Preparation and Evaluation of Chitosan Submicroparticles Containing Pilocarpine for Glaucoma Therapy.
The objective of the present study was to optimize the preparation of chitosan submicroparticles and to assess whether they enhanced ocular permeation of pilocarpine. Submicroparticles were produced by spray drying and characterized to determine process yield, encapsulation efficiency, morphology, size distribution, drug-polymeric matrix interaction, porcine sclera permeation as well as ocular irritancy and drug retention. Quantification of pilocarpine using High Performance Liquid Chromatography was found to be selective, linear, precise, accurate and robust. The spray drying method proved to be simple and reproducibly produced particles with satisfactory yields, thus showing potential for industrial scale applications. The pilocarpine-loaded chitosan particles exhibited adequate morphological characteristics as well as high encapsulation efficiency. The particles produced were on a submicrometric scale and compatible with intraocular administration. In pilocarpine-loaded particles, the interaction between pilocarpine and chitosan polymeric matrix resulted in delayed release of the drug, attributed to formation of a reservoir system. The best fit for drug release was obtained using the Higuchi equation. The chitosan submicroparticles enhanced the permeation effect and increased the passage of pilocarpine through porcine sclera and also demonstrated low irritancy potential. Therefore, the particles produced can be considered a promising system for the ocular delivery of pilocarpine.
Cleonice Marques
CM
Costa
Leticia Coli
LC
Louvisse de Abreu
Elisabete Pereira
EP
dos Santos
Octavio Augusto
OA
Franca Presgrave
Anna Paola Trindade
AP
Rocha Pierucci
Carlos Rangel
CR
Rodrigues
Valeria Pereira
VP
de Sousa
Sara
S
Nicoli
Eduardo
E
Ricci Junior
Department of Drugs and Pharmaceutics, Faculty of Pharmacy, Federal University of Rio de Janeiro. Av. Carlos Chagas Filho, 373, CCS, Rio de Janeiro, RJ, 21941-902, Brazil. lmcabral@pharma.ufrj.br.
Lucio Mendes
LM
Cabral
D000818:Animals; D048271:Chitosan / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D004337:Drug Carriers / Q000138:chemical synthesis* / Q000737:chemistry*; D005901:Glaucoma / Q000188:drug therapy*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D010316:Particle Size; D010862:Pilocarpine / Q000008:administration & dosage* / Q000627:therapeutic use*; D013499:Surface Properties; D013552:Swine
D004337:Drug Carriers; D010862:Pilocarpine; D048271:Chitosan