Sterility - Science topic

In the preparation of the medium for IAA determination, is tryptophan added to the medium and sterilized or is it added after membrane filtration?

As soil already contained nitrogen. May I go with sterilize sand instead of soil and add hoagland solution containing different levels of N.

Hi everyone,

I am currently working on expressing a His-tagged protein of interest using a pHERD20T vector. I have successfully cloned my gene into the vector and am now attempting to electroporate Pseudomonas aeruginosa PAO1K with this construct. However, I am encountering difficulties in obtaining single colonies.

Here are the details of my experiment:

I prepared the antibiotic carbenicillin(200mg/ml) by dissolving the 2g of carbenicillin powder in sterile Milli-Q water, vortexing to dissolve completely and then adding milliQ to achieve a final volume of 10ml. This was followed by filter sterilizing the solution using a 0.22µm filter, aliquoting it and storing at -20°C. Therefore, I don't think I made any mistakes in preparing the antibiotic.

Despite trying different plasmid concentrations and volumes, I am unable to isolate single colonies. A colleague successfully performed electroporation with 100 ng of this plasmid in the past, so I am unsure if my plasmid concentration is too high or if there is another issue at play.

Has anyone experienced similar problems with this plasmid or have suggestions on how to improve transformation efficiency? Any insights or recommendations would be greatly appreciated.

Thank you!

I have a minimal medium where casein sodium salt needs to be added. As it's a medium to grow bacteria and to avoid contamination I have been trying to prepare a solution separately and filter sterilize it before adding to my media. The main problem is with 0,45 and 0,22 filters barely 2 mL can pass before the filter clogs up. anyone having the same experience? how do you filter sterilize it or do you just directly add the powder.

I have used antibacterial tablets in minimal concentration to grow fungal plates, still I find bacterial contaminations. I have also poured the culture media in sterilized Laminar airflow chamber. Does anyone have suggestions to control the contaminations.

I need to sterilize hydrogel (silk fibroin and tannic acid) in gel form, for cell experiment .i added 75% ethanol and use UV irradiation for sterilization but the hydrogel was broke due to low degradability. please suggest me appropriate method that can i follow it would be highly appreciate .

Hello everyone,

I’m working on microbial-based biofertilizers and need advice on sterilizing Polyvinylpyrrolidone (PVP) and Sodium Alginate while maintaining stability. Specifically, I am wondering:

Looking forward to your insights. Thanks! 😊

Hi all,

I’m optimizing my T cell stimulation protocol and have a basic but important question. I plan to stimulate T cells with anti-CD3/CD28 for 2 days, followed by restimulation with PMA/ionomycin and Brefeldin A for 4-5 hours, before staining for flow cytometry.

For my first experiment, I used a 96-well plate to culture the cells, but I’m considering incubating directly in FACS tubes from the start. My main reason is to maintain a high number of cells in each sample while avoiding additional transfer steps.

However, I have some concerns about sterility. While I can seal the tubes with parafilm during incubation, I’m unsure whether FACS tubes are sufficiently sterile for a 2-day incubation, given that they are exposed to air before adding cells.

Would it be advisable to incubate in FACS tubes for the full 2 days, or is it better to incubate in a well plate and transfer to FACS tubes later?

Any insights or experiences would be greatly appreciated!

Thanks in advance for your help!

We intend to export the product, 'Green Peas filled in glass jar with water' sterilized and packed to the US Market.

While filing a Scheduled process, LACF Office of FDA has asked for a Scientific reference which can serve as a 'Process Authority' that shows certain thermal processing parameters in the sterilizer at a minimum F0 value can help to achieve desired lethality to produce safe product to consumers.

Can someone help me to share any scientific publication for Green Peas or any other relevant vegetable sterilized in glass jar?

I have been a little concerned that the 7H9 media for growing mycobacteria becomes cloudy and crashes out of solution after autoclaving. It is fully dissolved before autoclaving and is clear, but once it has been autoclaved a sandy precipitate accumulates at the bottom of the bottle. Is this a standard problem? Is there anything we can do?

