How can I keep the pH of urease reaction stable? Buffer? Ammonia removal?

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

Does different dilution factors affect negatively on NH3 reading ?

I have a sample of treated water sample & asked to obtain ammonia conc. in sample using a machine with 5-25 ppm detection range. However, upon testing with different dilution factors, all...

27 February 2021 8,483 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

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

Cloudy/high background western blot - can anyone help me?

Hi everyone! I try to detect VDR protein (~48 kDa) using Western Blot. After SDS-PAGE using 10% MP TGX Stain-Free Gel from BioRad I transferred the protein onto an metOH activated PVDF membrane...

23 February 2021 6,266 3 View

How to improve the buffer capacity of sea water?

Hello everyone I would like to improve the buffer capacity of seawater (pH ~8) in order to dissolve as much CO2 as possible without dropping the pH below 7.5 (a range between 7 - 7.5 is...

17 February 2021 2,797 2 View

Jasim Al-saadi

The best method to control pH is using buffer

Leonidas Emmanouilidis

Thanks Jasim!

I want to hydrolyse 500mM urea. I have used up to 100mM hepes or Tris buffer but in the end my pH is always around 9+.... increase further buffer concentration? Is it normal?

Achim Recktenwald

That's a lot of urea. From 0.5M urea you will be generating up to 1M ammonia.

Do you really need that much urea? No buffer will be able to keep your pH in check with that much base generated.

If you really need that much urea, then you may have to titrate the reaction back to normal pH range as you go with your reaction.

Yes I know its a lot of urea, but i cant make it less.

I was thinking to add some salt to precipitate the ammonia. Is this possible?

Majid Hazim Al Heidary

I have the same problem to Leonidas Emmanouilidis. I used urea fertilizer . my problems with ph over to 7.7. I am looking a method for reducing ph to 6.5 to increase leaves absorption.