How to make chemically-competent E.coli DH5-alpha cells?

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What is the smallest IRES capable for translation initiation?

Dear everyone, I work to improve the function of IRESes to make translation of mRNA and circRNA more efficient. The IRESes we are using are not very strong. I already looked at IRESite. If you...

15 February 2023 1,281 2 View

Thawing and feezing purified mRNA?

Dear colleagues, Could you please suggest the best way to thaw and freeze purified mRNA in water. I have batches of unencapsulated mRNA in nuclease-free water supernatant from nanoparticles and...

09 August 2022 3,269 3 View

What is the maximum nontoxic concentration of doxycycline for human iPSC cells?

Dear colleagues, I have applied 1 ug/mL of doxycyline to human iPSCs but most cells died within 24 hours after treatment. I was wondering if you have applied doxycyclin to iPSCs and know what...

26 January 2022 1,459 1 View

Reagents for histology slides?

Dear all, I am planning to study histology and want to do that at home. I have only stained a blood smear with Giemsa but now want to try a wider range of animal tissues. What reagents will I...

24 February 2021 5,919 3 View

What is the optimal propagation regime for pET-1M(KanR) and pMCSG7(AmpR) plasmids in DH5alpha E.coli?

Dear all, I am trying to harvest the low-expression plasmids in the mentioned E.coli strain. I constantly gel very low concentrations (30-50 ng/uL while the concentration is usually around 100...

08 February 2021 4,468 4 View

Does increasing antibiotic concentration also increase plasmid production in DH5a E.coli?

Dear all, I am propagating some plasmids with a human gene and an ampicillin resistance gene. My logic is that if ampicillin concentration will be increased, the concentration of plasmid (pSF)...

14 January 2021 992 3 View

Why didn't site-directed mutagenesis work?

Dear all, I was doing site-directed mutagenesis with one mutagenesis primer (fwd) and one normal primer (rev) to amplify a 6.5-kb plasmid. Then KLD was performed with dnp1 destroying the original...

10 January 2021 1,197 6 View

N3 buffer was in ice for some time - is it still fine to use it?

Good afternoon, I have stored P2 and N3 buffers in ice for about one hour. The P2 buffer turned milky and I discarded it. The N3 buffer didn't seem to have any chemical changes, so I am wondering...

24 December 2020 6,020 0 View

Electroporation of NK-92 cells?

Dear everyone, May you please recommend a protocol for electroporation of NK-92 cells using Neon machine? I have never done that before and woul dbe happy for recommendations if anyone had...

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What statistical test should I use?

Hi everyone, What statistical test would be most appropriate for this experiment? I want to compare two conditions against one another at different time points, e.g. mRNA1 vs mRNA2 at 24 hours,...

01 January 1970 3,102 5 View

Is there any way to quantify bacterial and fungal cells in their mixed culture?

I am working in fungal fermentation of soybean meal and there is bacterial growth in them at times. I am trying to quantify fungal cell counts and bacterial cells; but I haven't been able to do at...

07 August 2024 7,535 4 View

What precautions should be taken while handling S. aureus enterotoxin Type B in the lab?

I would like to understand potential safety concerns while handling SEB in the lab. Especially while working in animal house facility. Would like to know precautions for handling. Sigma MSDS...

07 August 2024 6,034 3 View

Why activated CAR-Jurkat cell could not kill targets?

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06 August 2024 641 2 View

How do soil microflora interact with plant roots and influence plant nutrition, health, and productivity?

06 August 2024 9,618 3 View

Research Methodology - Impact of Corporate Reputation on Stakeholders Behaviors?

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06 August 2024 949 0 View

How much total RNA concentration to be extracted from sorted plasma cells from bone marrow of C57BL/6 mice for RT-PCR ?

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Anyone having idea about VN primer for miRNA primer design ?

How to design VN primer to attach with universal reverse primer

05 August 2024 2,116 3 View

How to use Density Functional Theory to calculate carrier mobilities of solid system?

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04 August 2024 8,894 1 View

Does long-term culture of murine Monocytes result in macrophage differentiation?

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04 August 2024 7,282 2 View

Should I remove an item from a scale to raise Cronbach's alpha and McDonald's omega or is it better to leave it if they are both over .7 already?

Hello! I have this scale which had 10 items initially. I had to remove items 8 and 10 because they correlated negatively with the scale, and then I removed item 9 because Cronbach's alpha and...

01 August 2024 4,606 7 View

Igor Oscorbin

A classical protocol in Sambrook's book works well enough: http://cshprotocols.cshlp.org/content/2018/3/pdb.prot101188.full.pdf+html

Vikas Vitthal Andhale

https://ujemi.microbiology.ubc.ca/sites/default/files/Chang%20et%20al%20JEMI-methods%20Vol%201%20pg%2022-25.pdf

Maria Victorova

Dear all,

Thank you for the suggestions, will try them out.