Questions related to Surfactants
Does the increase of any surfactant such as texapon, lauryl alcohol ethoxylate 3 or 7 make a laundry detergent more opaque ? If yes is it a synergic effect or for example lauryl alcohol ethoxylate 3 do this itself?
Exact chemical structure means exact molar mass and not average molar mass of some kind mixture of homologs. So the Tween and Span series are not good.
I am working with protein extraction using porcine skin. prior to protein extraction I need to de-fat the tissue. I am using triton x to de-fat the tissue... how to determine if the defatting is completed?
Dispersing Tween 80 (TW 80) with an HLB of 15 in molten wax seems to form reverse micelles. If the molten wax formed with reverse micelles is put into water, will it become a normal micelle O/W structure? Compared to dispersing TW 80 in water first to make normal micelles and then adding molten wax, dispersing TW 80 in wax first and then putting it in water resulted in better dispersion. What is the principle?
I have thus far been unable to get DLS characterizations of some ultrasmall iron oxide nanoparticles that I purchased commercially and I believe it is due to high rates of aggregration, especially as I have had a hard time getting a the nanoparticles fully solubilizzed in solution (water, PBS, DMSO). I'm thinking that maybe adding a surfactant could be effective at reducing aggregation just for the purpose of hydrodynamic diameter and zetapotential readings. Any suggestions for best surfactant options?
i have formulate a nano-emulsion as a drug carrier ,consist of oil,surfactant and co surf. , upon mixing different ratios of oil,SA,CoSA the hydrodynamic measurment is about 20-30nm (average of three readings) but have occured three peaks first one is matched to hydrodynamic diameter(20-30nm) but the other two are large ? so,how to make it unimodal (one peak) and if it impossible , whta is the size of my particle ?
1. What exactly dictates the economic viability of a surfactant-aided chemical EOR - despite it's retention of surfactants through adsorption, precipitation, degradation & phase-trapping?
2. How exactly are we able to upscale - the observed physical/chemical processes associated with the ‘surfactant adsorption’ (van der Waals interactions between non-polar surfactant chains, hydrogen bonding, chemisorption, surface precipitation, electrostatic interaction, ion exchange, hydrophobic tail-solid interactions) from ‘sub-pore-scale’ to Darcy-scale?
Feasible to bridge the gap, if the cores are aged with crude oil in the presence of connate-water?
3. Feasible to quantify the magnitude of adsorbed surfactants as a function of formation brine-composition, reservoir rock-type and its mineralogical composition, pH & salinity of in-situ and injected fluid phases, surface-redox potential and the fundamental chemical structure of the injected surfactants?
4. What is the fraction of ‘total adsorbed surfactants’ that tend to get desorbed as a function of time (sorption kinetics)?
Does it depend on ‘surface wettability’ and ‘redox state’ of the used cores?
5. How do we ensure whether the rate at which surfactants get adsorbed remain the same - throughout the surfactant-aided chemical EOR treatment?
6. How about the desorption of surfactants?
Whether, do we have a correlation between surfactant adsorption and desorption rates?
7. Under what circumstances, are we supposed to expect
(a) non-equilibrium adsorption?;
(b) non-linear adsorption?; &
(c) sorption kinetics of the surfactants
associated with the surfactant-aided chemical EOR?
8. To what extent, are we able to restore a sandstone core from an oxidized- to a reduced-state towards replicating anaerobic reservoir conditions @ lab-scale in the absence of impacting core-mineralogy and pore-structure?
Feasible to quantify the reduction in surfactant adsorption in cores under anaerobic conditions - resulting from oxide removal and calcite dissolution?
9. Considering reservoir surface hydrophobicity as a function of time, how about the natural correlation between ‘the oil or water-wet surfaces of a sandstone/carbonate reservoir rock’ and ‘the adsorption of surfactants’?
10. How about the rate of wettability alterations for a sandstone and a carbonate reservoir?
11. How exactly the ‘specific surface area’ and the ‘adsorption density per unit surface area’ gets altered in a typical sandstone and carbonate reservoirs – resulting from wettability treatment of cores at the laboratory-scale – before and after reaching CMC?
