title: An optimized gastroretentive nanosystem for the delivery of levodopa.
abstract: Characterization of the physicochemical and physicomechanical properties as well as biopharmaceutical suitability of a drug delivery system is needful in optimization of the formulation and manufacturing processes in order to achieve the desired responses. Interpolymeric blend (IPB) nano-enabled gastroretentive levodopa-loaded drug delivery systems were formulated, optimized and characterized using techniques such as spectroscopy, calorimetry, density, textural analysis, morphological analysis, porosity analysis and magnetic resonance imaging. The in vitro drug release of the delivery systems was compared to those of the conventional dosage forms and in vivo absorption was predicted. The average densities were 1.41 mg/mm(3) and 1.56 mg/mm(3) for the two formulations; rigidities were 75.05 N/mm and 84.93 N/mm; and 92% of the pores of the IPB drug delivery system were mesoporous. MR imaging displayed the swollen front at pH 1.5 and the eroded front at pH 4.5. In comparisons to the conventional dosage forms, the IPB nano-enabled gastroretentive levodopa-loaded drug delivery systems exhibited drug release over a prolonged period of time and levodopa-loaded IPB matrices were the best fit for zero-order release. Indeed the analyses of IPB nano-enabled gastroretentive levodopa-loaded drug delivery systems indicate that they hold promise as sustained delivery system for management of Parkinson's disease.
authors.affiliation: Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health 5 Sciences, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown 2193, South Africa.
authors.forename: Ndidi C
authors.initials: NC
authors.lastname: Ngwuluka
authors.affiliation: Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health 5 Sciences, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown 2193, South Africa.
authors.forename: Yahya E
authors.initials: YE
authors.lastname: Choonara
authors.affiliation: Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health 5 Sciences, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown 2193, South Africa.
authors.forename: Pradeep
authors.initials: P
authors.lastname: Kumar
authors.affiliation: Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health 5 Sciences, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown 2193, South Africa.
authors.forename: Lisa C
authors.initials: LC
authors.lastname: du Toit
authors.affiliation: Department of Neurology, Division of Neurosciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown 2193, South Africa.
authors.forename: Girish
authors.initials: G
authors.lastname: Modi
authors.affiliation: Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health 5 Sciences, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown 2193, South Africa. Electronic address: viness.pillay@wits.ac.za.
authors.forename: Viness
authors.initials: V
authors.lastname: Pillay
mesh_terms: D002626:Chemistry, Pharmaceutical / Q000379:methods; D003692:Delayed-Action Preparations / Q000737:chemistry*; D004304:Dosage Forms; D016503:Drug Delivery Systems / Q000379:methods; D065546:Drug Liberation; D006863:Hydrogen-Ion Concentration; D007980:Levodopa / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods; D011108:Polymers / Q000737:chemistry; D016062:Porosity; D013270:Stomach / Q000187:drug effects*
chemical_list: D003692:Delayed-Action Preparations; D004304:Dosage Forms; D011108:Polymers; D007980:Levodopa
keywords: Controlled release; Drug delivery; Gastroretention; Interpolyelectrolyte complex; Magnetic resonance imaging (MRI); Nanoparticles; Polymers