Good evening! I am a biotechnology student in Mexico and I am currently working in my thesis with drought induction in guava plants. The problem is my advisor don't know how to work with PEG. I was wondering I you could advise me about how to sterilize PEG. Also, does media solidifies with agar and PEG?

Thank you for your time!

Good evening I wonder if there is a solution to sterilize my plant hydrosol without altering the compounds.The first microbiological control test showed contamination likely originating from the glassware.

I am looking for data, protocol or guidelines recommending the use of sterile or non-sterile gloves during cystoscopy procedure.

Any feedback is most appreciated.

I need to isolate RNA from mouse adipose tissue using the GeneAid kit. There are some guidelines that mention using DEPC to remove RNAse. But DEPC stock is very difficult to find, are there any other reagents that can be used?

I want to use this substrate to determine cellulose enzyme on petri plates but I've read about low viscosity CMC that "long periods of heating CMC solutions at high temperatures (autoclaving) will degrade the product and permanently reduce viscosity. CMC is therefore very difficult to sterilize. γ-Irradiation, like heating, will degrade CMC. High viscosity CMC is more adversely affected by autoclaving and irradiation than is low viscosity CMC. Filtering CMC solutions tends to leave a gel behind because the material is fibrous, so solutions cannot be sterile filtered."

So, what is the most recommended CMC to determine this activity? Any CMC could be autoclaved? There are a lot of publications about this method with red Congo but nobody says how to sterilise CMC o wich viscosity grade they use.

Thanks beforehand.

Tatiana.

As i read articles the sequence of CpG ODN 685 (GNKG168) is ‘5-TCGTCGACGTCGTTCGTTCTC-3, but i couldn't really find information where is 6mer CpG motif and Phosphorothioate linkages? By its class its whole sequence should have these linkages. Are there any other details besides this that I should consider while ordering this oligonucleotide? I am reviewing one of the articles: "For example, to reconstitute 37 mg CpG ODN685 add 3.7 mL sterile saline". What concentration should i order so that it would be enough for 50 samples if I put 100μl?

I am trying to extract DNA from some tissue samples stored in 20% DMSO. I have already tried washing the samples with 3 washes with 1 ml of sterilized water left on for 5 minutes but got a very bad Nanodrop reading both in terms of quantity and quality of DNA. I am trying to figure out if the problem is the sample or the extraction protocol. Thanks for anyone who will help me.

What water should be used in a water jacketed CO2 incubator? The manual says to use "sterile distilled water", and when asking VWR by telephone, or looking at ThermoFisher online, they say it should be 50K - 1 M Ohm, and pH 7-9. We have a MilliQ machine for ultrapure water, nevertheless we ordered Poland Spring distilled water since the ultrapure is 18 M Ohm. However, I looked up the specs, and the Poland water is pH5. Calling VWR they didn't resolve it. They want the given parameters, and he worries about the effect of adding something like sodium bicarbonate.

Is everyone else simply not worrying about this? What do you use?

can centrifuging make salivary supernatant cell/microbe free (sterile)?

pls can somebody give a link to such a study that carried out microbial analysis of salivary supernatant.

We ordered primers for AQP4, AQP5, and ghrelin to assess their mRNA levels in the same tissue via RT-PCR. While AQP5 and ghrelin primers yielded consistent results, AQP4 has been problematic, consistently showing multiple peaks in the melting curve.

Details of our setup:

We have ensured all reagents were fresh. We're using fresh Master Mix and sterile water.

Could the issue stem from our AQP4 primers, and should we consider reordering them? Are there additional troubleshooting steps you would recommend?

Thanks in advance for your assistance.

Please Explain

how to differentiate between the retention time of all these degraded products using the HPLC analysis. the column being C18

If the percentage of medium of dilution of peptide (like sterile water) is 5% to 10 %. Will it affect Pseudomonas aeruginosa bacterial growth?

