Glutaraldehyde amino group reaction

A popular cross-linking agent for chitosan is glutaraldehyde, as proposed by Muzzarelli et al. [217]. Chitosan networks were obtained by reaction with glutaraldehyde in lactic acid solution (pH 4-5) at molar ratio amino groups/carbonyl functions about 10-20 reduction gave stable chemical gels. 

Formaldehyde, sulphur dioxide and glutaraldehyde react with amino groups. If these groups are essential for metabolic activity, cell death will follow reactions of this nature. Chlorinated fso-thiazolones as well as acting on -SH groups, (Section 3.4), can react with -NH2 groups. 

An additional reaction reported for adenine involves the coupling of glutaraldehyde to the 6-amino group (Matthews and Kricka, 1988). However, reaction at this group with electrophilic reagents such as those discussed in Section 2 proceeds more slowly than that possible... 

Fig.1 Schematic illustration of the immobilization of penicillin G acylase on glutamate-pillared LDHs. Reaction of the primary amino groups of the intercalated glutamate ions with glutaraldehyde through Schiff s base formation is followed by covalent coupling of the residual aldehyde groups with the free amino groups of the enzyme...

The enzymes commonly used as labels in ELISA and other immunochemical reactions include horse radish peroxidase (HRP) and alkaline phosphatase (AP). The enzyme can be covalently coupled to the antibody using glutaraldehyde conjugation to reactive amino groups on the enzyme (lysines) in a phosphate buffered aqueous solution at neutral pH, as shown in Fig. 19 (103). Alternatively, carbohydrates present in the immunoglobulin structure can be cleaved by periodate treatment (see Fig. 20) and bound to free amino groups on the enzyme through a Schiff base reaction (103). 

Lanthanide-labeled oligonucleotide probes are now available commercially (161). Oligonucleotides are synthesized containing free amino groups, which are then labeled with a lanthanide chelate via a Schiff base conjugation [similar to the reaction shown in Fig. 19 but with a monoaldehyde functional group (linker) of a lanthanide complex in place of glutaraldehyde]. b. 

Amino groups on proteins may be reacted with the bis-aldehyde compound glutaraldehyde to form activated derivatives able to cross-link with other proteins. The reaction mechanism for this modification proceeds by one of several possible routes. In the first option, one of the aldehyde ends can form a Schiff base linkage with e-amines... 

We have also developed a chemistry that allows us to attach the Fab to only the inner surfaces of the nanotubes. While still within the pores of the template membrane, the inner surfaces were treated with 3-aminopropyltrimethoxysilane. The template membrane was then dissolved and the amino sites on the inner surfaces were coupled to free amino groups on the Fab fragment using the well-known glutaraldehyde coupling reaction [4]. When 18 mg of these interior-only Fab-modified nanotubes were incubated with 1 mL of a 10 pM racemic mixture of the drug, 80% of the RS (and none of the SR) enantiomer was extracted. 

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