12. Whether the observed ‘arrival time of surfactant front’ @ lab-scale would match with the field-scale scenario?
13. To what extent, the observed results on the surfactant concentration @ lab-scale reflect the real field scenario, particularly, following the surfactant breakthrough?
I have formulated a nanoemulsion formula consisting of oil, surfactant, and co-surfactant to be used as a carrier for a low-water-soluble drug in an oral formulation. However, I am unsure about which dilution would be best for characterizing and optimizing the droplet size. If I make a series of dilutions and measure the droplet size, which one should I select? What are the conditions for choosing the appropriate dilution? Thank you for your help.
Are there any methods for determination of tween 20 using CAD detector and acclaim surfactant column ? ( HPLC method)
I am using L-cysteine as a surfactant for the synthesis of nanoporous materials, but I couldn't find any information on the critical micelle concentrations (CMC) of L-cysteine.
In surface pressure vs. headgroup area isotherms are typically measured. How is it possible that in the condensed phase, the average surfactant area doesn't change but the surface pressure increases? Does the increased surface pressure mean more surfactant populate the interface, the headgroups are rearranging, or something else?
It appears that many surfactants will create rod-like micelles under various conditions but I can't seem to find a consensus as to how to smoothly control the shape of these micelles as well as their volume fraction.
In all of the literature I have read the shape of the micelles has been incidental to a larger question and I would love to see a systematic study if anyone knows of one!
Hello. Where can I find the equilibrium constants (unit of molarity^-1) of common surfactants like SDS, CTAB, Triton X-100 in water (specifically!) at room temperature?
Blank micelles formulation of surfactant X are transparent, however when preparing the correspondent drug-loaded micelles through solvent evaporation/nanoprecipitation method, the medium turns cloudy. Why?
As a doctoral candidate, I am currently investigating the solubility of my drug in various solvents, including oils, lipids, and surfactants. However, the practical laboratory approach is expensive and time-consuming. To overcome these limitations, I am interested in utilizing computational simulations to predict drug solubility in different solvents. Specifically, I am seeking guidance on the appropriate software and computational techniques that can be employed to accurately predict solubility. The ultimate goal is to validate the simulation results with experimental studies. Could you kindly recommend the most suitable software and computational techniques for this purpose?
Dear Professor/Professors I'm sorry to trouble, with this thing tha might be so easy, I thought I knew but somehow I confused myself
For instance, I have a 100 ml solution of CuO and DI water where my CuO is 0.1 wt% .
my total solution should be 100 ml and to that suspension I want to add a small percentage of surfactant lets say the ratio 1:0.5 in relation with the CuO
So to get the g from wt% of CuO I used the followed wt% formula
[weight percentage of CuO I want] = X (g of solute, this case CuO) / 100 (of total solution) *100
I derivate by X and got as result 0.1 g of CuO
for the surfactant I'm not really sure, lets say I want the ratio [1:0.5] respect to the CuO ,
I already know that I need 0.1 g of cooper so that I multiply for
0.1 * (0.5/100) and then I get how much grams of surfactant I should add to my solution
then for the total DI water ill just substract g of CuO and surfactant from 380
this is how i think it is please enlight me if i am wrong but the other doubt that i have is that i dont know how will it be, if I use lets say 360, 420 ml ? should i divide the ratio i want in that example 0.5 by 360?
thank you for your time to read until here, looking forward for an answer
Hi, I'm wondering what ways you use for improving the clearing of conjugate from nitrocellulose. my device has to use a large amount of gold conjugate and at the end, my NC is left with a noticeable faint purple color. I would like for my NC to be completely white at the end, any ideas?
I already used triton-x100, tween 20 and some other surfactants, but they don't do much.
Obviously blocking is an option but from experience i can say that the improvement is minimal and the work associated to it is not worth it.
This is a problem of background signal on the nitrocellulose but the test line is working fine, I just need to clear the excess conjugate from the surface. Any tips or tricks are appreciated, thank you
Hi, I am working on research based on biosurfactants. From last few months I feel my bacterial culture has lost its efficiency, there is a difference in growth pattern and isn't as slimy as it was before, the quantity of surfactant it produced has also changed. Any suggestions on how can it can be revived.
