Glutaraldehyde possesses unique characteristics that render it one of the most effective protein crosslinking reagents. It can be present in at least 13 different forms depending on solution conditions such as pH, concentration, temperature, etc. Substantial literature is found concerning the use of glutaraldehyde for protein immobilization, yet there is no agreement about the main reactive species that participates in the crosslinking process because monomeric and polymeric forms are in equilibrium. Glutaraldehyde may react with proteins by several means such as aldol condensation or Michael-type addition, and we show here 8 different reactions for various aqueous forms of this reagent. As a result of these discrepancies and the unique characteristics of each enzyme, crosslinking procedures using glutaraldehyde are largely developed through empirical observation. The choice of the enzyme-glutaraldehyde ratio, as well as their final concentration, is critical because insolubilization of the enzyme must result in minimal distortion of its structure in order to retain catalytic activity. The purpose of this paper is to give an overview of glutaraldehyde as a crosslinking reagent by describing its structure and chemical properties in aqueous solution in an attempt to explain its high reactivity toward proteins, particularly as applied to the production of insoluble enzymes.

https://www.future-science.com/doi/pdf/10.2144/04375RV01

Glutaraldehyde: behavior in aqueous solution, reaction with proteins, and application to enzyme crosslinking.

Glutaraldehyde as a fixative in bioprostheses and drug delivery matrices.

Bacterial spores are among the most resistant of all living cells to biocides, although the response depends on the stage of sporulation. The development of resistance to some agents such as chlorhexidine occurs much earlier in sporulation than does resistance to glutaraldehyde, which is a very late event. During germination or outgrowth or both, resistance is lost and the cells become as susceptible to biocides as nonsporulating bacteria. Mechanisms of spore resistance to, and the action of, biocides are discussed, and possible means of enhancing antispore activity are considered. The clinical and other uses of sporicidal and sporostatic chemical agents are described.

Bacterial spores and chemical sporicidal agents.

Immobilization of proteins to solid matrices has been performed for the last thirty years and has provided numerous examples of successful preparations with use in enzyme reactors, sensor preparation and immunodiagnostics. Among the arsenal of coupling reagents and procedures, glutaraldehyde plays a critical role due to its reliability and ease of use. It displays a complex chemistry that is transparent to most practitioners of immobilization. In this article we detail the structure and reactivity of glutaraldehyde protein immobilization.

The chemistry of enzyme and protein immobilization with glutaraldehyde

https://www.onlinelibrary.wiley.com/doi/pdf/10.1111/j.1365-2672.1980.tb01217.x

Michael Ruta

Papers

Structure of aqueous glutaraldehyde