The BSA Conjugation kit is one-step conjugation of a hapten to a carrier protein using the carboxylreactive carbodiimide as the crosslinker. The resulting conjugate is used for eliciting an immune response and antibody production against the hapten. The carboxyl-reactive carbodiimide reacts with exposed carboxyl and amino groups on peptides and proteins to form stable bonds. These kits contain BSA formulated in buffers compatible with the carboxylreactive carbodiimide reactions and desalt spin columns, which offer exceptional protein recovery by simple centrifugation step.