There is a big difference between natural intelligence and artificial intelligence. Natural intelligence is something we are born with and is based on our genetic makeup. Artificial intelligence is something that is created by humans and is based on algorithms and software.
1) What Is The Difference Between Artificial And Natural Intelligence – Surfactants
2) The Third Millennium AI-Driven Humanoid Robots-SwissCognitive
I am trying to make a macroemulsion system for eugenol oil using surfactant and solvent (Toluene), but actually it did not established yet. So, according to articles, I think it is better to use co-surfactant. Which co-surfactant do you recommend for Eugenol dissolving to water?
I was wondering to use 1-butanol , but I am not sure if it is helpful or not.
I am reviewing some literature for my thesis; I found in one article that NaCl salt drastically increases the CMC of carboxy betaine (Cocamidopropyl betaine). Is there any molecular-level explanation I should follow?
I know it is not true for ionic surfactants, but non-ionic and zwitterionic surfactants follow the 'salt-in' or 'salt-out' effect.
Many peptides and surfactant molecules produce nano-sized pore in giant unilameller vesicle (GUV). However, it is difficult to detect these pores. Is there any software to detect these pores?
At the moment I'm determining the cloud points of different non ionic surfactants. In the literature there are several methods described to measure the cloud point > 100°C. But I never found a description about cloud points below 0°C. If I would have a surfactants with an cloud point < 0°C, I could add an additive, like e.g. methanol to enlarge the value. After checking different concentrations of the additive, I could interpolate the cloud point.
I am trying to develop a LC/MS method for the analysis of 2 anionic surfactants. While the method seems to be working fine, I am facing an odd carryover issue.
- We are using a Xevo-TQS micro with an FTN autosampler.
- Mobile phase is 90/10/0.15 % ACN/H2O/FA with a flow of 0.2 ml/min, operated in negative mode, for 10 minutes. Peak elutes around 5 minutes.
- Needle wash is 80/20 ACN/H2O
- Tried 3 different columns and oddly, when we first start injections, we do not see carryover. But the following day, we see carryover in the blank injections. What could this mean?
- The area of the carryover does not drop with subsequent injections.
- If you inject a vial with just air in it (no solvent), the carryover disappears
Piroxicam ( zwitterionic forms) interact with two ionic surfactants SDS/CPB? possibility of interaction ?
Methylene blue ( cationic form) interact two ionic surfactants anionic and cationic surfactant? Possibility of interaction?
I investigated the cytotoxicity of several lipophilic compounds. I prepared the emulsion of Tween 80/PEG 600 (40/60 w/w) previously. When the lipophilic compound (once dissolved in DMSO) is emulsified in Tween80/PEG 600 and then diluted in the cell medium, no change in color of the cell medium was observed. The concentrations were: lipophilic compound 500 uM, DMSO 0.1%, Tween80 0.1% and PEG 600 0.15%.
To prepare the incubations with smaller concentrations, I first prepared the solvent, which I used for the dilution: DMSO alone was emulsified in Tween80/PEG 600 and then diluted in the cell medium. The concentrations remained the same. The color of the cell medium now changed (phenol red), indicating basic pH. Furthermore, the cytotoxicity assay showed that 50% of mortality is due to this solvent.
Can DMSO somehow disturb the emulsion and change pH? I can measure pH, but I need help finding out why adding only DMSO would change it.
Hello, I have been working on the synthesis of carbon dots (CDs) by electrochemical method, and I have been using monoethylene glycol as a surfactant agent, to avoid agglomeration of the CDs, however, agglomeration still occurs in the resulting solution, for this reason, I would like to know If anyone has any experience with any other type of surfactant or if someone could please guide me on what I may be missing to avoid agglomeration in the CDs.
In advance, many thanks to those who take the time to share their knowledge.
Dear college. Which surfactants are more appropriate for the synthesis of nanopolymers containing polar group such as amine group.
I seeks something more effective than oleic acid.
Ideally I would like something that is also non toxic in addition to being most effective*.
*: Able to keep particles separated and have a low rate of evaporation.
Can you give me some information about surfactant micellar structure size please?
(In my experiment, I used CTAB x NaSal for the drag reducing additive).
