Ethanol - Science topic

Which kind of HPLC column can be used for ethanol detection in LB medium after bacteria growth 24 hours?

Hi,

I've attempted to dissolve a plant extract in water, but it's not dissolve in water. I dissolved the extract in ethanol and then diluted it with water, but this time the dissolved extract precipitate. Could you suggest a method to prevent the extract from precipitating or to successfully dissolve it in water?

1. Which form of plant extracts shows the greatest potential for green synthesis of silver nanoparticle:

- direct homogenization with deionized water followed by filtration or centrifugation, or

- initial maceration with ethanol to form a semi-solid macerate later dissolved to a certain concentration with deionized water and filtered? Or can both methods yield effective results?

2. Should I dissolve the AgNO₃ and plant extract in deionized water, or can distilled water or even ethanol be used in the synthesis procedure?

I would greatly appreciate any insights or advice on these questions. Thank you in advance for your help.

I reacted 2,4 - dinitrophenyl hydrazine with salicylaldehyde to form a hydrazone using ethanol as solvent. Which solvent will be suitable for the recrystallization of the hydrazone since its no longer soluble in ethanol?

I will try to dry a 50% ethanol solution to obtain my dry extract. When I tried to have a 3rd party remove the solvent from my 20mL sample using purely the rotavap, they told me there was difficulty in drying it so I was thinking of only removing the ethanol such that I can safely lyophilize it. I was thinking of concentrating the sample to around 10% of its initial volume such that even if there's still some ethanol in it, I can simply dilute the extract with water to avoid any problems in the freeze dryer.

Hello all

I'm doing RNA seq, and using AMPure XP beads for cleanup steps and size selection of my RNA lib. Before using beads, my RNA concentration is good, however, after using Ampure beads the RNA concentration decreased too much. Most of my fragments had been washed away or were gone.

What should I do?

Before using Ampure beads, allow the beads to sit at room temp 30 minutes, and also, I used 80% ethanol for washing step.

I tried different volume ratio of beads to samples. From 1X tp 2X.

Thank you

Dear ResearchGate Community,

My research focuses on photocatalytic reduction of CO₂ to valuable liquid products like methanol, ethanol, formic acid. I need guidance and expertise in analysing these liquid products using Gas Chromatography with Flame Ionization Detection (GC-FID). Specifically, I am seeking assistance in optimizing the GC-FID method for accurate quantification and identification of various compounds produced through CO₂ photocatalysis. Any insights, protocols, or recommendations regarding sample preparation, column selection, detection parameters, and data interpretation would be greatly appreciated. Thank you in advance for your support.

Rahul Sinha

Please send me the link or DOI of the article.

Hi,

I have two samples containing 12-24% Ethanol (diluted by distilled water). I am wondering if these samples are frozen and then freeze dried, would that either decrease or get rid of the ethanol concentrations all together from sample?

Kind regards

I am planning to measure the ethanol and acetaldehyde contents in the leaves and crowns of turfgrass that were subjected to varying durations of ice encasement. Does anyone have a protocol for measuring these chemicals? If so, could you please share it with me?

hello,

can anyone help me with finding the solvent for iron ethoxide except ethanol and for iron isopropoxide except isopropanol.

I will be very thankful.

i am trying to stain different proteins of interest in human paraffinized section.

my signal should be the vessel only, but regardless of the antibody I get circle shaped spots , I tried antigen retrieval with trypsin, and I tried different dilution of antibodies (1:100-1:1000) and blocking in 5% and 10% donkey serum

why I have those spots? how can I reduce them? I have the same issue at different wave lengths (regardless of secondary antibodies tag)

this is my protocol:

•Thickness of sections : 10µ

•Deparaffinization by heat 55degrees for 20 min then (xylene - xylene: ethanol - ethanol) 10min each*twice

•Hydration (ethanol 95% - 70% - 50% - tab water) 5min each*twice

•Antigen retrieval : citrate buffer 10min microwave then leave in buffer to cool

•Peroxide treatment: 3%H2O2 10min at room temp

•Blocking: 5% Donkey serum + 0.3% Triton-PBS 1 hr RT

•Antibodies:

•Primary in 1%BSA: VWF (1:200)

•Secondary 1:500 of Rabbit 594

Initially, I conducted maceration with a 70% ethanol solvent for 3x24 hours to obtain the thick extract.

