Description:

Maleimide PEG aldehyde is one of Nanocs premier thiol (-SH) and N-terminal amine group pegylation reagents. Maleimide group reacts with sulfhydryl (thiol) group at pH 6.5-7.5 rapidly and specifically while aldehyde group reacts with the α-amine at the N-terminus produces an intermediate Schiff base. Further reduction with hydride will form a stable C-N bond. Pegylated maleimide and aldehydes are water soluble and all reactions can be carried out in aqueous buffer. Aldehyde reacts 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:

• White/off-white solid;
• Soluble in warm water, DMSO, DMF;

Storage Conditions:

• Store at -20 ⁰C

Reaction Procedures:

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

Materials Required:

• Pegylation buffer: Amine and thiol free aqueous buffer, pH 5.0~6.5.
• Maleimide PEG aldehyde stock solution: 20 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 maleimide 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.