Questions related to Phosphates
I performed a phosphorus analysis from a phosphate rock sample. For this, I took 0.50 g of a sample which I boiled for 1 hour in a mixture of 15 ml HNO3 and 10 ml HClO4. After an hour, I added 50 ml of water to this mixture. I obtained After boiling this mixture, I added 5 ml of water to finally obtain 50 ml of the sample. Then I took 1 ml of the above sample and added 9 ml of water to form a research sample. So how do I calculate the results of the analysis? (ICP-OES)
We are planning to run it through HPLC with water methanol so as to see if that works.
Hi there! I am trying to quantify total inorganic phosphate from plant samples using a spectroscopy based techniques. I am facing issue with the standards. I have not tested the samples yet. For the first 3-4 standards, the coloration and absorption curves are linear but for standards with higher concentration the color is drastically reduced and curves drops rapidly. I independently repeated it thrice but got the same pattern. Do you have any suggestions to help troubleshoot this issue? Or, what protocol do you use? We are not interested in getting high resolution quantification data for phosphate amount in the samples, so we are looking for protocols which doesn't require sophisticated instrumentation. I have attached the protocol being followed in the attachment below.
I want to dissolve Nile red solution for studying lipid in plants fluorometrically, the protocol suggests dissolving it in 50mM PIPES buffer (pH 7). Can I use any other buffer instead of PIPES?
I am having issues ligating my plasmid vector with my insert fragment due to self-ligation of the vector, which I assume is due to digesting it with one restriction enzyme (NcoI). I have tried double digesting it using NcoI and HindIII, but I am now struggling to purify the digested plasmid from the gel (I get a reading of 0 ug/mL from the nanodrop every time). I have thought to use a phosphatase treatment to prevent vector self-ligation, but I have read that the fragment needs to contain a 5' phosphate for this to work. Will digesting the amplified fragment with NcoI restriction enzyme introduce a 5' phosphate group into the fragment? Any advice would be greatly appreciated!
Recently I am working on oligonucleotide. I have a fluorophore tagged DNA for my experiment. My DNA is tagged with 6-FAM at 3' end. It is suggested that FAM tagged DNA should remain in solutions with 7.2 pH or higher to limit degradation. There are TE buffer or PBS which can be used to dissolve it. For my experiment I want to avoid EDTA and salt actually. But to maintain higher pH ,I have to go with a buffer solution. Now my question is:
Can I use phosphate buffer of pH 8 instead of TE buffer or PBS to dissolve this FAM tagged DNA?
If any other buffer solution will be useful, then please suggest me.
I am performing antioxidant assays ( ApX, GPX, SOD, CAT) in wheat crop.I have extracted the crude enzyme using phosphate buffer, and as per protocol of antioxidants, we can crush the samples using phosphate buffer and supernatant can serve as common enzyme extract for all the assays. In a single day it becomes bit difficult to take the readings of all assays. Can we store the crude enzyme extract in -20 and later use it for antioxidant assays?
I am currently restarting my work on battery management systems, I plan to use Lithium Iron Phosphate cells for their better energy density and relatively better resistance to thermal behaviour than few other commonly sought after battery chemistries. I require some help with good materials or references to help me accomplish BMS for 2W EV. I see that there are Kalman filter based estimations available, but they seem complex and expensive in terms of computations such algorithms require to be implemented.
Kindly request the experienced fraternity to guide me to understand and implement SOX estimation for LiFePO4 Cells.
Thanks in advance.
I am trying to figure out through what means Acetoacetate may be converted to acetate naturally within a healthy, or cancerous cell (though specifically non-hepatic cells). I am especially interested in any methods which involve the TCA cycle. I have been currently considering acetoacetate converting to acetyl phosphate then acetyl phosphate to acetate within the mitochondria; however, I do not know if this is a possible pathway. Any information upon potential pathways for this conversion, or how viable the acetyl phosphate pathway is would be greatly appreciated.
I have always used PDBsum to do a quick look at Ligplot and Nucplot outputs to see which residues in a protein are interacting with a ligand or with DNA. However, I recently found out that sometimes the Nucplot output isn't completely reliable - for the complex structure 6JBX, for example, all interactions are shown as if they were water mediated, which is not the case - there are many direct interactions between residues in the protein and the DNA double helix in the structure.
