How to make ppb level concentration ?

Hi, I've N2 gas cylinder and 100 ppm NH3 gas cylinder. With these two cylinders, I'd like to make a ppb level (1- 100) concentration. Any idea how to do that?

01 February 2021 3,264 2 View

What is the proper aldosterone and CORT supplement in ADX mice?

Hi, I am struggling with the stress experiements in ADX mice. i tried 15ug/ml cort in the drinking water for ADX mice, however, the basal plasma cort are much higher than sham controls( 260ng/ml...

21 June 2020 386 1 View

What's the reason for the crossover of illuminated and dark JV curve in CIGS solar cells?

The distinct crossover anomalies are observed in my recent samples. It's explained in the book that there might be a barrier at the interface or in the absorber's near interface region.The barrier...

29 May 2020 675 4 View

How should I hydroxylate tungsten powder for organosilane grafting?

I am having trouble depositing MPTMS/APTES onto tungsten and I am concerned there are not enough hydroxyl groups on the powder surface. So far I have been exposing tungsten to water to hydroxylate...

04 February 2020 4,677 2 View

Could I extract RANK/RANKL/OPG mRNA from peripheral blood samples?

I want to know that whether it is possible to extract RANK/RANKL/OPG mRNA from peripheral blood samples instead of tissue homogenates. Thanks a lot.

07 September 2019 7,431 3 View

How to calculate the area of coverage hole of a disc tessellation?

The locations (centre coordinate x,y) and radii of all the circles are given. How to get the area of the coverage hole (area in green in the figure) ? Radii may not equal to each other. It is a...

11 June 2019 5,127 15 View

For WB, if there were DNA in my protein sample, how can I do?

Hi, everyone, I am working on transcriptional factor, I want to define what protein bind to my specific DNA, after I got the sample that bound to DNA, and use SDS buffer to boil it, I can find the...

24 June 2018 4,582 5 View

How the overall score is related to their subscale scores?

This is the third section of Items Decomposition: How to structure the Scores and Items. This section describes, using the graphical representation, how the score associated with all items in a...

07 June 2018 8,942 4 View

May I know who successfully knock-in target gene in mice? Using what methods?

Would appreciate if you can share how you done it. Thank you.

07 February 2018 2,091 1 View

EMSA-no binding band?

I am doing DNA-EMSA these days, when I try the control EBNA system, it is ok. But when I test my samples, there were no protein binding bands. In the first time, I use the volume suggested by the...

04 December 2017 5,658 6 View

Waters 2707 HPLC autosampler problem?

I am using a 2707 waters HPLC device. When I try to inject a sample, it says missing plate or rack. I changed the needle and calibrated its position but I still get the same problem. I even get...

02 March 2021 1,408 1 View

Should we change media after1st 6hrs after plating HUVEC bought from INVITROGEN?it's not recomended by invitrogen.Will DMSO present in stock matter?

We have HUVEC bought from Invitrogen. Cat no -C-003-5c. while first plating the cells we have bought the protocol suggests not to centrifuge the cell with media to remove the DMSO. Should we...

02 March 2021 3,713 2 View

How to normalise data on OPM package from R Studio ?

Good afternoon, I recently used OmniLog from BIOLOG for my experimentations : I tested the metabolism of different strains on 2 types of plates. I have 16 strains of 3 different groups...

02 March 2021 3,584 1 View

Benefits of the 24 welled plate?

We have always used the 96 welled plate, the 48 welled plate but apparently there is much evidence on the 24 welled plate and above all its benefits.It states it is the same you would use on ELISA...

28 February 2021 1,149 1 View

Can bacterial suspension be pipetted directly onto petri dish and agar poured onto it?

Hi, recently I encountered a protocol for plating which was not the usual method I have been practicing (pour LB agar onto plate, allow it to solidify, pipette bacterial suspension onto plate,...

28 February 2021 7,292 3 View

What is the best surface to culture cells isolated from a skin biopsy?

Hello, recently I am having some difficulties with maintaining the cell culture of primary cells isolated from a skin biopsy (normal and malignant). The coating of culture plates with Matrigel (a...

26 February 2021 6,151 2 View

Difficulty in cloning of 1kb gene into vector?

I am facing difficulties in cloning a 1kb gene into a vector (pJIT163). I have my gene on interest (GOI) in pUC57 and want to clone in pJIT163 using SalI and BamHI restriction sites. I am getting...

25 February 2021 3,221 7 View

Can cells be reused after using WST 8/ CCK 8 from Sigma Aldrich?

Hi all, Can cells be reused after I have seed them onto 96 well plates and test them with cell counting kit at OD450 (CCK8) at 12 hours, wash them with PBS x3 and add new media and let them...

24 February 2021 5,072 1 View

Standard curve shifting over time. How do I stabilise the ELISA?

24 February 2021 1,365 3 View

What is the standard protocol in doing replicates for C. elegans lifespan assay on solid media (thru worm picking)?

I would like to know what is the standard protocol in the number of worms per plate and number of plates per concentration of extract X in a lifespan assay done in solid media and not automated...

23 February 2021 9,933 1 View