Crosslinking methods

Since immunotoxin conjugates are destined to be used in vivo, their preparation involves more critical consideration of crosslinking methods than most of the other conjugation protocols described in this book. The following sections discuss the problems associated with toxin conjugates and the main crosslinking methods for preparing them. 

This multi-step crosslinking method employing SPDP on both molecules has been used to prepare a number of immunotoxin conjugates (Edwards et al., 1982 Thorpe et al., 1982 Colombatti et al., 1983 Wiels et al., 1984 Vogel, 1987 Reiter and Fishelson, 1989). While... 

The ionizing method is restricted to small pieces and is thus of limited use. In contrast, the chemical crosslinking method has found more commercial applicability. 

The preparation of cytotoxic antibody-A chain conjugates using chemical crosslinking methods has two main requirements. First, the number of crosslinkers introduced per antibody molecule should be low. This minimizes the risk that the antigen-binding capability of the antibody will be compro-... 

THe network structure of these block polymers can also be altered by actually crosslinking the elastomeric polydiene chains, thus introducing a chemical network. In this approach it was necessary to use a crosslinking method which would not result in any measurable chain scission. Dicumyl peroxide (Dicup) was chosen for crosslinking an SIS polymer since this peroxide is known to accomplish exclusive crosslinking without any observable chain scission (3). The Dicup was dissolved in a THF solution of the polymer, and a cast film was prepared which was then vulcanized in a press at 155 °C for 35 min. A control sample, without Dicup was treated in the same way. 

Many silicones grafted with organic entities are commercially available and others can be synthesized [50] giving rise to numerous organic crosslinking methods, only those involved in IPNs will be discussed in this review. 

The finishes obtained with FIXAPRET PEC have good hydrolysis stability. When the product is applied by the dry curing or the moist crosslinking method, the finish has no tendency to retain chlorine. The product does not impair the shade or the light fastness of coloured goods. 

Other control parameters included both chemical reactions and physical interactions (Figure 9). Variation of these properties caused a concomitant change in mechanical properties and water absorption. Such control eillows the composite to be "tailored to a specific use. This material can be easily fabricated and adapted to a number of different socket geometries while allowing bone growth into the porous material. Initial studies have shown that neither the biocompatibility of the material nor the resistance to body fluid diffusion are affected to a major extent by this crosslinking method. Long term implantation studies are presently underway to determine the ultimate effect of the material on the implant area. 

Crosslinking of polyethylen and its copolymers EPM, EPDM, and EVA is mainly carried out by radicals generated from organic peroxides. Other crosslinking methods like electron-beam radiation and grafting of vinylsUanes assume a smaller role in this process. 

Hennink WE, Van Nostrum CF. Novel crosslinking methods to design hydrogels. Adv Drug Deliv Rev 2002 54 13-36. 

Ldpez-Gallego F, Betancor L, Hidalgo A et al. (2005) Preparation of a robust biocatalyst of D-amino acid oxidase on Sepabeads supports using the glutaraldehyde crosslinking method. Enzyme Microb Technol 37 750-756... 

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