Are there other options for software that read a PDB file (or webservers that take a PDB code) and report which residues are interacting with DNA (ideally if they specify if the interaction involves the base, the sugar and/or the phosphate)?
I am trying to determine the available phosphate content in a commercial fertilizer. I need a lab protocol (methodology) to carry out the test
I prepared a Phosphate Solubilizing Media in
200ml distilled water with
Tricalcium Phosphate (0.25gm/200ml),
The flask was kept in a shaker with a magnetic stirrer while adding the above components to make sure all the components dissolved properly. After it was dissolved properly, pH was adjusted to 7 and autoclaved. After autoclaving, it was found that the bottom of the flask had clotted media unfit for plating. Is this case normal? How can we minimize this? I repeated the above process twice and got the same results.
In our lab, we developed a combined method for assay and purity of Naproxen, both acid and sodium.
The mobile phase composition is really simple: a phosphate buffer pH 3.0 0.02M and methanol in a gradient from 50/50 to 72%organic in 23 min. The column is a common Kinetex C18 150mm. 4,6mm 3,5mcm.
The extraction spectra are at 230nm for purity and 272 nm for assay. We validated on a Shimadzu Nexera X2.
The sample-set is structured as follow:
5inj of purity std ( SST)
5inj of assay std ( SST)
n°samples ( stability of solution 48H at RT)
3inj of purity Std ( as control)
3Inj of assay std ( as control)
The carry-over issue has been observed during the transfer to the CQ dept., on their equipment ( Shimadzu 2010 and water alliance ) a carry-over of 2000 to 4000 mAu was visible in the bank before the control std. This carry-over has also impaired the accordance between purity standard ( SST) and purity std (control). As a result, the area has a delta higher than 5%.
Several attempts have been performed to control this issue, first of all with an extensive needle wash (2ml) inside and outside with a mixture of water/methanol 90/10 ( lower % of water do not work) and with a cleaning of the injection system ( available only on Shimadzu).
At first glance, the problem seemed to be solved or at least controlled ( better on Shimadzu than Waters), but randomly, it comes back.
Did anyone face something similar?
IN attachment are the profiles of a clean blank, a blank with carry-over and purity std.
Hi there! What temperature would be the best to store Isocitric dehydrogenase (NADP) stock solution at? The vendor recommends -20C for the powder but is it the same for dissolved NADP in phosphate buffer or should I do -80C?
Thank you for your help in advance!!
What type of phosphate buffer is suitable for extracting protein from the plant
I intend to extract and measure protein from plants by using the Bradford method. In order to do this, I need a phosphate buffer.
Can anyone tell me what kind of phosphate buffer and pH level I should use?
Thank you in advance!
I have a different research-related topic, but I'm considering a nitrate, phosphate, or potassium fertilizer.
I have sodium phosphate dibasic heptahydrate and sodium phosphate monobasic monohydrate and also the anhydrous forms. I want to know the preferred solutions to use and method of preparation
I need to develop a method for the detection of oligonucleotide (2-5 mers in length) in liquid chromatography-mass spectrometry. It shouldn't have any salted buffers, TEA, TFA phosphates as solvents. Those are the requirements of my system. Could anyone suggest any article for such a method?
I am trying to differentiate isogenic pairs of iPSC (derived from Trisomy 21 patients) in cardiomyocytes for the last couple of months but failed. First, I thought it could be the toxicity of the free base form of CHIR99021 and I have replaced it with hydrochloride form but still, I got complete cell death during concentration optimization experiment and noticed that cells without treatment ( without CHIR and exposed to only RPMI+CDM3 supplemented base media) also died. CDM3 is generally made of recombinant human Albumin and Ascorbic acid -2 phosphate. We are suing mTeSR plus for iPSC maintenance media. So, I am really stuck with this condition. I will really appreciate it if anyone can help me out or suggests something.
I am trying to remove phosphate from wastewater sample and also recover them. Is there any material that only absorb phosphate from water? Therefore, which natural material should be appropriate to use as absorbent?
