How do I make up a 0.01M Na2HP04/NaH2P04 solution?

How do I make up a 0.01M Na2HP04/NaH2P04 buffer solution, pH adjusted to 7? Both chemicals that I have on hand are anhydrous. The molecular weight of Na2HP04 is 141.96 g/mol and the molecular...

08 September 2019 191 4 View

How do I keep Salmonella alive in a dry sample such as fish meal?

We often find Salmonella in fish meal (dry sample with around 6 % moisture and 9 % fat) samples but after a while (a week or two) the levels drop so low that we cannot detect it anymore. Is there...

05 June 2019 5,733 4 View

Mueller Hinton Broth: Cation-adjusted or Not?

I would like to use Mueller Hinton Broth to test for Salmonella growth and also separately for E.coli (Testing Minimum Inhibitory Concentration). Would I use a cation adjusted broth for these two...

04 May 2018 7,991 3 View

How long should you autoclave 5 liters of liquid?

How long should you autoclave 5 liters of liquid such as Buffered Peptone Water or Saline? We use room temperature distilled water and work on 15 minutes at 121 degrees Celsius for 1 Liter...

02 March 2018 5,437 0 View

Can someone recommend a bio-assay system?

Can someone recommend a bio-assay system? I am looking to test a variety of liquid antimicrobial agents against bacteria and moulds.

02 March 2018 4,471 9 View

How would you test the efficacy of a dry antimicrobial product?

How would you test the efficacy of a dry antimicrobial product (powder form)?. The dry product is applied to dry samples. I am trying to see which dosage works the best so I have to test different...

01 February 2018 813 4 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