Controlled Release Coating of Aqueous Ethyl Cellulose Dispersion Combined with DifferentGrades of Hydroxypropyl Methylcellulose

摘要

Three grades of hydroxypropyl methylcellulose(HPMC E5, E15 and E50), Methocel?, had been added tothe aqueous ethyl cellulose dispersion, Surelease?, tomodify the release profile of the coated multiparticulatedosage form. The influence of coating levels, molecularweight of HPMC and curing effect were investigated. Thedissolution rate decreased with the increase of coatinglevel. The higher ratio of HPMC/EC led to fast dissolutionfor all three grades of HPMC. The dissolution profiledemonstrated that at the same coating level and with thesame HPMC/EC ratio, pellets coated with HPMC-E15showed the lowest release rate and pellets with HPMC E5exhibited the slowest release profile, which did notcorrelate with the molecular weight/viscosity rank of E5,E15 and E50. The curing study exhibited that there isvarying pattern for the release change after curing. Thepellets coated with 7.5% HPMC-E15 had a fasterdissolution after curing; however, the pellets with 10%HPMC E15 had a slightly slower release after curing.