The Monolith Protein Labeling Kit RED-MALEIMIDE 2nd Generation is optimized for labeling and purification of proteins with a molecular weight higher than 5 kDa. The dye carries a reactive maleimide group that reacts with cysteine residues to form a covalent bond. RED dyes are suited for Monolith NT.115 series and Monolith NT.Automated instruments with a RED detector (Nano and Pico). The kit contains material sufficient for 4 independent reactions.