I haven't seen any paper discussing the effect of phosphate concentration on struvite precipitation. All papers majorly discuss the molar ratio that affects the overall struvite precipitation efficiency. I need to know from the literature what is the optimum P concentration for struvite precipitation? How high I can go with P concentration?
Could anybody suggest research articles that used the MATLAB software in environmental catalysis (i.e. reduction of water contaminants nitrate, bromate, sulphate, and phosphates in batch and continuous reactors)?
Thank you in advance!
For Inorganic phosphate determination usually ammonium molybdate and aminonapthosulfonic acid are used. The reaction finally produces a bluish colored complex and the absorbance is taken at 660 nm.
My question is why the absorbance is NOT measured at 450 nm but at 660 nm? The complex develops similar color to that of Blue (450 nm) and not Red (660 nm). So why theories suggest to measure the absorbance at 660 nm?
I am currently trying to make a buffer for protein expression. According to the article, I am to use a buffer with 50 mM NaxPO4, pH 8 (and 0.5 M NaCl).
How do I make the NaxPO4 buffer?
I have previously made phosphate buffers from cold spring harbor protocols https://doi.org/10.1101/pdb.rec8303
(Mixing aliquots of 1 M NaH2PO4 (monobasic) and 1 M Na2HPO4 (dibasic) aliquots to get the desired pH and concentration.... Is this the same buffer, just with another name? Or what to use to make NaxPO4?
I started working on struvite crystallization, and therefore, would you please guide me the about the experimental procedure/literature, which I could follow ?
started with Synthetic water: I tried myself in the lab, pouring salts of Mgcl2, NH4cL, NaH2PO4 (keeping the molar ration 1:1:1) in 100ml distilled water and then I noticed the Ph. range was already in the required struvite range PH> 7.5 But there was no crystals found.
What am I doing wrong ? Please guide.
In order to manage drought due to prolonged dry spell in the presence of crops, there are different techniques are available to manage the situation. Some of them are seed treatment with potassium dihydrogen phosphate or Potassium Chloride, foliar spraying of PPFM fungi, KCl (1 %), humic acid and amino acid etc. Among these product which one is good.
I am working on a chemistry lab report that revolves around the relationship between coagulant dose and its effectiveness at coagulating orthophosphates in lake water.
One of my theoretical questions is as follows:
Calculate the dose of coagulant in mg·L -1 , if the alkalinity of the water before treatment was 5 mval·L-1 , and its acidity was 0.4 mval·L-1 , and the pH of the treated water after coagulation with AlCl3 must be neutral (pH 7).
We perfuse our mice with PBS followed by 4% PFA, harvest brains and allow to fix overnight (20 hours) in 4% PFA before moving brains directly into 30% sucrose for 24-48 hours until tissue has sunk. Then the brains are frozen on dry ice into OCT and sectioned in a cryostat. The 20um sections are kept long term via free floating in a 24 well place immersed in our cryoprotectant recipe below:
STEP 1 Prepare PB (0.1 M phosphate buffer pH 7.2)
1. Prepare sodium phosphate dibasic stock (0.5 M Na2HPO4) by dissolving 35.5 g of sodium phosphate dibasic in a final volume of 500 mL of H2O.
Some crystallization will occur when the solution is stored at 4ºC. Warm on a hot plate and stir until the crystals dissolve.
2. Prepare sodium phosphate monobasic stock (0.5 M NaH2PO4) by dissolving 30 g of anhydrous sodium phosphate monobasic in a final volume of 500 mL of H2O. For NaH2PO4.H20, measure 34.5g.
3. Prepare 0.1 M sodium phosphate dibasic: Put 80 mL of sodium phosphate dibasic stock (0.5 M) from Step 1 in a beaker and add H2O to give a final volume of 400 mL.
4. Prepare 0.1 M sodium phosphate monobasic: Put 30 mL of sodium phosphate monobasic stock (0.5 M) from Step 2 in a beaker and add H2O to give a final volume of 150 mL.
5. Bring the 0.1 M sodium phosphate dibasic solution from Step 3 to pH 7.2 by adding as much as needed of the 0.1 M sodium phosphate monobasic solution from Step 4.
The resulting solution is 0.1 M phosphate buffer pH 7.2.
