Polymers polymer-enzyme inhibitor conjugates

Trypsin Polyacrylic acid, thiomers, polymer-enzyme-inhibitor conjugates Luessen et al. (1996b)... 

Elastase Polymer-enzyme-inhibitor conjugates Guggi and Bernkop-Schniirch (2003) and Marschiitz and Bernkop-Schniirch (2000)... 

As demonstrated in a number of studies, the inhibitory activity of mucoadhesive polymers can be extensively improved by the immobilization of enzyme inhibitors onto the polymer without markedly influencing the mucoadhesive properties of the polymer. Such conjugates, comprising a mucoadhesive polymer and a covalently bound enzyme inhibitor exhibit diverse... 

Nevertheless, the use of bacitracin as an enzyme inhibitor in order to improve drug uptake in vivo remains questionable, because bacitracin-mediated nephrotoxicity has been reported previously (Drapeau et al. 1992). However, it was demonstrated recently that bacitracin can be covalently bond to a mucoadhesive, non-absorbable polymer and that this polymer-bacitracin conjugate still retains its inhibitory activity (Bernkop-Schnurch and Marschiitz 1997). The reason for using such a polymer-inhibitor conjugate instead of unmodified bacitracin is that the polymer-bacitracin conjugate is believed to remain in the GI tract which would exclude systemic side effects. More information about polymer-inhibitor conjugates are provided in Section 4.4.6.3 of this article. 

Luessen HL, Verhoef JC, Borchard G, Lehr CM, de Boer AG, Junginger HE (1995) Mucoadhesive polymers in peroral peptide drug delivery. II. Carbomer and polycarbophil are potent inhibitors of the intestinal proteolytic enzyme trypsin. Pharm Res 12 1293-1298 Marschutz MK, Bernkop-Schnurch A (2000) Oral peptide drug delivery polymer-inhibitor conjugates protecting insulin from enzymatic degradation in vitro. Biomaterials 21 1499-1507... 

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