How to determine amino acids or peptides bond present in a wastewater sample?

More Nimesha Shehani De Silva's questions See All

Is it possible to conduct biuret test to determine proteins for a wastewater sample?

My wastewater sample is reddish brown in color and is it possible to conduct biuret test for such kind of sample? If not what kind of test would be suitable?

02 March 2019 1,332 1 View

Why Do TDS and EC Increase with Larger Wastewater Volumes, While BOD and COD Decrease?

I have carried out MFC experiments on three different volumes, 50, 500 and 1000 mL of wastewater. Results after MFC treatment shows that TDS and EC are more in larger volumes of water i.e. TDS and...

09 August 2024 9,621 0 View

How to increase simulation box size?

We intend to study the interaction between peptides and polymer (like PP, PE and PS) through MD simulations using Martini force fields ( Martini 2 for PP and Martini 3 for PE, PS). We have...

08 August 2024 4,842 0 View

Separation of organic acids-HPLC?

Hello What should be done to separate and identify organic acids in HPC when their RetTime is the same?Like oxalic acid with Propanoic Acid.or acids that have a very close RetTime.

07 August 2024 8,782 3 View

Unusual intensity drop in some sections of chromatograms in DDA?

Hi, we have measured tryptic peptides using both DDA and DIA method on QExactive. In DDA replicates i saw unusual intensity drops occurring at the same sections of chromatograms in DDA replicates...

07 August 2024 3,218 4 View

Determining the worth of a point improvement in Hamilton Depression Scale?

Dear readers, Thanks for your attention. I am wondering about the health economic problem of quantifying the value of interventions which a) prevent, b) improve symptom profile and c) ultimately...

05 August 2024 3,246 1 View

Could dyes amplify the spectrum of light to a specific wavelength?

I am interested to know the behavior of dyes toward light. Specifically, Blue dyes re-emit the spectrum, especially from the green zone (known as principal in LED lamps, and blue dyes are known...

05 August 2024 3,290 1 View

How to analyze multiple phosphorilation sites?

Hello, I am currently analyzing some phosphoproteomics data, but I have peptides with multiple phosphorylation sites or phosphorylations together with carbamidomethylation or oxidation. How can I...

04 August 2024 8,432 3 View

Recovery rate after peptide desalting using Sep-pack C18 1 cc Vac Cartridge?

Recently I'm trying to use Sep-pack C18 1 cc Vac Cartridge (Waters: SKU: WAT054955) to desalt digested peptides. However, the recovery rate is usually 40-60%. What is the normal recovery rate?

31 July 2024 6,544 11 View

Conjugation of PEG-Amine to an Amino Acid Using EDC?

I am attempting to conjugate PEG to an amino acid at the C-terminus, for the purposes of producing nanoparticles. I have been told that PEG modified with amine groups can be used for this purpose,...

31 July 2024 2,033 1 View

Is it possible to use a safer acid instead of monochloroacetic acid to convert bacterial cellulose to carboxymethyl cellulose?

Hi, researchers, Is it possible to use a safer acid instead of monochloroacetic acid to convert bacterial cellulose to carboxymethyl cellulose?

29 July 2024 4,570 0 View

Markus Christ

Hi Nimesha,

have you ever heard of the Biuret test?

https://en.wikipedia.org/wiki/Biuret_test

Regards

Markus

Rafea Naffa

There are several methods for amino acid analysis including OPA and AQC reagents for derivatisation and separation on C18 using water and acetonitrile solvents and fluorescence detection.

Christoph Wittmann

Dear Nimesha,

separate the solids from the supernatant to go for free amino acids, using centrifugation and filtration and go for HPLC analysis (which is very routine in most labs). Check e.g. prvious literature:

Article Anaerobic degradation of amino acids generated from the hydr...

Best,

Christoph