STEP 2 prepare Cryoprotectant (Use for Immunofluorescence)
To make 1000 ml cryoprotectant
• Sucrose ----------------------------- 300 g
• Polyvinyl-pyrrolidone (PVP-40) --- 10 g
• 0.1M PB ----------------------------- 500 ml
• Ethylene glycol --------------------- 300 ml
Add PVP-40 to 0.1M PB. Stir to dissolve. Slowly add the sucrose to dissolve, and then add the ethylene glycol and bring the final volume to 1000 ml with 0.1M PB. Store at -20°C.
I am looking to know how this cryoprotectant can affect tissue overtime for lipid based targets, specifically MBP? For our longer kept tissue ( > 1 year) we are having an unsucessful time staining for MBP via IF and the black gold II kit. I have suspected the cryoprotectant for a long time, seemingly the longer kept tissue doesn't stain as well; When i compared floating sections kept in cryoprotectant vs directly adhered sections, dried and then stained, the color outcomes for the black gold kit were very different. Directly adhered had more dark purple/blue/red while the tissue that had been exposed to cryoprotectant was more black/grey (diverging from expected color results but still identified tracks appropriately).
We have tissue that can't be recollected and i need to figure out how i can save the tissue currently in cryoprotectant for myelin staining. Neither IF myelin nor black gold II kit staining is working on this older tissue, which we should be seeing ample amounts of ( by WB analysis of mice collected from this group, myelin is ample) but staining will work on more newly collected tissue exposed to cryoprotectant.
Does anyone have any suggestion or publication about the effects of this type of cryoprotectant on targets post fixation? I was wondering if the direct immersion in 30% sucrose was an issue but again, this appears to be an "over time" problem for our sections.
In soils normally the erosion losses of soil phosphate -P are considerable and they are monitored.The leaching losses are presumed to be negligible. Under what soil crop conditions the leaching losses of phosphate are considerable and need monitoring?
Hi everyone, I want to prepare a sodium phosphate buffer of 0.02 M (pH 7 and 7.8). Could you help me, please? I want to prepare this solution by using di-sodium hydrogen phosphate dihydrate (177.99 g/mol) and Sodium dihydrogen phosphate dihydrate (156.01g/mol).
I am performing BSA callibration curve with BSA but I am not getting nice callibrstion curve, just random points. I prepare concentration line by weighing BSA powder (from 10 microg/ml up to 2milig/ml) and dissolving in phosphate buffer pH 7.15. Then I mix BSA sample with Beadford reagent in plastic cuvette (500 ml BSA sample, 500 ml Bradford, 1ml total volume). I tried various BSA volume mixed with phosphate buffer(10, 20, 250 and 500microL and 500microL of Bradford), 10 min incubation in dark and then UV-Vis at 595 nm…I tried two Bradford reagents, so its not old…
Do you have any idea why I am not getting good callibration line?
I normally wash my phosphate and TCAA buffers with dichloromethane (DCM). For the first time, yesterday, I added 10% DCM to the phosphate buffer as usual and a weird thing happened. The DCM turned purplish-pink. It did settle out at the bottom of the bottle but maintained this strange coloration even after an hour. The buffer solution itself was clear and clean. Has anyone experienced this before? What could be behind this observation?
The protein is in phosphate buffer pH 8 and when i try to decrease to ph7 it aggregates.
Is a virus envelope protein with 42 Kda and it is fusogenic. I want to do some NMR experiments with this protein, and i can decrease pH in low concentrations like 5 uM. But when i concentrate to 300 uM it aggregates.
Thank you all!
According to Alshahri et al. (2021), generates liquid ferrate with two different yields (20 and 58%) through wet oxidation of ferric iron by hypochlorite in alkaline medium.
In order to determine the liquid ferrate concentration, is used a Phosphate buffer (5 mM Phosphate / 1 mM, borate: pH 9.1), this buffer is made by adding 27.6 g powder sodium phosphate (NaH2PO4⋅2H2O), 9.5 g powder sodium borate (Na2B4O7⋅10H2O) and 8.5 g of NaOH in 1 L of Milli-Q water, and mixing thoroughly for 2 h.
