Rajesh Kumar

12 Questions 6 Answers 0 Followers

Questions related from Rajesh Kumar

How to Improve Retention and Purification of a Hydrophilic Peptide on a C18 Prep Column?

Hi ResearchGate community, I’m encountering a problem purifying a highly hydrophilic peptide (2.5 kDa, ~10% hydrophobicity) using a preparative C18 column. Despite using a 0–30% (also tried:...

25 March 2025 2,050 8 View

How to do N-Terminal Mesylation of Synthetic Peptide?

Hi ResearchGate Community, I want to modify my synthetic peptide with N-terminal mesylation (i.e., the methanesulfonyl or mesyl group, Ms - CH3SO2) on a resin after final coupling. How can I...

05 February 2025 489 2 View

How to efficiently couple Indole-3-acetic Acid to Peptide N-terminus?

Dear ResearchGate community, I like to attach Indole-3-acetic acid (3-IAA) to the N-terminus of my peptide. Can I directly couple it using my Microwave Peptide Synthesizer (Liberty Blue, CEM), or...

07 November 2023 443 0 View

How to Analyze a Highly Hydrophobic Peptide on LC-MS System?

Dear ResearchGate Community, I am currently facing a challenge in the LC-MS analysis of a highly hydrophobic peptide (already purified to >98% by a manufacturer) on our 1260 LC-MS System. The...

15 October 2023 743 6 View

How to preserve the benzyloxycarbonyl (Cbz/Z) group at the N-terminus of the peptide during Peptide Cleavage?

I like to do SPPS by Fmoc/tBu chemistry to make a peptide (Z-Leu-Lys-Glu-Ala-OH) with an N-terminal-CBZ/Z group at Leu. I like to use Z- Leu-OH for the last coupling, but after the synthesis, I...

12 June 2023 330 1 View

How to synthesize N-Cbz-protected peptide by Fmoc/tBu-SPPS?

Dear Colleagues, How can I synthesize a peptide with N-terminal protection by the benzyloxycarbonyl group (Z-group) using Fmoc/tBu Solid-Phase Peptide Synthesis? Can Z-Leu-OH be coupled during...

09 June 2023 3,461 1 View

How to synthesize a peptide with 3 disulfide bridges?

Dear colleagues, Can we synthesize Alpha-Defensin-4 (Human; 33-mer) peptide with 3 disulfide bonds between Cys2-Cys30, Cys4-Cys19 and Cys9-Cys29 using the Microwave Liberty Blue peptide...

28 April 2023 594 0 View

How to remove MS noise spectra peaks in LC-MS?

Dear colleagues, I´ve one question regarding MS noise spectra in LC-MS. Actually, I am getting spectral (background noise?) peaks in both blank and water (-ve control) HPLC runs on Agilent´s...

05 January 2023 8,542 0 View

How to prevent aspartimide formation during Microwave-assisted peptide synthesis?

Dear researchgate community, Is there any good method/idea to prevent aspartimide formation during Microwave-assisted peptide synthesis (e.g., on CEM Liberty Blue)? My peptide (28-mer) has...

18 December 2022 7,528 3 View

How to induce mitochondrial damage in yeast?

Hi, Does anyone know how to induce mitochondrial damage in yeast (Saccharomyces cerevisiae) by either chemical or genetic approach? Thanks a lot Regards Rajesh

30 October 2019 1,299 4 View

Antibody for yeast mt-DNA encoded protein, COX2?

Does anybody know a good antibody for yeast mt-DNA encoded proteins? I could not find a company that makes such an antibody (e.g. COX1, COX2 and COX3). Thanks

17 March 2019 4,589 2 View

How to perform the BOC protection on indole-3-acetic acid?

Dear colleagues, I would like to do the BOC (tert-butyloxycarbonyl) protection on the indole ring of "Indole-3-acetic acid (3-IAA)" to get "N-Boc indole-3-acetic acid". Does anyone have an idea...

01 January 1970 2,165 0 View