulation of oligonucleotides on or within the surface of porous silica gel (60) based TLC films, literature says it is posible to do, but, are there any protocol or directions to take into account?
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Thank you very much!! I am new in doing it so, I realize it is necessary to review some literature. :)
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Hello, I have seen that the oligo modification Amino-C6 [AmC6] Amino-C12 [AmC12] is supposed to immobilize the oligo. How does the principle work?
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A primary amine can be used to immobilize an oligo to a surface that is derivatized with carboxylic acid groups using a carbodiimide such as EDC to form an amide bond between them.
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The peptides have a very high specific signal to the target antibodies on the ELISA assay, but it did not work well on the NC membrane. The peptide was immobilized on the NC membrane with PBS buffer. I would like to ask any strategies which can improve the peptide affinity on the NC membrane assay. Is there any amino acid sequence that can be improved binding efficiency, spotting buffer and/or recommended size of peptide?
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I'm trying to immobilize cellulase on Fe3O4 magnetic nanoparticles coated with Tannic acid, with glutaraldehyde as cross-linker. After the immobilization process, I washed nanoparticles four times and measured the protein amount of washing water with both Lowry and Bradford methods, with BSA as standard, but it is more than the protein amount of initial enzyme I added and the protein loading is negative. I calculated protein this way:
protein loading(%)= protein immobilized onto nanoparticles / amount of protein used*100
Enzyme immobilized onto nanoparticles (mg) = amount of protein used (mg) – the amount of protein in washing water (mg)
total protein of washing water (mg)= protein (mg/ml)* the volume of washing water (ml)
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First of all I would make the calibration for Lowry or Bradford using cellulase itself, not BSA. The slopes may differ a lot for different proteins. Secondly, the enzyme is diluted strongly in the washings, which may be a source of error, too. Consider to concentrate the enzyme in the washings using ultrafiltration membrane, to the volume of starting reaction mixture and then measure both protein concentration and enzyme activity. Finally make sure that no glutaraldehyde or tannin is leaking from the carrier. These may affect protein estimation, at least with Bradford.
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Hello Everyone
I know EDC has been proven to activate the carboxyl group on the substrate to attach amine-terminated particles.
In my work, I have carboxyl-terminated particles that I want to attach to the amine-terminated glass.
My question is Can I use the same protocol of the EDC?
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Dear, Initially couple appropriate linker to carboxylic group and attach amino group containing nanoparticles. Carbodiimide can activate carboxylic group.
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The news in question is very revolutionary: Only an authority can help in such a case. Can a reader be so kind as to inform an authority if he or she happens to have the contact?
The news is that Zwicky was right in 1929 with his early explanation of the Hubble law. Cryodynamics, the now 9 years old sister discipline of the fundamental science of Thermodynamics, is the good news. But the world is too immobile to understand fast enough after its having failed to understand Zwicky for 3 generations.
The word needs to be spread that Einstein overlooked a fourth giant implication of his maverick "equivalence principle" of 1907. Fritz Zwicky first saw it and applied it correctly to cosmology in 1929. However, bad luck wills that the 91 years long IQ blunder of humankind -- of having failed to understand Zwicky 1929 -- entails geocidal consequencesas was first shown in a little paper in 2008.
Is there really no one able to heal a 91 years long dark age which now entails geocidal consequences ever since 2008?
Jan. 22, 2020
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Thank you, Farrukh!
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Recently I got a question which asked the minimum Nitrogen content for a Plant to check immobilization loss ???
Generally a Plant constitutes about 1.5-2% N in their body,which synthesized in their body in organic form.
Immobilization is a phenomena which implies Changing form of Inorganic to Organic & making one nutrient available form to unavailable form in Soil.
Then how is this possible for a Crop to control a phenomena which is occurring on soil by it's own N content ???
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