I would like to make a comparison the size of micellar structure size and Kolmogorov length scale.
Thank you very much.
I am standardizing a latex agglutination test for detecting WSSV with my specific antibody. But agglutination reaction is not evident. I am sure about my antibody; hence, I think it is not properly adhering to the surface of latex beads due to the presence of surfactant in the bead mix. Can anyone help?
I need to use sodium deoxycholate (NaDC) as surfactant in a methacrylate polymerization system for preparing hydrogel nanoparticles. But the reaction mixture (in water) precipitates before the formation of nanoparticles. In presence of SDS as surfactant, the reaction is carried out well.
Is there something important in working with sodium deoxycholate?
I read papers calculating based on weigh loss difference by TGA before and after surface modification. However, I found another paper (doi:10.1016/j.eurpolymj.2006.10.021) can calculate based on TGA only after surface modification. In this case they require few more values such as density and the radius of the nanoparticle.
[The equation is also given as the Image]
No of molecules per nm2 = [Weight loss * density of NP * radius of NP * 6.022^23] / [Molecular weight of surfactant (1-Weight loss) * 3*10^21]
Weight loss = 32.7 %
density of MNP = 5.1 g/ml
nanoparticle size (probably diameter)= 9 nm
Molecular weight of surfactant = 282.47 g/mol
The result they showed is 6.3 molcules per nm2
Is it true?
How to select surfactant for formulation of SLN and NLC theoretically.
1. Will it remain feasible to quantify the dispersion of the injected chemicals (Alkaline / Surfactant / Polymer) – in the absence of reproducing the ‘true fluid velocity field’ in a petroleum reservoir?
2. How exactly to correlate the findings of the laboratory-scale parameters such as IFT, contact-angle and wettability – which is associated with a size - which is much smaller than an individual pore-size, given the fact that the fictitious Darcy velocity remains to be viewed as the average of the true velocity over a reservoir porous volume - that is small relative to the reservoir length, width and thickness - but should remain larger relative to the individual pores (REV)?
3. Whether the concept of REV (Representative Elementary Volume) has ever been conceptualized clearly or verified experimentally in a real field-scale heterogeneous petroleum reservoir with multi-phase flow of fluids (oil-water and oil-water-gas)?
4. Will it remain feasible to quantify the ‘random molecular diffusion’ and ‘mechanical dispersion’ (resulting from the movement of the injected chemicals – below the REV scale - moving in a complex, tortuous paths leading to the additional mixing) of the injected chemicals associated with a chemical EOR (as against specifying a single value of ‘hydrodynamic dispersion coefficient’)?
5. Can we expect ‘Fickian dispersion’ of the injected chemicals – nearer to the injection well? If not, how to estimate the travel distance - required by the injected chemicals - before Fickian conditions occur?
6. How to deduce a ‘REV Dispersivity’ – given the vertical variation of horizontal permeabilities – for a finite reservoir thickness?
7. Feasible to deduce the ‘Reservoir Macro-Dispersivity’ – given the length of the reservoir? Even otherwise, will it remain meaningful, if we happen to apply the full reservoir macro-dispersion approach – nearer to the injection well – in chemical EOR applications?
8. Whether the ‘Macro-dispersion approach’ – ‘considering the permeability variations above the REV scale’ would remain feasible in a petroleum reservoir?
9. Whether the idea of scale-dependent macro-dispersion would remain as a conceptual artifact for describing multi-dimensional fluid flow in a petroleum reservoir?
I am preparing blend of chitosan and PHB but one polymer is hydrophilic and other is hydrophobic. Does the addition of surfactant like tween or PEG increase the miscibility of two polymers? Or do I need to graft functional groups or use solvent exchange method?
Dear Sir and Madam,
I have to green synthesize the CU Fe ZN and Ag nano particles from selected plant materials. To prevent the agglomeration of NPs, I want to add surfactant during the synthesis process.
What is a common surfactant that can be utilized in this synthesis, please?
Dear Sir and Madam,
I have read many research articles that synthesize NPs via green methods, but none of those procedures didn't mention the addition of surfactant. However,few of my experiments (green Cu, Zn NPs synthesis) have experienced the formation of sediments. I was curious whether it had agglomeration. Does anyone have a solution to this condition?
