Methoxy PEG propionaldehyde is a stable aldehyde PEG that can be used for protein, antibody, peptides or carbohydrate N-terminal amine group pegylation reagent. The reaction between aldehyde group with the α-amine at the N-terminus produces an intermediate Schiff base. Further reduction with hydride will form a stable C-N bond. PEG aldehydes react with n-terminus amine groups at a pH of from 5.0 to 9.5. Higher pH will result in multiple Pegylation with both terminal and lysine groups.

Physical Properties:

• Off-white/white solid;
• Soluble in water, DMSO, DMF;
• Activity >90%; Peroxide<10ppm;

Storage Conditions:

• Store at -20 ⁰C

Reaction Procedures:

Generally, a 5- to 10-fold molar excess of PEG aldehyde over the amount of amine-containing material results in sufficient conjugation.

Materials Required:

• Pegylation buffer: Amine-free aqueous buffer, pH 5.0~6.5.
• PEG aldehyde stock solution: 50 mg in 1 mL conjugation buffer.
• Washing solution: Distilled water or any aqueous buffer.

Reaction Steps:

Dissolve targeted materials in pegylation buffer. Estimate the concentration of primary amine groups on the targeted materials. Add PEG aldehyde stock solution to the targeted conjugation materials with the final concentration keep at least 10 mg/mL. Allow mixture agitates at room temperature for 2~4 hrs at room temperature or overnight 4 ⁰C. After reaction, C=N bond can be reduced by sodium borohydride. Conjugate can be purified either by size exclusion chromatography or dialysis.