Reference for 0.5 McFarland standard corresponding to 0.08 to 0.13?

Hi, I have a question about the 0.5 McFarland standard. In different websites I read that the for the 0.5 McFarland standard, the absorbance at a wavelength of 625 nm should be 0.08 to 0.13. I...

08 September 2018 4,826 1 View

How do I determine if specific points significantly deviate from the linear regression in a scatter plot?

Hi everyone, I would like to know how I can determine if a point significantly deviates from the linear regression when I plot the data in a scatter plot. I am using excel and I made a scatter...

06 July 2018 5,232 8 View

How to measure density with ImageJ in images that have different magnification?

Hi all, i am new in image processing and using ImageJ. I want to measure the density in areas of pictures that were originally taken at a different magnification. I attached an example that I hope...

05 June 2018 7,206 4 View

Theoretical question about western blot?

Hi, I am new with Western Blot and I need a few clarifications about the use of blocking and incubation solution. I understood that blocking is done to saturate the membrane with proteins...

11 December 2017 4,382 4 View

Preparation of sodium phosphate buffer?

Hi, I am preparing a sodium phosphate buffer solution at 0.1 M pH 7. For the preparation I am following this instruction that requires to mix 1 M Na2HPO4 and 1 M NaH2PO4 like this: 57.7 ml 1 M...

10 November 2017 6,517 3 View

How to calculate the enzyme activity from absorbance?

Hi, I have a question about how to calculate the enzyme activity from absorbance. I have absorbance values for different concentrations of my samples at different times. As far as I understood, I...

08 September 2017 1,623 4 View

Can you help me with understanding how to determine the beta lactamase activity?

08 September 2017 1,180 5 View

Which statistical test is most appropriate for my experiment?

08 September 2017 8,159 15 View

Cutting bands out of the agarose gel?

05 June 2017 3,063 1 View

Optimization of ligation?

05 June 2017 3,601 3 View

Can linear DNA be used as template for site-directed mutagenesis?

Is it possible to induce site-directed substitution mutation by quick-change method on linear dsDNA? or it has to be cloned in some vector? If yes, should it be treated with the Dpn1 enzyme...

03 March 2021 401 4 View

In PRIMER, is it possible to downweight certain taxa in multivariate community datasets to reflect uncertainty around identification??

I have a dataset with about 80 different species. As usual, some species are very easy to identify with certainty whereas others are more difficult, which means that I am less certain of my...

03 March 2021 8,066 4 View

PACYC PCR not working after several attempts. Would anyone have any suggestions?

So, I have been trying to run a pACYC PCR which will be used later on for a Gibson Assembly. However the PCR is not working. I have already tried gradient PCR and changing extension time; however...

02 March 2021 1,146 2 View

Does anyone have a recommendation for yeast reporter gene plasmid/protocol?

Hi, could anyone recommend a plasmid and/or protocol for reporter gene assay in S. cerevisiae? I want to assess the effect of growth conditions on a transcription factor, so I want to clone it`s...

01 March 2021 210 1 View

How to calculate the annealing temperature of a primer pair?

I have to amplify a gene and my primers just reached. The Tm for Forward primer is 64.2, and that of reverse primer is 65.5. Can some one suggest how to get the best annealing temperature? Thanks...

01 March 2021 360 7 View

Expression cloning by using cDNA,do I need to modify the cDNA first?

I am going to have a expression cloning of mammalian gene by using shuttle plasmid to transforming the E.coli However I don't know I should only inserting the Coding sequence ,or I can...

28 February 2021 5,440 3 View

Anybody with an idea on how do design specific primers for detecting tomato resistance genes tm-1, TM-2 and Tm2^2?

I am trying to identify these 3 genes among some tomato cultivar collections and after aligning some sequences from NCBI, I couldn't find unique sequences to target for specific primers. There...

28 February 2021 606 3 View

What is the ideal efficiency for a qPCR?

hello everyone, I need to do standard curves for my qPCR, what is the ideal efficiency range? I tried a primer (Mglu2 receptor) that gave an efficiency of 90.2%. Is it accepted?

28 February 2021 1,254 3 View

MiRNA qpcr problem?

Dear All, mirna primer showing some problem in the melting curve? any idea why? As attached is the melting curve. The forward sequence is obtained from miRBase and reverse primer is universal.

28 February 2021 5,008 4 View

Calculating volume of DNA required from DNA concentration?

Hi I am a bit confused. They are asking me to find out the volume of DNA required in ul (a total of 30-100 ng for genomic DNA) from the DNA concentration in the nanodrop reading which was 404.8...

26 February 2021 5,029 2 View