Then the liquid ferrate is diluted by adding 2, 1, 0.75, 0.5, 0.25, 0.1, and 0.05 mL liquid ferrate into 7 tubes containing 30 mL of phosphate buffer solution.
According to the paper, the absorbance of the liquid ferrate was more likely measured at 510 nm by the use of a UV/vis spectrophotometer.
The concentrations of liquid ferrate (M) was determined by using the following equation:
B =Abs./εC (eq.1)
Where B is the concentration (M); Abs. is the absorbance at 510 nm; ε is the extinction coefficient; and C is the cell path length (1 cm). ε determined at 510 nm as 1150/M cm at pH 9, and 520/M cm at pH 6.2
The yield percentage of liquid ferrate was determined using the following equation:
Yield of liquid ferrate = (B*Dilution times/ Molarity of ferric chloride)*100 (eq. 2)
So my doubt is about which of the absorbance value (which one of the 7 tubes containing liquid ferrate dilutued in a buffer solution) has to be use in eq.1 in order to use the result on eq. 2
I have a sample with magnesium, potassium, phosphate and water. I have found a peak around 3750, is it possible to consider magnesium with OH bound in IR for this peak?
I'm trying to make a solution for haptoglobin measurement using this product. My method gives me the following directions:
0.6g o-dianisidine, 13g sodium phosphate monobasic and 0.5g EDTA dissolved in 1l deionised water, pH adjusted to 4.1.
I know that o-dianisidine is only slightly soluble in water (60mg/l) but possibly more soluble under acidic conditions however it still did not totally dissolve when at pH 4.1
If I dissolved in alcohol, approx (50ml) does anyone know if the addition of the alcohol to my buffer will affect the assay result ?
Anyone have experience with this colorimetric assay for haptoglobin? solving the same amount in
I'm determining the phosphate stabilization potential of some bacterial isolate.
Bacterial cultures were grown in NBRIP medium and after centrifugation, I need to extract the P in the solution before proceeding with the test for available P.
I need to put energy balance for a Rotary dryer . the input feed contains the mixture of mono & di sodium phosphate and H20 (Mass flow rate and Temperature are known). Hot air is used to dry and calcinate the feed (400Deg C& mass flow rate known) to form STPP (mass flow rate & T is known). The hot air outlet temperature is unknown (Mass flow rate is known). I need to know the specific heat value to find the temperature of the outlet hot air stream and to put energy balance
Recently, I have been studying the interaction between plasma proteins and some selected drugs. All measurements were performed on Malvern PEAQ-ITC at 37 °C in 25 mM phosphate or HEPES buffer 7.4 with 150 mM NaCl. My protein concentrations in sample cell are in the range of 100 - 300 μM, while the drug concentrations in syringe are 1-5 mM (depending on the binding affinity). Furthermore, in all previous interactions, it turned out that N is less than 1, more precisely 0.3 - 0.5 on the drugs measured so far, while the thermodynamic parameters are in agreement with previous studies. Since it is mentioned in the literature that protein, e.g. alpha acid glycoprotein, has one binding site for ligands, what are then possible outcomes of low N-values? How to improve it?
Raw ITC data shows binding with a binding constant in the range of 1 - 50 μM, with hyperbolic curves for all measurments. Due to low affinity, it is hard to get some nice sigmoidal curves.
I have played with some different variations of concentration, although not with all possibilities due to expensive protein, to get a higher N (or better, because some say that low N doesn't really mean that experiment is bad?), but it didn’t really help.
The protein concentration was determined spectrophotometrically, and the ligand mainly based on weight.
I also performed the same experiment with one drug according to the published article but I didn't get the same N as them, mine was almost twofolded bigger.
I would appreciate any suggestions, thank you in advance.
I'm currently writing my bachelor thesis and I have a problem with the reaction between TMB (3-3´-5-5´-Tetramethylbenzidine), H2O2 and acetylthiocholine. At this stage I'm not yet adding the enzyme. According to various papers, a blue coloration should already occur after 7 minutes, but in my case it takes several hours. I use a phosphate buffer (pH 7.4) and a citrate-phosphate buffer (pH 5). After adding acetylthiocholine iodide in different concentrations and the phosphate buffer, the plate is incubated at 37°C for 15 minutes. After incubation, the TMB-H2O2 solution is added and measured on the ClarioStar for 60 min.
