Glutaraldehyde cross-linking

En2yme techniques are primarily developed for commercial reasons, and so information about immobilisation and process conditions is usually Limited. A commercially available immobilised penicillin V acylase is made by glutaraldehyde cross-linking of a cell homogenate. It can be used ia batch stirred tank or recycled packed-bed reactors with typical operating parameters as iadicated ia Table 2 (38). Further development may lead to the creation of acylases and processes that can also be used for attaching side chains by ensymatic synthesis. 

In view of the conductive and electrocatalytic features of carbon nanotubes (CNTs), AChE and choline oxidases (COx) have been covalently coimmobilized on multiwall carbon nanotubes (MWNTs) for the preparation of an organophosphorus pesticide (OP) biosensor [40, 41], Another OP biosensor has also been constructed by adsorption of AChE on MWNTs modified thick film [8], More recently AChE has been covalently linked with MWNTs doped glutaraldehyde cross-linked chitosan composite film [11], in which biopolymer chitosan provides biocompatible nature to the enzyme and MWNTs improve the conductive nature of chitosan. Even though these enzyme immobilization techniques have been reported in the last three decades, no method can be commonly used for all the enzymes by retaining their complete activity. 

Fig. 2.19 Glutaraldehyde cross-linking of enzyme E with bovine serum albumin (BSA), followed by Li borohydride stabilization...

Bulk ink incorporation followed by glutaraldehyde cross-linking Prussian blue - 200 4 0 - Pravda et al. [22]... 

Figure 25. Electron spectra from glutaraldehyde cross-linked chitosan.

The first reported preparation of cross-linked enzyme crystals was by Quiocho and Richards in 1964 [1], They prepared crystals of carboxypeptidase-A and cross-linked them with glutaraldehyde. The material they prepared retained only about 5% of the activity of the soluble enzyme and showed a measurable increase in mechanical stability. The authors quite correctly predicted that cross-linked enzyme crystals, particularly ones of small size where the diffusion problem is not serious, may be useful as reagents which can be removed by sedimentation and filtration. Two years later the same authors reported a more detailed study of the enzymic behavior of CLCs of carboxypeptidase-A [2], In this study they reported that only the lysine residues in the protein were modified by the glutaraldehyde cross-linking. The CLCs were packed in a column for a flow-through assay and maintained activity after many uses over a period of 3 months. 

McIntosh, D.B. (1992). Glutaraldehyde cross-links Lys-492 and Arg-678 at the active site of sarcoplasmic reticulum Ca2+-ATPase. J. Biol. Chem. 267, 22328-22335. 

Liang ZP, Feng YQ, Meng SX et al (2005) Preparation and properties of urease immobilized onto glutaraldehyde cross-linked chitosan beads. Chin Chem Lett 16 135-138... 

Glutaraldehyde Cross-linking of proteins in cell envelope (q. v.) and elsewhere in cel ... 

The non-aqueous lipase system for flavor esters developed by our group used components and preparative techniques for enzyme immobilization, that would not only be cost effective and simple but also meet regulatory requirements. The enzyme could have been immobilized by a number of methods however for the Intended application only (i) adsorption (11) ionic bonding or (lii) glutaraldehyde cross-linking would be... 

Kikuchi, M., Matsumoto, M., Yamada, T., Koyama, Y, Takakuda, K., and Tanaka, J., Glutaraldehyde cross-linked hydroxyapatite/collagen self-organized nanocomposites, Biomaterials, 25, 63, 2004. 

Ezpeleta, I. Irache, J.M. Gueguen, J. Orecchioni, A.M. Properties of glutaraldehyde cross-linked vicilin nano- and microparticles. J. Microencapsulation 1997,14 (5), 557-565. 

Collagen is a natural fibrous protein found in human cartilage, connective tissue, and bone. Glutaraldehyde cross-linked bovine collagen is a sterile, biocompatible, biodegradable, purified bovine dermocollagen cross-linked with glutaraldehyde, mixed in a phosphate-buffered saline solution. 

Administration of erythrocytes can cause neutrophil priming, which leads to a dysfunctional inflammatory response. This neutrophil priming, which has been associated with the occurrence of multiple organ failure after trauma, was not observed after administration of Polyheme, a glutaraldehyde-cross-linked hemoglobin prodnct (3). 

The characteristics of QCM sensors containing mono- or multilayered DNA probe constructed by direct chemical bonding, avidin-biotin interaction or electrostatic adsorption on polyelectrolyte films were compared by Zhou et al. [60]. The use of the polyethyleneimine adhesion, glutaraldehyde cross-linking (PEI-Glu) method to immobilize hepatitis B virus DNA onto gold QCM quartz crystals, enabling the sensor to be regenerated five times, was reported by Hu and co-workers [61],... 

Bigi, A., Cajazzi, G., Panzavolta, S., Rubini, K., and Roveri, N. (2001). Mechanical and thermal properties of gelatin films at different degree of glutaraldehyde cross-linking. Biomaterials 22, 763-768. 

Schoevaart, R., Siebum, A., van Rantwijk, F., Sheldon, R., and Kieboom, T. (2005) Glutaraldehyde cross-link analogues from carbohydrates. Starch/ Starke, 57, 161-165. 

P-Glucuronidase Retention of function after glutaraldehyde cross-linking More resistant to glutaraldehyde and formaldehyde... 

Electrodeposition of glucose oxidase and bovine semm albumin on a platinum black electrode followed by glutaraldehyde cross-linking and covered with a polyethylene glycol-polyurethane outer membrane Blood glucose [38]... 

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