The Cryptate labeling kit is suitable for quick, easy labeling of peptides, proteins, and oligonucleotides with Europium cryptate. This kit is designed for very small-volume fast labeling needs, such as determining the best antibody among several antibodies available for HTRFassay development. The N-hydroxysuccinimide activated Europium-Trisbipyridine (TBP) supplied reacts with primary amines carried by the biomolecules to label, for simplified conjugation. The kit includes all the materials necessary for the labeling procedure (except dialysis and concentration devices).