For the AgNP synthesis, the thick plant extract needs to be dissolved using deionized water as a solvent. However, upon dissolution, a significant amount of precipitate forms. I sonicated it for 20 minutes to aid dissolution, yet there was still precipitate present. Subsequently, I filtered it, resulting in a clear extract solution.

However, the resulting clear solution is unstable, even after storing it for only a day in the refrigerator, as precipitate forms again despite initially being a clear, filtered solution.

Are there any suggestions regarding storage or procedures for preparing the extract? Is it okay to filter the extract? Are there any suggestions regarding which filter paper to use?

*I do not use water as a solvent during maceration to ensure obtaining a thick extract so it will not be hard to determine the final extract concentration.

I would greatly appreciate any insights or advice on these questions. Thank you in advance for your help.

1) Sodium hydroxide + Chloroethane

2) Sodium ethoxide + Hydrogen

3) sNaCl

For example: the saturation molality of NaCl in pure water at 25°C is about 6.14 molal. The saturation molality of NaCl at 25°C, either in mixtures of water and formamide (the dielectric constant of formamide is much higher than that of water) or in mixtures of water and ethanol (the dielectric constant of ethanol is much lower than that of water) decreases in both cases.

I have not found any co-solvent that increases the solubility of NaCl compared to that of pure water. The same is true for all alkali halides!

I have used ethanolic hcl reagent (95% ethanol and 1.5N Hcl in 85:15 ratio) for sample extraction. I got OD value at the range of 0.031 to 0.068.

formula used :

Total Anthocyanin mg/100g) = ( OD x dilution x total volume made up x 100 )/ wt of sample x e

e : 98.2, absorbance of a solution containing 1 mg/ml anthocyanin.

But, resulted values are in low range. Please suggest me regarding this

Thank you

Since my compounds are soluble in ethanol, pure ethanol is showing a broad peak at 371 nm. Is it possible?

Hi. For gene deletion, I need huge quantities of highly concentrated linearized plasmid for electroporation, but, after restriction digest, I have hard time to recover satisfying quantities by ethanol or isopropanol precipitation (plasmid starting material used in restriction digest as well as linearized DNA recovered have been dosed using Qubit). Does anybody have some suggestions ?

I try to make Ga nanoparticle, using octadecene as solvent.

Solvent consist with octadecene, toluene, Ga nanoparticle and centrifuge the solution mixing with ethanol. what is the reason for centrifuge using ethanol?

Hi, I'm doing my first lab internship and I have a little problem, I fixed some fibroblasts with 70% cold ethanol and then I treated with gentian violet to study their morphology. Now I need to count the cells, but there are many of them. Is it possible to solubilize the violet and treat with DAPI? so I could count them faster in ImageJ

I am just curious to know what kind of chemical changes happen when ethanol comes in contact with materials made up of acrylic polymers, and how they crack.

Can I preserve FFPE tissue slices in ethanol at -80°C after dewaxing and then extract the metabolites the next day?

On many articles I found the following equation to measure porosity of hydrogels:

Percent porosity = (M2 - M1) / pV  × 100

Where M1 and M2 are the mass of the hydrogel before and after immersion in absolute ethanol, respectively; p is the density of absolute ethanol and V represents the volume of the hydrogel.

The problem is that after immersion in ethanol, the hydrogel sample (alginate-based) weights less. Additionally it has lost elasticity, becoming very fragile.

Any suggestion on why this happens and how I can measure the porosity differently?

