Chromatography peptide synthesis

HPLC High Performance Liquid Chromatography LHRH Lutenizing Hormone Releasing Hormone PTC Phase transfer catalyst SPPS Solid Phase Peptide Synthesis TFA Trifluoro acetic acid... 

Aurora Biomolecules dedicates to peptide synthesis (and polyclonal antibody production) for any small quantity purpose. FMOC chemistry (on Perceptive Biosystems Pioneer instruments) is used for peptides synthesis Online monitoring of the coupling efficiencies and HATU activation helps insure that the major component of the synthesis is the correct oligopeptide. Purification is firstly carried out by size exclusion chromatography, and then by HPLC on a PE vision purification workstation. Typically, 20 mg of pure peptide are obtained. The molecular weight of the purified peptide is determined as a final confirmation of quality. 

E Bayer, W Rapp. Polystyrene-immobilized PEG chains. Dynamics and applications in peptide synthesis, immunology, and chromatography, in JM Harris, ed. Poly(Eth-ylene Glycol) Chemistry Biotechnical and Biomedical Applications. Plenum, New York, 1992, pp 326-345. 

ST Cheung, NL Benoiton. V-Methylamino acids in peptide synthesis. VI. A method for determining the enantiomeric purity of V-methylamino acids and their derivatives by ion-exchange chromatography as their C-terminal lysyl dipeptides. Can J Chem 55, 911, 1977. 

A. General description Eptifibatide is a cyclic heptapeptide containing six amino acids and one mercaptopropionyl residue. An interchain disulfide bridge is formed between the cysteine amide and the mercaptopropionyl moieties. Eptifibatide binds to the platelet receptor glycoprotein (gp) Ilb/IIIa of human platelets and inhibits platelet aggregation. The eptifibatide peptide is produced by solution-phase peptide synthesis, and is purified by preparative reverse-phase liquid chromatography and lyophifized. 

Although the racemization of the a-carbon can now be considered a potential problem, the synthesis of 32-peptides has been achieved in the same way as seen for 33-peptides. As the 32-amino acids cannot be prepared from the analogous a-amino acids, Seebach and co-workers 5,7 opted to use Evans oxazolidinone chemistry to produce enantiomerically pure 32-amino acids. Alkylation of 3-acyloxazolidin-2-ones 17 with A-(chloromethyl)benzamide yielded the products 18 with diastereomeric ratios between 93 7 and 99 1 (Scheme 8). Removal of the chiral auxiliary (Li0H/H202) and debenzoylation (refluxing acid) was followed by ion-exchange chromatography to yield the free 32-amino acids 20 which were converted by standard means into Boc 21 or benzyl ester 22 derivatives for peptide synthesis. 

Pessi et al. 68 prepared a different multiple antigen peptide employing the continuous-flow polypeptide procedure 69 for the solid-phase peptide synthesis. The resultant one-directional, octaantigen, polypeptide cascade 37 is depicted in Figure 4.2 and was characterized by gel permeation chromatography (GPC), FAB MS, and amino acid ratio analysis. 

Baru, M. B., Cherskii, V. V., Danilov, A. V., Moshnikov, S. A., and Mustaeva, L. G. (1995) Automatic SynChrom system for solid phase peptide synthesis and liquid column chromatography. 11. Application to solid phase peptide synthesis and liquid column chromatography. Russ. J. Bioorch. Chem. 21, 506—516. 

Classical peptide chemists were steeped in the tradition of organic chemistry in which intermediates are carefully analyzed and purified to homogeneity. Since the assembly of a desired peptide by solid-phase peptide synthesis occurs without purification of intermediates it is likely that truncated peptides and other impurities accumulate on the resin these are difficult to separate from the desired product. Prior to the 1970s, thin layer chromatography, paper chromatography, paper electrophoresis, and microchemical analysis were used to assess peptide homogeneity. None of these were sufficiently sensitive to distinguish the impurities that were expected from the solid-phase approach. 

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