Sulfo MBS (m-Maleimidobenzoyl-N-hydroxysulfosuccinimide Ester )

General description

MBS and its water-soluble analog Sulfo-MBS are heterobifunctional crosslinkers that contain N-hydroxysuccinimide (NHS) ester and maleimide groups, allowing for covalent conjugation of amine- and sulfhydryl-containing molecules. NHS esters react with primary amines at pH 7-9 to form amide bonds, while maleimides react with sulfhydryl groups at pH 6.5-7.5 to form stable thioether bonds. In aqueous solutions, hydrolytic degradation of the NHS ester is a competing reaction where the rate increases with increasing pH. The maleimide group is more stable than the NHS-ester group but will slowly hydrolyze and also lose its reaction specificity for sulfhydryls at pH values > 7.5. Hence, conjugation experiments employing these crosslinkers are usually performed at pH 7.2-7.5, with the NHS-ester (amine-targeted) reaction being accomplished before or simultaneously with the maleimide (sulfhydryl-targeted) reaction.

InChI Key:                         LKUULGDICDGFIQ-UHFFFAOYSA-M

Form:                                Powder

Molecular Weight:          416.3

Storage cond.:                 Desiccated

Solubility:                         Water soluble

Storage temp.:                −20°C

Features and Benefits:

• Reactive groups are Sulfo-NHS ester and maleimide
• Reactive towards amino and sulfhydryl groups
• Non-cleavable
• Water-soluble (compare to MBS)
• Membrane impermeable, allowing cell surface labeling