title: An experimental investigation of enzyme release from poly(vinyl alcohol) crosslinked microspheres.
abstract: Crosslinked poly(vinyl alcohol) particles were prepared by the addition of glutaraldehyde into a PVA methanol/water solution in the presence of 0.2 N sulphuric acid. The polymer solution was dispersed in mineral oil in a jacketed vessel, with the aid of a six-blade impeller. Spherical crosslinked particles in the size range 30-80 microns were obtained by varying the degree of agitation or/and the amount of suspending agent. The crosslinked particles, after washing and drying, were placed into a protease enzyme solution for loading. The enzyme-containing water-swollen particles were subsequently removed from the solution and the enzyme release kinetics determined by a UV spectrophotometer. The influence of the degree of crosslinking, ionic strength, pH, particle size, and degree of hydrophilicity of the polymer on the enzyme activity was retained during the adsorption-desorption studies. The release behaviour of enzymes from crosslinked PVA particles exhibited a biphasic kinetic model, with an initial fast release followed by a much slower release rate.
authors.affiliation: Department of Chemical Engineering and Chemical Process Engineering, Aristotle University of Thessaloniki, Greece.
authors.forename: A R
authors.initials: AR
authors.lastname: Bachtsi
authors.forename: C
authors.initials: C
authors.lastname: Kiparissides
mesh_terms: D002214:Capsules / Q000302:isolation & purification*; D003432:Cross-Linking Reagents; D003692:Delayed-Action Preparations; D004339:Drug Compounding / Q000379:methods; D010450:Endopeptidases / Q000008:administration & dosage / Q000493:pharmacokinetics; D004798:Enzymes / Q000008:administration & dosage* / Q000493:pharmacokinetics; D005782:Gels; D005976:Glutaral; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D007700:Kinetics; D008855:Microscopy, Electron, Scanning; D008956:Models, Chemical; D010316:Particle Size; D011142:Polyvinyl Alcohol
chemical_list: D002214:Capsules; D003432:Cross-Linking Reagents; D003692:Delayed-Action Preparations; D004798:Enzymes; D005782:Gels; D011142:Polyvinyl Alcohol; D010450:Endopeptidases; D005976:Glutaral