We are planning to use ultrasonic-assisted extraction for sea urchins using ethanol as a solvent.

I want to get good films out of them, knowing that the melting process was complete, but the films weren't clear.

I need to do fluorescent microscopy using Propidium Iodide. I initially fixed my cells with 4% paraformaldehyde and saw red stain in Control cells. It turns out PFA is cell permeable. So if anyone has a protocol using Ethanol as a fixative please do share.

I have a spray pyrolysis machine capable of a substrate temperature of up to 500deg C. My theory is that I should be able to sonocate TiO2 nanopowder (already in Anatase crystal form) into ethanol, then add an rGO water dispersion dropwise to the TiO2 ethanol solution adjusting the pH with acetic acid to keep the TiO2 from precipitating in the presence of the water. I would then sonocate this mixture and stir for 24hrs, then spray to my pre-cleaned glass substrate using an ultrasonic spray head and substrate temperature of 110deg C to evaporate the solvents.

My objective would be to be left with a photocatalytic glass that can remove Methylene Blue from water under UVA light irradiation and be re-used over and over as the coating should be extremely stable.

Does anyone have anything to say to this? Issues? Better ways to use the equipment I have for the same outcome?

I see in the instructions and in some other manuals for poly-lysine coating that slides must be cleaned 'before attempting this procedure. Clean with acidic alcohol (i.e., 1% HCl in 70% ethanol) if necessary.' However, I don't have this HCl solution available and am wondering if I can simply wash them with regular dishwashing soap, and/or 75% ethanol, and/or acetone? My purpose is to use these slides for IHC of brain slices. Thank you!

I am trying to isolate DNA from clay soils from a rice paddy field. With the standard protocol of the Power soil kit, it doesn't work at all, probably because the clay sequest the DNA and it is eliminated with the humic ácids and others.

I've tried to use 1M Phosphate buffer/15% ethanol as I've read in one article, but it doesn't work so well for us. Is a solution that precipitate and it forms some crystals that may contain the DNA, so after all the protocol, the yields of DNA are low.

Has someone some experience with that? Thank you!

Hi here, I bought this product "https://avantilipids.com/product/840875" in powder form. My protocol for lipid nanoparticle synthesis uses a microfluidic system from PreciGenome. I need to dissolve the lipid in ethanol for nanoparticle synthesis. I tried ethanol and ethanol-chloroform-methanol (major-minor-minor portion); but it is not completely soluble. I would really appreciate it if you could please suggest a method to dissolve DOPA.

The process I use is the sol-gel method, which uses TBT added to 100ml ethanol and 0.4ml, 0.08mol/l KCL solution to prepare 900nm diameter titanium dioxide microspheres. After aging at 10 degrees Celsius for 20 hours, SEM characterization is performed. The morphology is as shown below shown：

I want to know how I can make TIO2 more monodisperse？

I’m testing antioxidants using DPPH. The extract is dissolved in 60% ethanol. I would like to know if DPPH is dissolved with absolute ethanol, the percentage of alcohol have an effect?

Can I use the extract dissolved in 60% ethanol or should the extract be precipitated before testing?

Thank you

I conducted a reaction involving substituted acetyl coumarin and substituted benzaldehyde in ethanol, with the addition of a catalytic amount of piperidine. The mixture was refluxed for 6 hours, filtered post-reflux, washed with cold ethanol, and recrystallized in ethanol. Please provide guidance on methods to achieve a higher yield.

I want to prepare a termite sample for SEM observation and i know it is dehydrated with a graded series of ethanol. but my sample has already been fixed in 75% ethanol for more than one month. So how to treat these samples to prepare for Scanning electron microscope? kindly suggest.

I tried to dissolve it in DMF, DMSO (individual and mixed), NMP, and ethanol but it is not dissolving completely in these solvents. All of these solvents make cloudy solution. Please help me to find the answer. Thank you in advance.

