Peptides synthetic, purification

Figure 23 Effect of temperature on RPC of a synthetic amphipathic a-helical peptide. Column Zorbax Rx-Cg (150 x 2.1 mm ID, S-pm particle size, 300-A pore size Hewlett-Packard, Little Falls Site, DE). Mobile phase, linear AB gradient, where eluent A is 0.05% aqueous trifluoroacetic acid (TFA), pH 2.0 and eluent B is 0.05% TFA in acetonitrile gradient rate, 2% acetonitrile/min flow rate, 0.25mL/min temperature, ambient (A), 50 C (B) or 70 C (C and D). Profile D is that of the peptide following purification at 70 C. The sequence of the peptide is shown in Table 1.

Hansen, P., Andersson, L., and Lindeberg, G., Purification of cysteine-containing synthetic peptides via the selective binding of the a-amino group to immobilised Cu2+ and Ni2+ ions, /. Chromatogr. A, 723, 51, 1996. 

Litowski, J. R., Semchuk, P. D., Mant, C. T., and Hodges, R. S., Hydrophilic interaction/cation-exchange chromatography for the purification of synthetic peptides from closely related impurities Serine side-chain acetylated peptides, /. Peptide Res., 54, 1, 1999. 

De Visser PC, van Helden M, Filippov DV, van der Marel GA, Drijfhout JW, van Boom JH, Noort D, Overkleeft HS (2003) A novel, Base-Labile Fluorous Amine Protecting Group Synthesis and Use as a Tag in the Purification of Synthetic Peptides. Tetrahedron Lett 44 9013-9016... 

J Rivier, R McClintock, R Galyean, H Anderson. Reversed-phase high-performance liquid chromatography preparative purification of synthetic peptides. J Chromatog 288, 303, 1984. 

AR Brown, SL Irving, R Ramage, G Raphy. (17-tetrabenzo[a,c,g,i]fluorenyl)methyl chloroformate (Tbfmoc-Cl) a reagent for the rapid and efficient purification of synthetic peptides and proteins. Tetrahedron Lett 51, 11815, 1995. 

Direct injection API-Electrospray MS is capable of analyzing much larger and less volatile substances than either EI/MS or CI/MS. As a result, this method is often used to provide structural information on peptides, proteins, and polymers derived from both natural and synthetic processes it is also useful in the analysis of many natural compounds including molecules such as saponins and flavonol glycosides, derived from plants. When using direct injection API-electrospray, partial purification and EC preparation are performed elsewhere and a collected fraction is dissolved in an appropriate solvent and injected as a bolus into the mass spectrometer (flow or direct injection or syringe infusion). This has an advantage, as the mass... 

A purification procedure for synthetic peptides was devised, 85 which uses the sulfo-benzoic anhydride reagent of Wieland et a 1.1X61 to terminate unreacted amino groups at each synthetic step and Sulfmoc chloride1 7 (1, Scheme 13) to derivatize the deprotected full-length peptide at the end of the synthesis. 

Following cleavage with hydrogen fluoride, the various classes of peptides were separated in a one-step purification procedure on a tertiary or quaternary amine column. After removal of the Sulfmoc group with 5% TEA, homogeneous Leu-Ala-Gly-Val, for example, was obtained. The Sulfmoc procedure was also very effective for purification of synthetic thymosin oq (28 residues). 87 This was the first use of an Fmoc derivative for selective and reversible orthogonal peptide purification. 

---