GLUTARALDEHYDE CROSS-LINKING - FAST AND SLOW MODES

Intense activity in molecular cytochemistry has rekindled interest in questions regarding aldehyde chemistry in the fixation of biological specimens. The chemistry of glutaraldehyde crosslinking has been examined numerous times. The reaction of glutaraldehyde with common low molecular weight nucleophiles such as amino acids and sulfhydryl compounds, which are frequently encountered in biological systems, generates a wide range of products. The complexity of the condensation product mixture has thwarted a thorough understanding of crosslinking mechanisms. Despite this, it is useful to consider the condensation products of glutaraldehyde with itself and other low molecular weight precursors as the actual crosslinking structures. With that emphasis, this paper focuses on: 1) the molecular weight range of the condensation products as a function of available precursors, and 2) the kinetics of formation of the products.