I have red poultry mite samples which have been stored in ethanol. Now I need to perform RNA and DNA extraction followed by shotgun metagenomic sequencing. I would like to know if there is a way to successfully extract the nucleic acids so that I have no inhibition or problems during the sequencing run. You opinion and experience is highly appreciated.

I need to lyophilize Fungi that Has been Ethanol Precipitated and dialyzed in water. I am having problems, because it unfreezes (after being frozen in liquid nitrogen) after I connected to the lyophilizer. The lyophilizer is set at 0.030 mBar and -38C. Is this temperature too high? Can anyone give me some ideas how to set the lyophilizer? Thank you

Numerous articles mention the combination of metal oxide, carbon black, and PTFE as a binder, followed by pressing onto an Al mesh. Yet, I encounter difficulties in achieving uniform pellets using this approach. What type of press is typically employed in such methods? Is the process as straightforward as mixing the three powders in a mortar and pressing afterward? Additionally, what pressure levels are recommended, and is the incorporation of water or ethanol necessary? I appreciate your assistance.

I have been having troubles with column purification (for DNA) recently. I am assuming that the reason is the residual ethanol. I used to centrifuge at max speed for 2 minutes to remove residual ethanol. Would using a desiccator do a better job at drying the column?

Hi!

I isolate RNA from Gram-positive bacteria using Trizol reagent (Invitrogen).

I would like to know why the centrifugation speed should be reduced from 12000 g to 7500 g during the ethanol wash step? Would anything happen to the sample if I used the same speed of 12000 g throughout the purification?

I am trying to undersatnd the bond formation and and functional group interaction at the biinding sites and a list of possible products that can be formed.

for example the binding of Palmitic acid and 1,8 cineole in ethanol at 60 degrees celsius

I came across a paper on the exposure of zebrafish to BPA at realistic environmental concentrations and I found no mention of any solvent used to dissolve the BPA. Instead, the exposure was carried out directly in water. Considering my experience with BPA, it’s commonly dissolved in DMSO or ethanol and isn’t easily soluble in water except at very low concentrations. Is there any literature demonstrating BPA exposure without the use of solvents?

Is it by using the inhibition (%) formula or simply plot a standard curve using absorbance and concentrations?

If using the inhibition (%) formula,

Is it correct if the negative control color is yellow-orange while with the increasing concentration the more intense the color of blue/purple? blank: ethanol. I used Trolox for standard

I synthesized Fe3O4 nanoparticles using the co-precipitation method. One of the procedure is reacting with NH4OH 25% until pH 11 and a black precipitate is formed. I want to wash the precipitates to pH 7 using distilled water and 96% ethanol. I am also using an external magnet. However, I tried washing it several times with distilled water and ethanol, the pH I got was only around 9-10 and couldn't reach pH 7. What should I do? Give me some advice

synthesized carbon dots by simple hydrothermal method, neither get dried by heating at 60 degree. its water dispersion not freezes at -30. how to dry them into powder. it is well dispersed in ethanol and methanol.

it was stored @ -20 degree.

The porosity of sponges was measured by the solvent method. The solvent was chosen as ethanol because of the insolubility of sponges in ethanol. A certain volume of the sponge

was cut accurately. The sample was dipped into ethanol and removed after saturation. The mass of the sample was measured before and after immersion in ethanol. The swelling degree (P) was calculated by the following formula

P=(m2-m1/vXp)X100

where m1 and m2 represent the weight of the sample before and after

immersion in ethanol, respectively. V and ρ represent the sample

volume and the density of ethanol (0.785 g/cm3).

I would like to ask if sample volume V is the volume of ethanol we take to immerse the sponge into it? Can somebody please clear my doubt?

Thank you.

Dear all,

has anybody some experience with using denatured ethanol in nucleic acid extraction (instead of molecular grade ethanol)? I cannot find any data/description about possible inhibitory effects of downstream PCR reactions. The denaturant could be any that is on the market (e.g. MEK/butanone).