How can 30nm Fe3O4 nanoparticles be sterilized for use in biological experiments on cell culture? Can they be sterilized using ethanol, autoclave, or a hot air oven, or will these methods alter their structure and properties?

Hi everyone. I am doing transfections with mRNA and I want to avoid repeating freeze-thaw of mRNA solution. I would like to aliquot it but when I search, I cannot find suitable eppendorf tube which is both sterile and PCR-clean. Do you have any suggestions? Thank you in advance.

I'm currently studying the treatment of sewage wastewater and am interested in understanding the impact of autoclaving on the concentration of heavy metals. Specifically, I would like to know if the process of autoclaving (sterilizing using high-pressure steam) can reduce the levels of heavy metals present in the wastewater. Any insights, studies, or references to relevant research would be greatly appreciated.

Is it necessary to sterilize soil samples before preparing contaminated soil for experiments on degradation of organic pollutants in soil by PMS? A review of the large amount of papers shows that many people directly collect the soil after removing stones and leaves, dry and sieve it naturally, and then spray a certain concentration of organic solvent of the target pollutant without sterilizing it? Won't this have biodegradation implications?

Can anyone in pharmaceutical development help me with some questions ?

1) When developing in R&D a STERILE topical form (ointment, cream, gel) what should be the requirements for the cleanliness level and sterility ? Do you have to use a glovebox, or it's enough to use a laminar flow hood ?

2) Is it necessary to follow the GMP guidelines, and have clean room, or, since it's R&D, it's not necessary.

3) Sterility of the topical product must be proven on lab scale, or validated? It is self understood that on manufacturing scale, for commercial production, sterility is mandatory, and the validation batches have to be sterile, but are there any regulations in this sense for labs R&D?

#pharma #sterility #topical #cream #ointment

Hello, I am looking for a protocol to sterilize olive oil that will then be suitable to gavage to germ free mice. Importantly, if it were to be dry-heated, could it pose a fire risk?

I am Interested in detecting possible spores contamination in a non sterile product. what would be the best strategy to be followed.

I am trying to induce callus from woody plants grown in an arboretum. We have tried sterilizing explants using bleach but we are unable to get rid of funal contaminations.

The explants are woody stems. Are there better sterilization stategies we can adopt? Thanks for your help.

I used to prepare DMEM-powdered media for the cell culture use. The last step of media preparation is media filtration using 0.2um filters. Meanwhile, in case of 0.2um filters shortage, is it possible to alternatively prepare a sterile media for the cell culture without using 0.2um filters. Like to use 0.45um filters and then autoclave the media to ensure the sterile condition of the prepared media?

Hello,

I need your support and suggestions. When I autoclave broth media and put them in my anaerobic cabinet to pre-reduce, the pH will drop of 0.5-1.0 (depending on the medium composition and its buffering capacity) due to the CO2 present in the gas mix that is dissolving and acidifying the media. What I've been doing so far is autoclave, then adjust the pH (as autoclaving can alter the pH too) in sterile conditions, considering the pH drop after pre-reduction with the CO2-containing gas mix. However, adjusting the pH in sterile conditions is not optimal as I need to open the bottle and take aliquots with the risk of contaminating my media. So the ideal would be to correct the pH before autoclaving, but I will need to take into consideration pH alteration by the sterilization cycle and pre-reduction.

Does any of you have any suggestion or tips to address this point?

Thank you very much!

After formulation, can SBF be sterilized in the autoclaved without damaging the components? Or should it be sterile-filtered?

I performed RNA isolation using NucleoZOL reagent from rat brain tissue (it is very small piece appox. 2-3mg of tissue). As a control, I also did all the NucleoZOL procedure without a tissue in a sterile 1,5ml eppendorf tube. After that I measure RNA samples using nanodrop device. I got below results of first picture. Then, I measure all products that I use in Isolation procedure, such as NucleoZOL, isopropyl alcohol, ethyl alcohol, Rnase free water etc… and I got results on second picture. I could not figure it out. Is this normal and is there any contamination ? Lastly, what can I do with that?

