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

Buffer to disrupt platelet alpha granules for PF4 quantification?

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

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How optimize the Size Exclusion Chromatography?

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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?

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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...

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

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26 February 2021 7,129 3 View

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

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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

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.