I know pure Ethanol is of course the best solution, anyway I am curious and a bit surprised there are no (obvious) sources. I would be happy if you could share any hints/sources/experience you have!

BR,

Christian

Bunsen burner flames are used to create a "sterile field" to prevent contamination. Is there any evidence if, and to what extent, this actually works?

I've replicated a method I've found in a number of articles claiming to have produced a highly photocatalytic TiO2 thin coating but am not finding any success in degrading even low concentrations of Methylene Blue. Specifically, I'm adding TTIP (97% from Sigma Aldrich) dropwise under stirring at 500rpm and room temp into ethanol (bioethanol 99%). I have tried to reach the volume ratios described by others of 5mL TTIP to 50mL of Ethanol but find it quickly precipitates into large white particles and doesn't become transparent even after dropping the pH with HCl to 1.3. The maximum I could put in ending with a clear mostly sediment free solution is 1.3mL TTIP (into 50mL ethanol). From this transparent solution, I dip coated aluminium plates with a withdrawal speed of 1mm per second and calcined at 500°C for 1hr, then repeated the coating and calcining 6 times. I then put the aluminium plate in a quartz glass tube containing 50mL of Methylene Blue solution with an absorbance of 1.4 at 664nm and irradiated with an 11W UVA light under stirring. Spectrophotometer testing at 664nm showed no removal of Methylene Blue after a number of hours. Strangely, irradiating the solution with UVC 254nm light reduced the absorbance by 97% in 4 hours (just a reference check). I am out of funds but still have plenty of TTIP, HCl and ethanol as well as glacial Acetic Acid and ACAC (the last two chemicals not yet used). I also have Titanium Butoxide, HNO3 and 97% synthetic ethanol (in abundance). Does anyone have any suggestions of what I can do to make my coatings actually photocatalytic? What am I doing wrong? How can I maybe reach a molar ratio of 1:5 TTIP to Ethanol? Would this even help? Please help as I've run out of ideas.

Sample preparation with ethanol before vaccum arc melting

I am trying to make alumina nanofibers. so far i have prepared a solution of 0.6925 mol/kg

using Al(NO3)3.9H2O in water, ethanol and PVP.

I started with 12%PVP but the solution was not viscous enough, so i increased to 14% and still the same issue, i had dripping, no stable jet. I changed the ethanol to water ratios and the problem was still there in addition to the solution drying on the tip of the needle.

i am not getting anything to see on my collector except the dripping.

what would be the issue here ?

Ethanol is used as an solvent in my case.

I need a 200 ml volume even after the evaporation caused by the water-ethanol reaction?

I am working on bioethanol production from lignocellulosic biomass. However, I require some clarification on the methods for calculating initial sugar concentration, sugar consumption rate, ethanol yield (in g/g and g/l). Could you please recommend simple calculations or protocols?

how can i evaporate ethanol from extract without rotary evaporator?

I have been trying to pump 20% Ethanol and 30% KOH Aqueous Solution using silicon, Tygon etc tubing but all of these tend to dissolve in the Ethanol. Please suggest the tubings which could survive for long hours.

I would like to make an alumina dispersion in absolute ethanol, with a alumina content about 20 volume %. The viscosity and agglomeration of the dispersion must be as low as possible. The alumina powder is fine (about 200 nm in size) and pure (99,99 %). Literature on water dispersion is extensive but articles on ethanol based dispersions are rare. Water must be avoided. What kind of additive should I try?

Hello, I need to dissolve alpha tocopherol, I used DMSO and ethanol but it didn't have the effect I expected to take it to uv visible spectroscopy

if i dissolve the test material in ethanol 70%, and use the ethanol as negative control ? What do you think about this study design?

I want to dissolved my ethanol extract with ethanol to make different concentration for antibacterial test. Or is there another solvent that can be use for dissolving plant extract? And why is it better choice?