I need this medium for cultivation of cervical epithelial cells. It is recommended to use EGF at a concentration of 0,01 ng/ml. In my vial I have 2,5 µg with a concentration of 0,0378 µg/µl (noted by manufacturer). This would mean for 0,01 ng/ml in 500 ml of medium I need to take 1,32 µl of the EGF vial. This seems very few. Especially because I read, that the medium - once supplemented - is stable only for two weeks.

How long do you use supplemented K-SFM?

Do you prepare less than 500 ml medium?

Do you sterile filter the BPE?

Do you have any other tipps?

Thank you very much in advance!

I’m trying to make a solution of metronidazole to add to drinking water of mice. I’m making a 100mg/mL solution but it won’t dilute. I need to filter sterilize the solution through a 0.2uM filter. I would love it if I can make it to 300mg/mL.

any suggestions?

I am conducting a research on comparing the effect of water floss to regular dental floss and I am wondering how can I sterilize my tips between participants.

I am planning to perform C13 MFA, and I was wondering how I can weigh the labeled glucose and add it to the media while maintaining sterility. I didn't find any protocol specifically explain this part.

when add glucose to MSM and sterilization in autoclave ,color of medium become red or brown.

hi, I recently worked with mycobacterium and saw a lot of paper that uses PBST to resuspend the mycobacterium pallet after centrifuge to prevent mycobacterium from clumping.

but tween 80 seems like cannot be autoclaved, Thus I want to ask that if I let PBST pass through a 0.22um filter, can it be called sterile PBST that can be used to resuspend my mycobacterium pellet?

Does 2-Mercaptoethanol degrade when autoclaved?

Hello

Does eukaryote DNA extraction need to perform in sterile condition with sterile (TE) buffer?

And what about plasmid extraction?

I read somewhere that plasmid DNA extraction does not need to be sterile as plasmid DNA is supercoiled and remains in solution when sodium acetate is added. This causes proteins and chromosomal DNA to precipitate and allows for the extraction of the purified plasmid DNA.

I have been trying to isolate good quality from mouse spleen for a while, but my RIN scores are always around 7 or below. My workflow typically includes harvesting the spleen in sterile pbs, sectioning it into 500um slices, staining overnight (rpmi and 1% bsa + antibody), imaging, dissociating in pbs, performing FACS (sterile method), collecting the pellet (centrifuging sorted sample), then lysing in trizol for rna extraction. I know that there are many steps that could be affecting the quality, but I always make sure to include an unprocessed control that is dissociated in trizol immediately after sectioning, and still the RIN is not satisfactory. There was one time I was able to obtain a RIN of 8.3, but I am wondering if there is anything specific I need to do to get reproducibly high RIN scores. I think my processing steps are not affecting the quality that much since the RIN scores of my unprocessed sample and processed samples are usually in the same range. Any advice would be valuable!

I have collagen solution that is in 0.02N acetic acid in 0.1mg/ml, I have autoclaving unit as my sterilization option.

Hello, I'm very new to cell culture, so I am trying to determine the best way to culture my cells.

I have been trying to culture salmon head kidney (SHK-1) since March and it is growing incredibly slowly and in "Islands" rather than evenly across the flask. I have only been able to passage it once in that time. There are various methods of how to grow it online, so any advice from someone who has successfully grown it would be appreciated.

Currently the cells are growing in L-15, 5% FBS, 1% Pen/Strep (in our cell culture lab we need to use antibiotics) supplemented with 4mM of glutamine. I have also added conditioned media.

I have seen that in some papers 2-Mercaptoethanol was added, does any one have any advice on how to add this to their media under sterile conditions? Our lab only has cell culture hoods which blow the air out towards you which is not ideal when using such a substance and our fume hoods will not be sterile for cell culture.

