3-(N-Maleimidopropionyl)-biocytin

3-(N-Maleimidopropionyl)-biocytin (MPB) is a versatile thiol-specific biotinylating reagent. It is specific for sulfhydryl groups or reduced disulfide bonds and will not label proteins lacking a free sulfhydryl group at a pH between 6.5 and 7.5. This probe can be used in combination with the appropriate avidin- or streptavidin-conjugated markers (i.e., fluorescent, enzyme-conjugated, etc.). MPB can be used to detect protein sulfhydryl groups on dot blots with sensitivities in the femtomole range.{14917} MPB can be utilized for cell sorting, enzyme immunoassay, protein blotting, and various cytochemical procedures.{14917}