Upon linearization of plasmid DNA for electroporation mediated transformation in yeast, is it necessary to precipitate out the DNA from the restriction reaction via alcohol (With 75% ethanol). Isn't it possible to just deactivate the restriction enzyme via heat treatment and proceed towards transformation using the same restriction mixture?

I am releasing curcumin in a PBS/ethanol solution. The concentration of my drug is 5mg/ml in the encapsulation and I weighed 20mg of the loaded sample to perform the release studies. I take absorbance of the data at specific time intervals, after which I replace the same volume of PBS withdrawn. Volume withdrawn is 3ml out of a 10ml PBS/ethanol solution.

I can’t find the suitable conditions when I react hydrazide with aldehydes. I tried to stir in RT and at reflux for days. Also, I used different solvents, like; abs ethanol, glacial acetic acid, dry DMF, DCM. In addition to adding 1ml of glacial acetic acid or few drops of triethylamine as a catalyst. But, there’s no reaction and the start material (hydrazide) is the same "no consumption"

The old process uses boiling sulfuric acid as a catalyst to dehydrate ethanol to diethyl ether. I want to find a different set of catalysts that accomplish the conversion at high efficiency

Hi. In determination of total flavonoid in foods , AlCl3 10% is needed, my question is that it should be prepare whit ethanol solouthion or methanol?

I want to prepare a termite sample for SEM observation and i know it is dehydrated with a graded series of ethanol. but my sample has already been fixed in 75% ethanol for more than one month. So how to treat these samples to prepare for Scanning electron microscope? kindly suggest.

What are the steps in the regeneration of 'fresh' DEAE Sephacel, which comes in the swollen form, in 20% ethanol. And what is the significants of each chemicals in these steps, can anybody explain?

Dear ResearchGate Community

Which type of yeast does exist in this field?

Is there still a possibility of yeast contamination despite the continuous use of 70% ethanol and Bleach 10 % ?

What can be done if such contamination is observed?

Thank you in advance for your time and consideration.

Methanol and ethanol plant extracts of lemongrass, centella asiatica and moringa oleifera not showing activity in the varied concentration of lower to higher concentration 300mg/ml, 500mg/ml and 400mg/ml from the stock taing 50 100 150 and 200 microlitre) using disc and agar well diffusion method. tested organism is E.coli, Bacillus and staphylococcus aureus. Even after the review of literature of the related paper and following same methodology we not getting results please let me know where we lagging?

Thanks.

I have a question regarding MTT Assay. I got a I gram and I want to dilute it with ethanol instead of PBS. Should I use 20mg/ml dilution?

i want zeta potential diagram - or other solution for stabilization . Thanks

explain the protocol

Dear All

I study ethanol electrooxidation on Pd, which is supported on carbon using cyclic voltammetry.I prepare the working electrode by adding 5mg of powder to 33µL Nation and 467µL of ethanol followed by 20 min sonication.Then I add 20µL (200µg powder) of the ink into the glassy carbon electrode surface.Problem is some of the ink get dried on the ceramic outside surface of glassy carbon.I can not control or accuartely define how much of the slurry has dried on the glassy carbon and how much was dried on the ceramic surface.That is why I am obtaining non-reproducible CV results every electrode experiment I run.I use the same electrolyte concentration, scan rate, reference electrode, and same area of working electrode. The only different thing is the working electrode, which is from the same material ink. Theoretically, it should give identical or very similar CV results.

From literature it is seen that piperine is soluble in ethanol,methanol,and acetone but practically this is not happening. What can be the reason?

Plant DNA extraction methods

Hello

I want to purify indomethacin in ethanol but the problem is the formation of ester impurity due to esterification of acid part of indomethacin with ethanol. Is there any way to prevent estrification?

For washing of the DNA precipitate why do we only use 70% of ethanol ?? What happens if we use 100% or less concentration of Ethanol??