Aldehyde Reactive Linkers Bioconjugation: derivatives of hydrazine and oxyamine formed from carboxylate groups, can react specifically with aldehyde or ketone functional groups in target molecules. The reaction a hydrazone like linkage. This bond is relatively stable if it is formed with a ketone, but somewhat labile if the reaction is with an aldehyde group. However, the reaction rate of hydrazine derivatives with aldehydes is typically faster than the rate with ketones. Hydrazone formation with aldehydes, however, results in much more stable bonds than the easily reversible Schiff base interaction of an amine with an aldehyde.