Does anyone have experience with this assay and has some answers for me?
Thank you in advance.
The end-user has raised a concern related to the appearance of black spots on oxyclozanide tablets. what could be the reason for this?
we are not using any phosphate (DCP/TCP) during the manufacturing process and the substance is also not hygroscopic.
Can anyone guide me how could I prepare this buffer? Should I first prepare 50mM potassium phosphate then 2 mM ethylenediaminetetraacetic acid (EDTA) .Then I should mix them and pH should adjusted by 50 mM sodium chloride (NaCl)?
Respected sir/ maam i am preparing nanoparticles niosomes but the buffer i used is precipitated continuously , how i can resolve this issue?
Storage condition = Room temperature
I synthesized Hydroxyapatite by wet chemical precipitation process with the help of a phosphate and calcium precursor and maintaining the pH of the solutions after mixing at different values using an alkali solution. I found that the percentage yield of hydroxyapatite varies with varying pH values while rest of the synthesis parameters were kept constant throught the synthesis process. What may be the exact reason for this variation in the yield of HA with varying pH? Thanks in advance.
the p-nitrophenyl phosphate disodium salt hexahydrate reagent can be used for both acid and alkaline phosphatase assay?
What is the difference between these assay?
Thank you all in advance
I am currently working on a school project and we are looking for a safe buffer to use to make a cardiac muscle tissue homogenate and to perform a Bradford assay.
We cannot use Imidazole buffer due to it being too toxic and we've already tried phosphate buffer, but I was wondering if there are any other substitute buffers we might be able to use.
I have isolated phosphate solubilizing bacteria (PSB) from soil using total plate count method with Pikovskayas Agar Media and incubated for 72 h at 30 degree Celsius. They have showed good Phosphate Solubilization Index (PSI) and robust growth. The obtained bacteria was cultivated in Nutrient Agar slant for 72 h at 30 degree Celsius and preserved at 4 degree Celsius for working culture. However, the PSB didn't show any growth in Luria Broth medium after I cultivated two loops from the slant. Can someone explain? Should the working culture preserved only in 30 degree Celsius?
Note: I have preserved the PSB culture in NA slants for almost a week.
I want to prepare a 0.05 M, pH 7 phosphate buffer solution that contain 1% w/v casein and 0.006 M EDTA for proteolytic activity determination. As I know, EDTA and casein only dissolve in a basic solution. My idea is to dissolve EDTA and casein in dibasic first, and then only put the monobasic solution. Is it correct? Can anyone suggest the correct, detail steps to prepare and maintain the concentration?
The statement of my reference is (I want to prepare it without cysteine): The extract (1.0 ml) was mixed with 1.0 ml of a reaction cocktail (contained 1% (w/v) of casein, 0.03 M cysteine, 0.006 M EDTA in 0.05 M phosphate, and a buffer pH 7.0).
Ketnawa, S., Chaiwut, P., & Rawdkuen, S. (2012). Pineapple wastes: A potential source for bromelain extraction. Food and Bioproducts Processing, 90(3), 385–391. https://doi.org/10.1016/j.fbp.2011.12.006
Your help is greatly appreciated and I thank you in advance.
What is the reliable and ideal medium (other than Sperber, NBRIP, and PVK media), which can be used for preliminary screening and isolation of potential Phosphorus Solubilizing Gram-positive bacteria?
Thanks a lot
the papers I read used phosphate buffer to make H2O2 stock solution and add it to the different conc. of tested compounds in the buffer. My compounds are insoluble in water, so if I make DMSO solvent to make a stock solution and add phosphate buffer(0.6ml of 40 mM H2O2) to it, the compounds would ppt.
It should matter which type of surfactant works best. Obviously some cationic types will do the job, but may have toxicity concerns. IS there a difference between sulphonates/sulphates and phosphonates/phosphates, between nonionic or anionic, is anything known on structure - 'killing' effectiveness of this virus?
In LAB fermentation medium, potassium phosphate dibasic is used as one of the nutrient component. However, pH is also adjusted at various levels. In this case, what is the use of potassium phosphate? Does it have any role other than buffering capacity? Will the concentration of phosphate in the media affect glucan production?
