How much sodium azide crystal is need to preserve an antibody?

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When is it unnecessary to change organisational culture?

As a former management practitioner, I recall a generally accepted view that changing organisational culture is difficult, so you should only attempt it if the organisational change that you are...

27 February 2021 2,595 8 View

Can I use a protein-devoid condition as my negative control in ELISA?

Hello, I am running a sandwich-type ELISA where I am trying to inhibit a protein-protein interaction using small molecules. For each experiment, I determine my Z' (Z-prime) to determine the...

23 February 2021 7,429 1 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

What is the best temperature to coat an ELISA plate?

Hello, I want to control the temperature of my ELISA plate during incubations to get consistent results. In general, what is the best temperature to coat the plate with antibody? I have been...

16 February 2021 2,377 7 View

SPSS - Merging files by ID numbers that contain letters?

Hi, I'm trying to merge files from a data base of 20 files, each containing about 4000 subjects. Unfortunately the ID numbers are actually a combination of numbers and letters (e.g., b1458219)....

15 February 2021 5,833 3 View

How would I go about getting an expert review on the interview questions for the dissertation?

Good Evening, My name is David Marshall and I am Doctor of Management Student at Colorado Technical University Online. I just recently received approval from the IRB to start data collection on...

08 February 2021 346 7 View

How can I quantify the color of a solution?

I know colorimetry has been the standard way by way of measuring the concentration of a particular compound (solute) in a colored solution (solvent or measure quantities of a particular compound...

08 February 2021 2,673 1 View

ACE2 Blotted as a double band?

Hello, I have recently run a western of Vero cells for ACE2. I detected ACE2 at the correct size, but it presents as a double band. The sample was prepared by lysing cells in 1X Laemmli...

07 February 2021 6,973 3 View

SARS-CoV-2 Spike Protein Western Bands?

Hello, I am western blotting SARS-CoV-2 spike protein from lentiviral using an antibody against S1. To prepare samples, I mixed concentrated lentivirus 1:1 with 2X Laemmli buffer and boiled...

07 February 2021 3,643 4 View

How does DMSO percentage affect ELISA?

Hello, In my sandwich-type ELISA which is testing for small molecule inhibition of a protein-protein interaction, it seems that DMSO percentage and dilution protocol are important. I...

31 January 2021 6,771 1 View

Buffer to disrupt platelet alpha granules for PF4 quantification?

Hello! I want to quantify by ELISA the secreted (from platelets poor plasma) and the non-secreted (from platelet lysate) PF4 before and after TRAP stimulation. I will use the ELISA from R&D...

03 March 2021 1,499 2 View

Buffer Exchange using column packed with sephadex G-25 effect on protein concentration?

Hello, If i am doing a buffer exchange for an antibody of 1mg/mL, does the elution lose protein in the process of buffer exchange? For example, if i flow through 500 uL of 1mg/mL sample, and...

03 March 2021 6,299 3 View

How optimize the Size Exclusion Chromatography?

Hello! I'll do a size exclusion chromatography, but I only have an open column, and I'll perform the peptide extraction from yeast, using buffer lysis (sodium phosphate 50 mM/NaCl 30 mM/DNAse and...

01 March 2021 2,215 2 View

Why are my bands weird in this Agarose gel?

Can someone please give me some possible things that could go wrong? Here is my recipe: 0.5g Agarose 50 mL of TAE 1x 1 uL ethyl bromide. Gel was run at 100V for 1 hour. The buffer used is also TAE.

01 March 2021 9,952 3 View

What do I do with DLS peaks that are from the buffer?

I'm looking at the aggregation of my protein sample using DLS. Unfortunately, my buffer (20mM HEPES) also results in a set of peaks. These are at approximately 1 and 1000 d.nm. The lowest peak...

01 March 2021 9,015 2 View

Precipitate after adding laemmli buffer to protein solution containing Potassium Acetate?

Hi, I am running a size exclusion chromatography experiment with a buffer containing Potassium Acetate as a salt. I analyse these fractions through SDS-PAGE. After boiling my SEC fractions in...

01 March 2021 2,622 3 View

What is the most suitable resuspension buffer for TCA/acetone precipitated protein?

I need to extract protein from fermented carbon sources for Bradford assay. Most researchers experiencing insolubility of pellet in resuspension buffer. Please assist me to select most suitable...

26 February 2021 7,129 3 View

Will a 10xHis-tag prevent anti-MBP from binding to MBP?

I have a protein with a 10xHis-MBP tag on the N-terminus. I'm fairly certain I am expressing my protein, but I'm not getting a signal on my western blot. Is there a possibility that the 10xHis tag...

25 February 2021 8,404 3 View

What's the concentration recommend for recombinant protein use in western blotting?

I'm currently working having problem with the concentration for recombinant protein use in western blot, the one been used is Recombinant Human CD19 Fc Chimera Protein-rndsystem which does not...

24 February 2021 8,514 3 View

What urea buffer can i use for biotagged protein extraction from streptavidin beads?

Hi all, I have been doing research on biotagged LDB1 proteins in Mel cells. I purify the proteins using M280 streptavidin beads. The yield is very low so I've been trying to optimize it by...

24 February 2021 5,749 3 View