Thanks for taking the time to read this, any advice would be appreciated

Dear all,

Does know anyone how can I diagnose autoclavable lab devices? I do autoclave for some conical tubes with screw. Unfortunately, all tubes has been deformed regarding shape and color. I deem that they are resistant to 120 centigrade degree because the appearance shows very firm plastic.

Thanks in advance for your response

Best

I am trying to make 25ml aliquots of sterile spring water for some field work. I do not have access to a sterile hood, so I have been autoclaving spring water in 50ml PP/PPCO centrifuge tubes with aluminum foil tops and then sterilizing the caps separately in bleach before rinsing with alcohol and sterile water and capping. My intentions were to reduce exposure time to laboratory air to reduce chances of contamination through the transfer of water from glass bottle to the tubes.

After a few runs, only noticeable effects is sometimes salts precipitate out of the spring water and form a ring around the 50ml tube. I know literature indicates autoclaving plastics at 134C can release EA chemicals, but I have had trouble finding resources on 1) if this is safe to do and 2) if this actually reduces contamination risks.

I have been autoclaving for 30min at 120C on liquid cycle.

Any thoughts or comments are appreciated!

Since I opened a new frozen stock I am getting a lot of contamination. I have checked everything- medium, PBS, trypsin etc. Everything looks good.

What are the available guidlines for finished product visual inspection for sterile immunological veterinary products?

Storage and maintenance of pathogens is a costly and time-consuming affair, the recent study indicated that most of the pathogenic bacteria can be stored for several months at room temperature in sterile tap water without any hustle.

Ref DOI: 10.13140/RG.2.2.34672.84480

I want to check the cytotoxic effect of my hydrogels. Before conducting the experiment, in literature it has been reported that to wash the hydrogels with ethanol and then PBS thrice to remove the ethanol and then sterilize under UV for 1 or 2 h.

Does UV has any effect on the cross-linking of the hydrogels? Is it good practice to UV the samples before using them in the cell culturing experiment?

We our looking for feedback on our wound scratch assay. We are using HTR-8/SVneo cells.

This is our current protocol:

1. Create a wound in each well by scratching the confluent monolayer with a sterile 200 mL pipette tip.

2. Wash cells with PBS once to remove floating cells.

3. Add fresh serum-free media (1640RPMI ATCC mod.)

4. Image cells immediately after wounding, as well as at 6 h, 12h and 24 h after wounding.

Thank you in advance for your help!

Hi Researchers,

I am working on sulfur deficiency in arabidopsis plants and facing a strange issue that the Arabidopsis plants are not showing any deficiency symptoms even if I remove sulfate from the media. I am growing them in a modified MS salt (without sulfur) with 0.8% agar. I learned that agar may contain sulfate and therefore some researchers do remove them. However, if any of you have any real experience of removing sulfate from agar, could you let me know in detail.

My growth condition:

1. Surface sterilize and vernalize for 3d in 4"C

2. Germinate in full strenght MS media for 7d

3. Transfer to S-sufficient or S-deficient media and then study the effect.

I have tested the salts components and seems there are no problem with either media or seed stocks. If you have any other suggestions to obtain the desired response from Arabidopsis plants, please let me know.

Your help is much appreciated.

Best

Arijit

I'm interested in your previous experience with growing diatoms in plexiglass PBRs. I intend to use the photobioreactor for monospecific cultures/experiments with Skeletonema costatum. It has a diameter of approx. 150 mm, approx. 560 mm in height and a volume of 5 L.

I have a cell experiment and need to use a sterile round bottom W384-well plate, but most of them are labeled as non-pyrogenic instead of sterile. Does non-pyrogenic mean sterile? If not, what is the specific difference between them?

Dear everyone,

I am running a research project on fungal exosomes. Now, the exosome samples are being tested for sterility.

