Ɑ-Methoxy-ω-Pyridyldithio PEG

Orthopyridyl disulfide (OPSS) PEGs are thiol-specific PEGylation reagents that react with free sulfhydryls (-SH) at a wide pH range (pH 3-10) through disulfide exchange. The newly formed disulfide (S-S) bond is unstable in a reducing environment. Thus, the bond can be cleaved to reverse the pegylation and release free thiols.