Patent ID: 7595198

Claim:
A method, comprising: a) providing: i) a diamine selected from the group consisting of 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7- diaminoheptane, 1,8-diaminooctane and 2,2′(Ethylenedioxy)diethylamine; and ii) a PC-Biotin-NHS selected from the group consisting of and b) reacting said diamine with said PC-Biotin-NHS under conditions such that a product is generated of the formula: Biotin-L-PR-AL wherein L is a first linker that is not labeled with stable isotopes; PR is a photocleavable group, and AL is a second linker comprising one or more —H 2 C—NH-groups.