[Protein-analysis] Small peptide purification blues

[samreen shaikh]

SIR,

I AM A STUDENT WORKING ON PEPTIDE CHEMISTRY. I HAVE A PROTECTED AMINO ACID “ARGININE” THE REACTION DOES NOT GO TO COMPLETION AND HENCE THERE IS UNREACTED ARGININE ALONG WITH THE PROTECTED ARGININE. I HAVE TRIED SEPARATION BY CONVENTIONAL COLUMN CHROMATOGRAPHIC METHODS (ALUMINA)  BUT RECOVERED A MIXTURE OF PROTEDTED AND UNREACTED ARGININE. SOLVENT SYSTEM USED WAS METHANOL –DCM. THE SPOT OF THE PRODUCT DOES NOT MOVE ON THE TLC EVEN IN AMMONIATED METHANOL. COULD YOU ADVICE ME ON HOW TO PROCEED WITH THIS SEPARATION AND ISOLATION.

MY EMAIL ADDRESS IS samreen.shaikh from rediffmail.com. 

THANK YOU