Can you suggest some methods/references based on the acceptable sterility test to meet regular QC guidelines that can confirm a bacterial contamination such as soil bacillus? If sterility is judged from assay as the 3M attest kit, can we say that it is an appropriate sterility standard that can be valid for FDA certification?

Your kind comments would be very much appreciated !

Best Regards,

Jeong-Hwan.

I'm doing disc diffusion experiments with E. coli TOP10 carrying my plasmid. I noticed that there was no difference between the TOP10 carrying the empty vector (my control) and TOP10 carrying my plasmid. But what is very strange is that neither ampicillin nor carbenicillin (solutions made fresh on the day) are killing TOP10 - which does NOT have ampicillin resistance.

My plasmid and the empty vector have kanamycin resistance. Originally I was including kanamycin (50ug/mL) in my LB agar plates. Then I lowered the kanamycin to 10ug/mL. Then I removed it entirely. This was in case there is some generic antibiotic resistance mechanism. Still the same result regardless of kanamycin inclusion.

I also have arabinose in my plates for the induction of the gene in my plasmid. But I do 0%, 0.002%, 0.02% and 0.2% and again this doesn't effect the result (although I have noticed that the lower the arabinose% the better growth I get - I tend to get lawns with 0% and 0.002% and single colonies for 0.02% and 0.2%.)

Antibiotic disc preparation: I'm using Oxoid blank antimicrobial susceptibility discs. I prepare a solution of 100mg/mL carbenicillin/ampicillin then do a few 10-fold dilutions to reach 1mg/mL. I filter-sterilise it then from this prepare solutions of 5, 10, 15,20 ug/mL. I then soak the discs (by dropping several discs into the solution tubes) for 30 mins minimum. I then remove them with sterile tweezers and lay them on sterile petri dishes by the blue flame to dry. Everything sterile.

I use the bacterial culture around OD600 0.5-0.7. I dilute it 1:1 then spread 200uL on plates with a sterile plastic L shape spreader. Immediately I place the now-dry discs onto the quadrant of the plates. I also have discs soaked in sterile water as controls. I then incubate them at 37oC for 20-24hrs.

Is the reason for not having zones of inhibition with carb or amp because the concentration is too low - do I need to go >20 ug/mL? Since the strain should be susceptible I would've thought that any concentration of carb/amp would inhibit growth. Alternatively, could my commercial chemically competent One Shot TOP10 have acquired resistance to amp/carb?

I won't have the results until tomorrow, but today I have tried the non-recombinant commercial TOP10 strain with discs of 5, 10, 15, 20, 100, 1000 ug/mL carbenicillin discs. I guess if it still isn't killing the TOP10 then it has somehow acquired amp resistance....?

Sorry this is not very concise but I wanted to include all the details .

I am trying to transform my plasmid into electrocompetent E. coli cells. They were prepared by washing the cells four times with sterile ice-cold water. After the pulsing, the time constant was shown to be 2.2ms which is far less than the expected time constant of ~5. What could be the reason for this happening? Do my cells need more washing?

Thanks.

It is a bile acid salt for microbial work.

to use warthons gel for culture we need to sterilize, what form of sterilization is most suitable as we aim to avoid contamination and on the other side avoid denaturation.

Hello, I prepared 4 mg/mL corticosterone in sesame oil for subcutaneous injection in mice. To do so, I had to sonicate and warm up the solution to facilitate corticosterone solubility. I was wondering if I could sterilize the solution before administration and how I can do that. I am worried I could cause infections at the injection site. I can't filter because sesame oil is very thick. I appreciate any feedback. Thanks

We do not have UV light inside our incubator. In such situations how to sterilize the insides of an incubator which was kept non functional for long?

I have gently scrubbed the inside with milli-Q water followed by 70% ethanol.

I intend to use 0.01% sodium azide to sterilize the inside.

Is this the way?

Thanks and Best

Please, how can I sterilize a nano preparation if it is affected by light, and it is in colloidal state and may lock the syringe filter? Later I have to study its effect on cultured cells.