We are trying to quantify microplastics in effluent and are following ASTM D8333-20 to remove interfering organics in wastewater having medium to high suspended solids. The method suggests using reference spheres for QA/QC and adding them prior to the wet oxidation step. We added fluorescent polyethylene spheres (250-350 um) which tend to float on the surface. After adding the 30% hydrogen peroxide, placing the sample in the tube rocker for 60 minutes, and centrifuging for 3 minutes, the micropheres (250-300 um) were on the surface or mid-way in the supernatant, making it impossible not to remove some of them in the process of pipetting off the overlying liquid. Should we be adding a surfactant and , if so, how much? Are there suggestions for surrogates to mimic wastewater. We tried microcrystalline cellulose and soy bean meal.
I have read many articles. In some articles researchers first prepare the nanofluid using water then mix with fuel. And in some articles researchers directly put surfactant and nanoparticles in fuel and do the ulatrasonication. Please guide me for the correct method. By using water, fuel quality would not degrade?
After dispersion of both nanoparticles and surfactants with a particular concentration, there are some characterizations to be done for further experiment. So, one of those are viscosity and zeta potential. So can anyone please explain the result of these characterization for which we can do further experiment? What should be the results so that I will be assured for further experiments (I mean, suppose positive zeta potential means it will be good for stability or something else). So please explain these in detail. Thank you.
I tried to use this TAAB as surfactant however, i am not sure about the micelle formation during my reaction? If it forms micelle then what would be the micelle structure?
I would like to know how to break down protein crystal agglomerates. My crystallisation experiments yield quite a high number of crystal agglomerates (see images attached for 10x and 20x magnification). So far I am sonicating my sample for ~13 mins to break down crystal agglomerates but it does not seem to work (see attached image before_sonification for before and after comparison). I wonder whether you folks have any idea of how to separate the crystals to obtain images of single crystals (If you would suggest surfactants, which surfactants would you suggest?). I would need single/ individual crystals as I am developing a MATLAb® routine to derive the crystal size distribution from imaging crystals with an optical microscope.
With thanks and kindest regards,
I am a beginner in simulations.
I am trying to put some surfactants in a water/oil interface, fixing * and orienting the molecules at the interface with the hydrophilic head directed towards the water and the hydrophobic towards the oil.
Using Packmol I was able to create the box with water/surfactant / oil/surfactant/water, but I could not create a space between the water and the oil to place the surfactants and I could not even fix the molecules.
* I need to fix them so they do not interact with each other at the beginning of the simulation.
** I need this empty space to vary the number of molecules in the interface and then decrease the size of the box using NPT.
In the Packmol user guide, I saw in the examples that you have how to fix only one molecule:
fixed 0. 0. 0. 0. 0. 0.
end structure "
In this example, one molecule will be fixed with its center the origin and no rotation, but I do not know if I would have to fix several molecules at the same time.
I really appreciate it if you may help me.
Hi, I just did a surfactant self-assembly simulation. I found that the micelle size (the number of molecules in one cluster) is not always proportional to the concentration. Is that normal?
The micelle size produced by the 2% concentration solution is smaller than that produced by 3% but larger than that produced by 2.5%. I'm doing more simulations with various concentrations (1%, 1.5% ...), but before results are available, is there any relevant literature about that.
Any suggestions would be appreciated.
I have tired sonication and probe sonication in water and EtOH, however I am left with a cloudy suspension with visible grains at the bottom when shaken.
My procedure is measuring 10mg dry nanopowder in 5mL of solvent and sonication of between 30 mins and 1hr.
pipetting the cloudy solution onto a substrate and spincoating shows several grains visible under 50x microscope.
I am unsure if I need a surfactant or stabiliser to proceed or if my nanomaterials may have reaggregated in their container preventing nanodispersion?
Any input or advice is welcome, many thanks.
We fabricated the composite of PVA and nano-carbon-particles. The results of zeta sizer show that the size of PVA chains is increased and nano-carbon serves as a crosslinker. But in the case of rheometer's results, the viscosity of the above sample is decreased, which shows that nano-carbon serves as surfactant. The mechanical properties of composite structure are enhanced and XRD shows that the crystalline regions are less in the composite structure. What could be the possible reason of decrease in viscosity in your opinion ?
