MTSEA biotin selectively labels thiols under mild conditions. We offer MTSEA biotin with different linker lengths (Biotin-MTSEA, Biotin-X-MTSEA, and Biotin-XX-MTSEA), all of which allow selective labeling of cell surface thiols. Longer linkers should facilitate interaction between biotin and streptavidin.   MTSEA biotin-XX    MTSEA Biotincapcap; 2-((6-((6-((biotinoyl)amino)hexanoyl)amino)hexanoyl)amino)ethylmethanethiosulfonate  White solid soluble in DMF or DMSO  Store desiccated at -20°C  C25H45N5O6S3   MW: 607.7