Gerda Ratzinger1, Xueyan Wang, Michael Wirth, Franz Gabor. 1. Department of Pharmaceutical Technology and Biopharmaceutics, Faculty of Life Sciences, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria.
Abstract
BACKGROUND: Peroral β-galactosidase preparations for the management of lactose intolerance need to be administered in large doses (1500 to 6000 U) immediately before or together with a lactose-containing meal. AIM: Therefore, this work aimed at developing an innovative long-acting formulation. For this purpose, biodegradable polymeric microcarriers were functionalized with β-galactosidase and targeted with wheat germ agglutinin (WGA) for bioadhesion and thus prolonged residence time in the small intestine. METHODS: Spray-dried poly(D,L-lactide-co-glycolide) (PLGA) particles with 2.78±1.05µm in diameter were functionalized with β-galactosidase from Kluyveromyces lactis and WGA using different types of spacers (polyethyleneimine, hexamethylene diamine, 6-aminocaproic acid) and coupling methods (carbodiimide and glutaraldehyde). The particle-bound enzyme activity was determined, and the bioadhesive characteristics were assessed by interaction with mucin coatings and Caco-2 cell monolayers. RESULTS: Up to 1470 U β-galactosidase per gram PLGA were immobilized. The best results were obtained with hexamethylene diamine as a spacer applying the carbodiimide method. Thereby, a nearly 6-fold increase in enzyme activity was obtained as compared to particles without spacer. Upon targeting with WGA, binding to artificial human intestinal epithelium was increased considerably. CONCLUSIONS: For the delivery of β-galactosidase WGA-targeted PLGA microparticles were prepared, which represent promising candidates for a convenient biomimetic treatment regimen of lactose intolerance.
BACKGROUND: Peroral β-galactosidase preparations for the management of lactose intolerance need to be administered in large doses (1500 to 6000 U) immediately before or together with a lactose-containing meal. AIM: Therefore, this work aimed at developing an innovative long-acting formulation. For this purpose, biodegradable polymeric microcarriers were functionalized with β-galactosidase and targeted with wheat germ agglutinin (WGA) for bioadhesion and thus prolonged residence time in the small intestine. METHODS: Spray-dried poly(D,L-lactide-co-glycolide) (PLGA) particles with 2.78±1.05µm in diameter were functionalized with β-galactosidase from Kluyveromyces lactis and WGA using different types of spacers (polyethyleneimine, hexamethylene diamine, 6-aminocaproic acid) and coupling methods (carbodiimide and glutaraldehyde). The particle-bound enzyme activity was determined, and the bioadhesive characteristics were assessed by interaction with mucin coatings and Caco-2 cell monolayers. RESULTS: Up to 1470 U β-galactosidase per gram PLGA were immobilized. The best results were obtained with hexamethylene diamine as a spacer applying the carbodiimide method. Thereby, a nearly 6-fold increase in enzyme activity was obtained as compared to particles without spacer. Upon targeting with WGA, binding to artificial human intestinal epithelium was increased considerably. CONCLUSIONS: For the delivery of β-galactosidase WGA-targeted PLGA microparticles were prepared, which represent promising candidates for a convenient biomimetic treatment regimen of lactose intolerance.
Authors: Luca Casettari; Enzo Castagnino; Snjezana Stolnik; Andrew Lewis; Steven M Howdle; Lisbeth Illum Journal: Pharm Res Date: 2011-03-11 Impact factor: 4.200