Product Description

CellMosaic’s Thiol Assay Kit with Purification is designed to assay the free thiol groups of a biopolymer after reducing or labeling with small molecule thiol-modification reagents. CellMosaic routinely uses this kit for its internal bioconjugation-related research. The product can be used together with antibody or other biopolymer labeling and conjugation kits to optimize loading.

Examples of these kits are antibody MMAE conjugation kits with VC-PAB linker (Cat#: CM11409, CM11409x3), antibody Mc-MMAF conjugation kits (CM11422 and CM11422x3), antibody MMAF conjugation kits with VC-PAB linker (CM11425 and CM11425x3), and F(ab’)2 MMAE conjugation kits (CM11416 and CM11416x3). Please follow the protocols for using the thiol assay kit along with these conjugation kits.

The assay is based on Ellman’s assay using 5’5’-dithio-bis-(2-nitrobenzoic acid) (DTNB) (Ellman, G.L. 1959, Tissue sulfhydryl groups. Arch Biochem Biophys. 82, 70–77). Thiol is reacted with DTNB to generate 2-nitro-5-thiobenzoic acid (TNB). TNB is orange in color and has an extinction coefficient of 14,150 M-1cm-1 at 412 nm (Riddles, P.W. Blakeley, R. L., and Zerner, B. 1983, Reassessment of Ellman’s reagent. Methods Enzymol. 91, 49-60). The amount of thiol groups will be calculated based on the amount of TNB generated.

Each package is sufficient for 10 purification and 5 assays (100 μL per assay volume).

Application of the product:

• Purification of a small amount of biopolymer after a reducing or thiol labeling reaction
• Assay the free thiol groups

Key Features of the product:

• Less than 30 minutes of preparation and assay time. Fast and easy to use.