What other reagent could be used as a positive control of the Griess method?

I use LPS at 5ug/mL as a positive control in the Griess method, but nitrite production is very low.

06 July 2019 4,009 4 View

I can use fluconazole for eliminating fungi in cultured cells?

09 October 2016 5,783 1 View

Why do my VERO cells die after a while?

VERO cells die after a while. There isn't evidence of contamination (bacteria and fungi). In addition, other cell lines aren't killed and with the same culture medium VERO. Which can be?

02 March 2015 8,189 7 View

The SGR amplification curve in my qPCR does not appear. However, when I put the SGR qPCR product in agarose gel the amplicon appears. What happened?

SGR is a sample and PJFH1 is endogenous control. *The mixture was the same for both samples, changing only the primers.

02 March 2015 4,370 10 View

Has anyone of you managed to express plaque forming units (PFU) to dengue virus in Vero E6 or LLCMK2 cells?

I can not express plaque forming units (PFU) to dengue virus.

08 September 2014 9,434 4 View

Does anyone use the reading of 495nm to assess cellular viability in Huh7.5 cells (MTT method)?

MTT method

05 June 2014 9,844 5 View

Does anyone know the base sequences of human endogenous primers for real time PCR? Such as BAC1, HPRT and GAPDH.

Companies sell with probe, but I don't need the probe. How to get the base sequences of the endogenous primer?

01 February 2014 5,667 3 View

How vaccines of covid 19 work?

Millions ask how vaccines of covid 19 be successful and safe, its here to explain generally how vaccine of pfizer work ,mRNA vaccines teach our cells how to make a protein that will trigger an...

28 February 2021 2,723 4 View

Problem with shRNA transfection. Why are only two plates getting contaminated instead of all?

I transfected my LNCaP-WT cells with 3 shRNA plus their NTC two weeks ago and split two puromycin selected cell plates on Friday last week(Feb 26). I checked for GFP in the cells, and they all...

28 February 2021 4,949 3 View

How long do vaccines protect us against COVID 19?

Or will we have to get vaccinated every year, as in the case of influenza?

27 February 2021 1,048 5 View

Best plasmid could be used as a standard curve for AAV titration?

I have been trying to have a good AAV titration for my production and I have tried different plasmids to set up as a standard curve but each one behaves differently. i am trying to use ITR for...

23 February 2021 5,167 3 View

How to control the variants vof covid 19 in second and third waves?

A the world find means to control covid 19 by vaccination ,new variants came to spread and make the world in fear and danger, to understand the conduct of these variants, es constantly change...

21 February 2021 3,080 6 View

Surprisingly low antibody titers against SASRS-COV-2 RBD in hamsters compared to mice?

21 February 2021 6,958 2 View

Will SARS-CoV-2 Spike be broken into S1 and S2 by denaturing conditions?

Hello, I am performing a western blot of my SARS-CoV-2 Spike-pseudotyped lentiviral particles. I denature my virus by adding concentrated virus to 2X Laemmli buffer at 1:1, then boiling for...

17 February 2021 4,844 4 View

How to calculate the TCID50 when the highest CPE is 50% or less?

I am doing TCID50 to measure progeny virus and some treatments protected the cells in a way that the highest CPE observed is 50% or less. How should I do the titre calculation in that case? Thank you!

16 February 2021 8,768 1 View

How to dissolve querceitin in HEPES?

I am trying to do the isothermal titration calorimetry study of quercetin. I want to reach a final concentration of 5 mM quercetin in HEPES or MES buffer with

15 February 2021 2,159 3 View

How to estimate/know plant virus concentration to make a standard curve in ELISA after serial dilution?

Hello, I am trying to know tomato virus titer/concentration in samples and I will perform serial dilution of the positive control. I wanted to ask How to estimate/know plant virus concentration to...

13 February 2021 6,534 4 View