I was preparing a phosphate buffer and adjusting its pH to 7.2 from 9.0 by adding monobasic phosphate. In the beginning, it started to decrease fast but then, it went slowly (it was about pH=7.6). Even though I added too much monobasic solution, its pH was not increased easily. Then, it went to pH=7.3 easily but it stopped at pH=7.3 again. I wonder why it happened. I know it is related to its titration and the titration graph is fine to understand but I need a comprehensive explanation for it.
I did phosphorus adsorption with an initial concentration of 25 Pmg/L, by biochar dosage of 5 grams in 100 ml phosphate solution, finally, I get 8 Pmg/L, which is logically high but by the equation of Qe(mg/g)=(Co-Ce)*V/m, my adsorption data is very low compared to literature. Is there anyone who can help?
I am determining phosphate in well water, by the ascorbic acid method. After the addition of the combined reagents there is no color development. What could be the cause and how can it be remedied? could it be that the sample contain phosphates in very low concentrations that cannot be determined by this method?
I am doing an alpha-amylase assay and I am getting negative numbers for the inhibition as my sample concentration increases. I am using:
CNPG3 as substrate and trisodium phosphate pH 11 as stop solution of reaction.
Also, I have adjusted the control without inhibitor with 2.0 % DMSO, because my samples have this same solvent concentration.
I have got a great inhibition curve for acarbose.
I have an Ecoinvent data base. I am unable to find some chemicals or inventory. i.e. Corn Stover, Monopotassium Phosphate, Monosodium Phosphate, Octanol, Tri-n-Octylamine etc.
How can I find such inventory flow in database?
Thanks in advance!
I am trying to dissolve 1mg Betamethasone sodium phosphate in 1 ml of water but its not dissolving completely. Even i tried with methanol, methanol-water but its sparingly soluble in it and found to be less soluble than complete water and In dmso its not dissolving at all.
Kindly give some suggestion how to dissolve betamethasone.
Thanks in advance.
Detection of inorganic phosphate using Malachite green assay is usually associated with two crucial problems hampering colourimetric assays:
1) Precipitation of end product
2) Hydrolysis of substrates like ATP, GTP, UTP etc. releasing Pi, thus creating background noise. How best we can overcome those problems?
I would like to measure the activity of PP2A in neuroblastoma. So far I have tried many experiments and I am not able to get a very good activity. I am using the PP2A immunoprecipitation phosphatase assay kit from millipore. I have treated my cells with increasing concentrations of a PP2A activator for 24h. I extracted protein according to the kit protocol and used supernatants for enzyme assay. I get a slight increased activity with increasing concentrations and I am not satisfied because in the literature, they show better activity than mine. So does anyone has suggestion how to improve it?
1- How to improve the lysate preparation? maybe something during protein extraction already affects the enzyme activity. I handle my samples on ice.
2- in the untreated control, I have already a high level of free phosphate (400-600 pmoles of phosphate) and the gain of activiy in the treated samples is around 200-300 pmoles maximum, compared to the literature where they get at least 2-fold increase in activity compared to control.
3- is it always necessary to normalize the enzymatic assay with the IP?and if yes , how should I improve and make this IP? meaning how much should be loaded (same volume use for the enzymatic assay, knowing that if I use the supernatant for IP after elution, it is difficult to know exactly how much you have loaded?)
before the measurement of activity, the protein mixed with buffer, beads, enzyme are incubated at 4°C for 2h in the constant rotating motion instead of rocking motion as recommended by the kit instructions. Do you think it is enough time? also is 24h treatment to much for the treatment or to less? knowing that highest concentrations of the PP2A activator kill the cells within 24h? but still at lower range of dosage, the cells look OK
4-the protocole provided by milliopore does not describe any elution step, so I don´t measure the free phosphate in the supernatant rather I measure it in the bead fraction
5-sample storage: sually, I always perform the assay directly after protein isolation and calculation of concentrations, and I store thereafter the remaining samples at -80 °C. Is that OK?
Thank you all...