Here i have attached some XRD, zeta sizer and rheometer results..
I poured 3m 7500 with pico-surf into a closed chamber and heated it to 95 degrees and tried to make no bubbles inside the chamber
Can a stable emulsion of plant based essential oils with clean water be prepared without adding surfactants. How to quantify the oil in the emulsion.
Hello, I'm studying a surfactant called Benzalkonium chloride. I tested the toxicity study on this surfactant. ( BAC incubate with cells at different concentration) I want to know the mechanism behind it? How BAC breaks in to the cell membrane??
I want to optimize the synthesis of nanoparticles using DOE.
My system is: lipid A and lipid B (total mass of two lipids stays the same), surfactant and water.
Which DOE should I choose?
- Mixture - to make two lipids as a Mixture A and surfactant and water as a Mixture B?
- Combined - to make two lipids as a Mixture A and surfactant as a numeric factor (not mentioning water here)
Just to be clear. Total mass of lipids does not change, only the ratio. Then I want to check different masses of surfactant (w/w surfactant/total lipids mass). Water is added, so total mass of sample is constant.
I followed a literature to do SDS (sodium dodecyl sulfate) detection. In the method, it uses formamide mix with dye to create a detection working solution. However, the literature doesn't mention why use formamide to mix with surfactant like SDS? is it just act as an organic solvent?
I have seen in the papers that some additives added to polymers for producing foams?
Could you please explain what is the main function of these additives?
I'm doing research about how the concentration impacts the micelles' size by DLS(dynamic light scattering). the surfactant is a common sodium oleate, which has a CMC of 1.5 mg (300 g/mol)/10 mL. I have detected a various of concentrations including 15 mg/10 mL and 50 mg/ 10mL. The DLS results confused me, DLS data show a large micelle size peak around 423 nm, 319 nm, or 196 nm, respectively. The 50mg/10mL one has a peak around 2.55 nm which we considered as the actual micelle size peak, but why do all three systems show a large peak? (the solvent was treated by a 255 nm filter head)
I am preparing nanoparticles by solvent evaporation method where I am using Tween- 80 as surfactant. I am using ethyl cellulose as the polymer in acetone as organic phase and drug in 0.1 N HCl as aqueous phase. But the result of zeta potential is very poor. kindly suggest me how to minimize the particle agglomeration?
In more detail, i hope to observe micelle images in solutions of specific concentrations. However, no particles were found in the cryo-tem due to this particular concentration being low.
(solution concetration : 100uM, micelle size : 10nm)
I want to increase the concentration of the solution for image acquisition, but I know that the micelle formed by self-assembly of the surfactant changes whether or not the micelle is formed and the structure changes depending on the concentration of the surfactant.
So I don't want to change the concentration of the solution.
While investigating various materials, a method using dialysis was found1).
If dialysis is performed as shown in the figure below, it is thought that micelles can be concentrated inside the dialysis tube without changing the concentration of the entire solution. Is my thinking wrong?
1) Thompson, A. L., Ball, A. N., & Love, B. J. (2018). Controlled Release Characteristics of Aqueous PEO‐PPO‐PEO Micelles With Added Malachite Green, Erythrosin, and Cisplatin Determined by UV–Visible Spectroscopy. Journal of Surfactants and Detergents, 21(1), 5-15.
Briefly, the question is about the calculation of the molar ratios of Smix i.e. surfactant mixture and the oil phase ranging from 1:9 to 9:1 to get an optimized formulation.
1. the surfactant mixture (Smix) is composed of Surfactant (Labrasol) : Co-surfactant (PEG400) @ 1:2 molar ratio as a whole. This 1:2 Smix have to be emulsified with the oil phase as one entity ranging from 1:9 to 9:1.
2. My question is how should I calculate the molar ratios of Smix : Oil in moles and/or grams?
I'm currently conducting research on the dispersion and solubilization of organic pigments.
I am currently looking into surfactants, namely fatty alcohol ethoxylates, and was wondering if there are any good review papers on the ethoxylation degree and its effect on the surfactants.
Particularly the dispersing efficiency.