title: Optimising the incorporation and release of a neurotrophic factor using conducting polypyrrole.
abstract: In this study, a neurotrophin delivery system based on an inherently conducting polymer (ICP) has been developed. Direct incorporation of neurotrophin-3 (NT-3) was investigated and controlled release was tested under various electrochemical conditions. The loading capacity and amount of NT-3 released from the polymer was determined using (125)I-labelled NT-3. Electrochemical stimulation of polypyrrole by pulsed voltage, pulsed current or cyclic voltammetry promoted the release of NT-3 at a greater rate than natural diffusion of NT-3. NT-3 was released from polypyrrole as an initial burst in the first 24 h followed by prolonged release over a subsequent 6 days of sampling. The amount of NT-3 incorporated into the polymer could be controlled by varying the polymerisation time, with longer growth periods incorporating more NT-3. The NT-3 release results indicated that the polymers grown for longer released a lower percentage of the incorporated NT-3 compared to the polymers grown for shorter times. Polymer-based neurotrophin delivery systems have the potential to be incorporated into future treatments for nerve injuries to prevent nerve degradation and promote nerve protection.
authors.affiliation: ARC Centre of Excellence for Electromaterials Science, University of Wollongong, Northfields Avenue, Wollongong, NSW 2522, Australia.
authors.forename: Brianna C
authors.initials: BC
authors.lastname: Thompson
authors.forename: Simon E
authors.initials: SE
authors.lastname: Moulton
authors.forename: Jie
authors.initials: J
authors.lastname: Ding
authors.forename: Rachael
authors.initials: R
authors.lastname: Richardson
authors.forename: Adrian
authors.initials: A
authors.lastname: Cameron
authors.forename: Stephen
authors.initials: S
authors.lastname: O'Leary
authors.forename: Gordon G
authors.initials: GG
authors.lastname: Wallace
authors.forename: Graeme M
authors.initials: GM
authors.lastname: Clark
mesh_terms: D003692:Delayed-Action Preparations; D004337:Drug Carriers / Q000737:chemistry*; D004339:Drug Compounding; D004563:Electrochemistry; D007457:Iodine Radioisotopes; D046529:Microscopy, Electron, Transmission; D015394:Molecular Structure; D020933:Neurotrophin 3 / Q000008:administration & dosage* / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D011758:Pyrroles / Q000737:chemistry*; D012995:Solubility; D013499:Surface Properties; D013997:Time Factors
chemical_list: D003692:Delayed-Action Preparations; D004337:Drug Carriers; D007457:Iodine Radioisotopes; D020933:Neurotrophin 3; D011108:Polymers; D011758:Pyrroles; C067635:polypyrrole