Covalent crosslinking with various crosslinkers, such as adipic acid dihydrazide and lysine, can be employed to overcome this uncontrolled degradation.
Protein crosslinking with bi- and multifunctional crosslinkers leads to the incorporation of molecular spacer groups of defined length and composition between the reaction partners.
These preliminary studies clearly demonstrated the ability of these multifunctional crosslinkers to result in tight nanosized networks with biocompatible polymers such as PEG and their potential to carry chemotherapeutic drugs.
Thus, the increased temperature in the thermal curing process enhances the effectiveness of the HSPs as multifunctional crosslinkers leading to higher curing rates and crosslinking density, whereas in photocuring the flexibilization effect can be enhanced by having high gel content at lower epoxy group conversion.
Crosslinked polymeric systems can be prepared by chemical crosslinking of the polymeric matrices in the presence of various crosslinkers such as ethyleneglycol dimethacrylate (EGDMA), polycaprolactone (PCL) diacrylate, methyl methacrylate (MMA), divinyl benzene (DVB), pentaerythritol triacrylate (PETA), pentaerythritol tetraacrylate, etc.
These functional groups can react with many bifunctional small molecule crosslinkers, such as glutaraldehyde, formaldehyde, genepin, diethyl squarate and diacrylate, to form chemically crosslinked hydrogels.
The multifunctional dendrimers were introduced as novel multifunctional crosslinkers after the activation of the carboxylic acid groups of glutamic and aspartic acid residues in collagen.
Photopolymerizations were carried out using monofunctional monomers methyl or ethyl- α-hydroxymethyl)acrylatethyl- α-hydroxymethylethyl- α-hydroxymethylnctionacrylatelinkers.
The effects of crosslinkers, such as formaldehyde, genipin and ethyl- dimethyl aminopropyl) and carbodiimidethyl- dimethyl (EDaminopropylso been evandated.
Additionally, there are a few examples of multifunctional crosslinkers that can be used to target proteins at more than two functional groups simultaneously.
