Study on Polyethylene Glycol Modification of RAGE Specific Antagonist Peptide

ABSTRACT

Aim We want to increase the biological stability of short peptides by PEG modification. Methods Throughconnecting the maleimide group to one end of polyethylene glycol and adding a cysteine (Cys) to one end ofthe short peptide, the short peptide was finally modified by PEG through chemical bonds. We established areverse high-performance liquid chromatography (RP-HPLC) detection method to detect the change ofsubstances before and after the reaction; screened out the optimal detection method by orthogonal test;purified the modified short peptide by ultrafiltration; detected the reaction by infrared spectroscopy Changesin functional groups; tested the stability of RP-1 in rat plasma before and after modification. Result anddiscussion Through single factor test and orthogonal test, the pH in the reaction was 6, reaction temperaturewas 25 ˚C, reaction time was 1H, and reaction ratio was PEG RP-1C 11.5. The solution does not contain RP-1Cafter ultrafiltration. Peripheral plasma stability testing found that the modified short peptides greatlyenhanced the stability. Conclusion Through experiments, we found the best conditions for the modification ofshort peptides, purification methods, and the stability of the modified short peptides was greatly improved.