title: Characterizations of plasticized polymeric film coatings for preparing multiple-unit floating drug delivery systems (muFDDSs) with controlled-release characteristics.
abstract: Effervescent multiple-unit floating drug delivery systems (muFDDSs) consisting of drug (lorsartan)- and effervescent (sodium bicarbonate)-containing pellets were characterized in this study. The mechanical properties (stress and strain at rupture, Young's modulus, and toughness) of these plasticized polymeric films of acrylic (Eudragit RS, RL, and NE) and cellulosic materials (ethyl cellulose (EC), and Surelease) were examined by a dynamic mechanical analyzer. Results demonstrated that polymeric films prepared from Surelease and EC were brittle with less elongation compared to acrylic films. Eudragit NE films were very flexible in both the dry and wet states. Because plasticizer leached from polymeric films during exposure to the aqueous medium, plasticization of wet Eudragit RS and RL films with 15% triethyl citrate (TEC) or diethyl phthalate (DEP) resulted in less elongation. DEP might be the plasticizer of choice among the plasticizers examined in this study for Eudragit RL to provide muFDDSs with a short time for all pellets to float (TPF) and a longer period of floating. Eudragit RL and RS at a 1∶1 ratio plasticized with 15% DEP were optimally selected as the coating membrane for the floating system. Although the release of losartan from the pellets was still too fast as a result of losartan being freely soluble in water, muFDDSs coated with Eudragit RL and RS at a 1∶1 ratio might have potential use for the sustained release of water-insoluble or the un-ionized form of drugs from gastroretentive drug delivery systems.
authors: School of Pharmacy, College of Pharmacy, Taipei Medical University, Taipei, Taiwan.
authors: Sheng-Feng
authors: SF
authors: Hung
authors: School of Pharmacy, College of Pharmacy, Taipei Medical University, Taipei, Taiwan; Department of Cosmetic Science, Providence University, Taiwan Boulevard, Shalu, Taichung, Taiwan, ROC.
authors: Chien-Ming
authors: CM
authors: Hsieh
authors: School of Pharmacy, College of Pharmacy, Taipei Medical University, Taipei, Taiwan.
authors: Ying-Chen
authors: YC
authors: Chen
authors: School of Pharmacy, College of Pharmacy, Taipei Medical University, Taipei, Taiwan.
authors: Yu-Chun
authors: YC
authors: Wang
authors: School of Pharmacy, College of Pharmacy, Taipei Medical University, Taipei, Taiwan.
authors: Hsiu-O
authors: HO
authors: Ho
authors: School of Pharmacy, College of Pharmacy, Taipei Medical University, Taipei, Taiwan; Clinical Research Center and Traditional Herbal Medicine Research Center, Taipei Medical University Hospital, Taipei, Taiwan.
authors: Ming-Thau
authors: MT
authors: Sheu
mesh_terms: D002482:Cellulose / Q000031:analogs & derivatives / Q000737:chemistry; D003692:Delayed-Action Preparations; D004337:Drug Carriers / Q000737:chemistry*; D019808:Losartan / Q000737:chemistry; D008567:Membranes, Artificial; D010969:Plastics / Q000737:chemistry*; D017693:Sodium Bicarbonate / Q000737:chemistry; D013314:Stress, Mechanical
chemical_list: D003692:Delayed-Action Preparations; D004337:Drug Carriers; D008567:Membranes, Artificial; D010969:Plastics; C013517:ethyl cellulose; D017693:Sodium Bicarbonate; D002482:Cellulose; D019808:Losartan