Pharmaceutical nanotechnologyNanostructured biocompatible thermal/electrical stimuli-responsive biopolymer-doped polypyrrole for controlled release of chlorpromazine: Kinetics studies

Biocompatible nanostructured conductive heparin-doped polypyrrole film was fabricated and employed as a high-capacity cation exchanger for programmable release of neuroleptic drug, chlorpromazine (CPZ) with thermally and electrical dual-stimulation. Releasing behavior were studied at different applied potentials and temperatures by in-situ monitoring of UV absorbance measurements. Three mathematical models (Higuchi, Power, and Avrami equation) were employed to investigate kinetics of the release. Based on the obtained results, the Avrami model found to be more comprehensive than two other ones for mathematical description of electro-stimulated release of CPZ. A quantitative relationship between activation energy parameters (Ea, ΔG≠, ΔH≠, and ΔS≠) and release conditions (applied potential and temperature) has been developed and established to predict release rate constants at various applied conditions.

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