Hi, i am an undergraduate student and i'm trying to clone a gene fragment in a plasmid vector for the fist time for me. I have some questions, one of them is that i was reading that in some protocols gives the advice that if you want to insert a PCR product it most have be phosforilated before the ligation step, so you have to use a kinase to achieve that, but i also understand that restriction enzymes (at least some of them) leave a 5P end. So when i digest my PCR product it will be enough to leave 5P ends? Thanks in advance for your answers.
I prepared 1L, 1M phosphate buffer with pH6.0 and then autoclaved. I used 100ml from that stock and keep it for future use but after 2 weeks salts were deposited in the bottom of the bottle. Can anyone suggest why it is happening & how to avoid the deposition of salt in future?
I'll be using a polymer material as an adsorbent for both nitrogen and phosphate from synthetic wastewater (SW), my question is how will I be able to determine how much nitrogen or phosphate is removed or retained in the SW?
I've been trying to synthesize a chitosan(CS)/B-glycerol phosphate (B-GP) hydrogel that geliffies at 37oC without success, I only end with a really viscous solution after one week at 37oC. The chitosan (CS) I'm using has a molecular weight between 50 and 190 kDa and a deacetylation degree (DDA) of 75-85% I've read lots of papers. First I tried to reproduce the protocol of Preparation and Biodegradation of Thermosensitive Chitosan Hydrogel as a Function of pH and Temperature (Macromolecular Research, Vol. 12, No. 5, pp 507-511 (2004)). They use a CS with 161kDa and DDA=80% and prepare a 2% CS solution in 0,1M of HCl, and a 10% B-GP solution in water. Mix the solution and in 5 to 15min at 37oC they obtain a hydrogel.
=> I tried this but I couldn't get my CS dissolved in HCl 0,1M. Now I'm trying with the protocol of Effects of Chitosan Characteristics on the Physicochemical Properties, Antibacterial Activity, and Cytotoxicity of
Chitosan/2-Glycerophosphate/Nanosilver Hydrogels (doi:10.1002/app.37855) With a similar protocol but dissolving the CS in 0,1M fo HAc they obtain an hydrogel at 36oC with a CS of 161kDa and DDA=80%.
=> I do the same but I obtain a viscous solution. I've also read all of this papers: Characterization of thermosensitive chitosan gels for the sustained delivery of drugs (International Journal of Pharmaceutics 203 (2000) 89–98)
Novel injectable neutral solutions of chitosan form biodegradable gels in situ (Biomaterials 21 (2000) 2155-2161)
Rheological characterisation of thermogelling chitosan/glycerol-phosphate solutions (Carbohydrate Polymers 46 (2011) 39-47)
Physical Gelation of Chitosan in the Presence of B-Glycerophosphate: The Morphology and gelation of thermosensitive chitosan hydrogels (Biophysical Chemistry 117 (2005) 47 – 53)
Effect of Temperature (Biomacromolecules 2005, 6, 3267-3275)
Chitosan and glycerophosphate concentration dependence of solution behaviour and gel point using small amplitude oscillatory rheometry (Food Hydrocolloids 20 (2006) 936–945)
Glycerophosphate-based chitosan thermosensitive hydrogels and their biomedical applications (Carbohydrate Polymers 117 (2015) 524–536)
I would like to know if total phosphate (TP) and total nitrogen (TN) in soil can be determined with UV-Vis spectrophotometer or not. If somebody knows the method, I would like to get references.
I found one method to measure TP with NaOH fusion, but it need to use high temperature digestion and nickel crucible which we don't have. Therefore, I would like to know another possible method.
Thank you so much.
During Hplc analysis two peaks are inter mixed. Anyone tell me how I get separated, sharp peaks at suitable retention times respectively. The mobile is phosphate buffer pH-3 and acetonitrile (80:20). C18 column.
I am studying in disodium hydrogen phosphate salt hydrate and i have big problem for DSC analysis of this material.
in all DSC's reports the latent heat of fusion is lower than the amount contained in the reference.
I'm looking for suitable parameters for DSC analysis like rate of heat flow , start temperature , finish temperature , environment of test
or any parameters maybe important.
Released phosphorus (P) from fertilizers form initial reaction products after reaction with active cations present in soil, and P release rate and amount from those initial reaction products is very slow. Also, phosphatic fertilizer cost depend on its P release capacity from initial reaction products not on its nutrient content.