We supply six types of monomethoxy-NHS activated ester/carbonate-PEGs that differ in terms of the NHS carboxylate attachment chemistry. The reactivity order of these linkers in aqueous solution from lowest to highest is HS<GS<TS<PS<CS<AS. The stability order in neutral aqueous solution is reversed. After PEGylation, CS and GS types possessing ester groups are relatively susceptible to hydrolysis, whereas AS, PS, TS and HS types are resistant to hydrolysis because of their different chemical structures. Therefore, our customers can select the appropriate type according to their goals among the six types available.
Hydrolysis ratio of PEG-insulin (by using MeO-PEG-NHS type)
Hydrolysis test was conducted in pH 8 buffer solution at 4℃. Leaving insulin was measured by HPLC/UV.
※ HS type as well as AS type is stable (Hydr olysis test at 40℃)
Hydrolysis stability of activated ester and carbonate Linker
