title: Design of chitospheres loaded with pristine polymer particles for extended drug delivery via polyelectrolyte complexation and particulate leaching.
abstract: The aim of this study was to investigate the drug release from swellable chitospheres laden with pristine polymethylmethacrylate (PMMA) nanoparticles. Chitosan matrices were prepared by sodium tripolyphosphate crosslinking from a chitosan suspension containing the model BCS class II drug, indomethacin. PMMA particles were added to the chitospheres as the modulator for drug release. Swelling and erosion studies in conjunction with textural profiling provided an understanding of the dominant and underlying drug release mechanisms of the ionically crosslinked chitospheres loaded with the pristine PMMA particles. A series of drug release studies performed in PBS pH 7.4 showed that the pristine particle-loaded chitospheres released indomethacin over 144 h in a first-order manner with 50% drug release occurring over 48 h. The study also revealed that in situ porogen leaching for pore creation and polyelectrolyte complex formation were the main mechanisms of release from the chitospheres. The results of this study may be utilized for the development of neuro-implants for controlled delivery of bioactives to the brain where scaffolds of superior mechanical strength and reduced swelling properties are required.
authors.affiliation: Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown, 2193, South Africa.
authors.forename: Poornima
authors.initials: P
authors.lastname: Ramburrun
authors.affiliation: Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health 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 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 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: Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health 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: D048271:Chitosan / Q000737:chemistry*; D016503:Drug Delivery Systems; D065546:Drug Liberation; D007213:Indomethacin / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D019904:Polymethyl Methacrylate / Q000737:chemistry; D011122:Polyphosphates / Q000737:chemistry; D016062:Porosity; D013499:Surface Properties; D013818:Thermogravimetry
chemical_list: D011122:Polyphosphates; D019904:Polymethyl Methacrylate; D048271:Chitosan; C005692:triphosphoric acid; D007213:Indomethacin
keywords: Chitosan; Controlled drug release; Drug release mechanisms; In situ leaching; Polyelectrolyte complex; Polymethyl methacrylate