Thanks in advance

I am using a sterilized GelMA to print structures using two-photon polymerization techniques. The printing procedure is carried out outside a sterilized (laminar flow hood, for example) environment, and I wondered how I could make the gels sterilized again after printing.

I would appreciate any insight or sharing of your experiences.

If a monoecious plant's tissue is exposed to chemical or radiation-induced mutations, is the male, or female part more likely to be rendered sterile?

Greetings! I want to know about glass petri dish..

I used plastic petri dish at baking step of microarray, but it was distorted... so I want to use glass dish. But, is it Okay I reuse that dishes? in dishes, only dH2O injected about 3~4ml.

Hi, I want to use plant preservative mixture (PPM) solution to sterilize my explants (from ex vitro culture) and I have some questions: is it recommend/not to use the PPM sterilization solution more than once, like I use it to sterilize my explants and then I store the remaining used solution in the refrigerator to use it again in the next day/week? How many times can I reuse the solution? And how long can I store the PPM sterilization solution? Should I make the solution fresh before doing the initiation? Thank You in advance

Hi, I want to sterilize the chitosan solution (for microbiological purposes). I don't want to autoclave the solution as it might affect the heat-sensitive additives in the solution. Also, I am not sure if I can use membrane filters as the viscosity of the solution is very high. Are there any suggestions?

Regards,

Elham

A company has claimed that by terminally sterilizing their medication, via autoclave, drug potency has improved. Does anyone have any information or articles they can refer me to on this?

I want to make an agar containing a certain concentration of sulfaguanidine. but:

The sulfaguanidine is not dissolved in room-temperature water. if dissolved in boiling water, it will separate out when the water temperature declines.

if sterilized it under 121℃，it will be destroyed and lost the ability of inhibiting bacteria growth.

so does someone meet this problem and how to solve it?

Exosomes can easily aggregate so we don't feel that a syringe filter will be a good choice.

Also, we can't use UV or heat as the exosomes will degrade.

So, what is the best method suggested in this case?

Hi, i wonder if i can sterillize guanidine thiocyanate 2M solution for qPCR purposes (to remove RNase and DNase), does anyone knows how the high temp impacts the solution? thanks

Hello,

I have band of my negative control. I am sure there is no contamination. I used new everything, sterile and change my gloves 5 times. I did negative control mix separately my samples. My PCR product should be 214 bp and my samples are not important, I know reason why there are two bands. What is negative control band? Really I don't know. It's look like picture there is no smear or something else.

I am afraid that I will kill the seeds by crutial concentration of EtOH and NACIO. May I get some good protocol or information?

Good evening,

How to avoid evaporation to drying in the wells of cell culture plates in a CO2 incubator (parameters shown in the attached photo)?

The medium evaporated and even some wells dried out in the middle of the plate while we put medium or sterile water in the border wells.

PS: we put a container with distilled water inside.

Could you help us to overcome this problem?

we would be very grateful, thank you.

I need to sterilize it in a way that doesn't alter the compound and can later be used for cell growth.

how to sterilize dextrose or glucose???

Hi,

I am going to do lipofectamine transfection of my plasmid with GOI into HEK 293 and ShSY5Y cell lines. However, I have a question at the colony picking stage. How can this be done, especially if I do not have a microscope like the EVOS inside my hood? Our microscope is big and outside the hood, but I will not be able to pick colonies outside of the BSC because of sterility issues. Has anyone found a workaround to this?

Thanks and Regards,

Mathangi

Hi all ,

I am performing root exudates collection for Arabidopsis using Hydroponics based system. However, I am unable to find any protocol where people have colleceted exudates in liquid MS media and performed LC-MS analysis based on that. Whereas most protocols say, they collect exudates in sterile MQ water. Can we perform root exudates analysis using the exudates collected in liquid MS in hydroponics system?

Appreciate any lead on this angle, thanks.