Study on Polyethylene Glycol Modification of RAGE Specific Antagonist Peptide

Aim We want to increase the biological stability of short peptides by PEG modification. Methods Through connecting the maleimide group to one end of polyethylene glycol and adding a cysteine (Cys) to one end of the short peptide, the short peptide was finally modified by PEG through chemical bonds. We established a reverse high-performance liquid chromatography (RP-HPLC) detection method to detect the change of substances 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 Changes in functional groups; tested the stability of RP-1 in rat plasma before and after modification. Result and discussion Through single factor test and orthogonal test, the pH in the reaction was 6, reaction temperature was 25 ?C, reaction time was 1H, and reaction ratio was PEG: RP-1C 1:1.5. The solution does not contain RP-1C after ultrafiltration. Peripheral plasma stability testing found that the modified short peptides greatly enhanced the stability. Conclusion Through experiments, we found the best conditions for the modification of short peptides, purification methods, and the stability of the modified short peptides was greatly improved.