Generally, a 10- to 20-fold molar excess of Maleimide PEG over the amount of thiol-containing material results in sufficient conjμgation.

Materials Required:

• Pegylation buffer, PBS buffer, pH 7 or other thiol-free buffer at pH 7.
• Maleimide stock solution: 100 mg in 1 mL conjμgation buffer.
• Washing solution: Distilled water or any aqueous buffer.

Reaction Steps:

Dissolve targeted materials in conjμgation buffer. Estimate the concentration thiol groups on the targeted materials. Add maleimide PEG stock solution to the targeted conjμgation materials with the final concentration keep at least 10 mg/mL. 10~50 molar excess of PEG maleimide needed for optimal conjμgation; Allow mixture agitates at room temperature for 2~4 hours at room temperature or overnight at 4 ⁰C.Conjμgate can be purified either by size exclusion chromatography or dialysis.