A Comparative Study of Progesterone and Lidocaine Hydrochloride Release from Poly(L-lactide) Films

Polyesters have been attractive for development of drug delivery applications because of their biocompatible, biodegradable and non-toxic properties. The objective of work is a comparative study on the release characteristics of two drugs loaded poly (L-lactide) (PLLA) film. Progesterone (Pro) and lidocaine hydrochloride (LidH) were chosen as the hydrophobic and hydrophilic model drugs, respectively. The PLLA films containing drugs (10% w/w) were prepared using the solvent casting method after dissolution in dichloromethane. The PLLA matrices were evaluated by scanning electron microscopy (SEM) and dynamic mechanical thermal analysis (DMTA). In vitro drug release studies were carried out at 37°C in ethanol/water for progesterone and phosphate buffer (pH 7.4) for LidH. The release kinetics were explained using Higuchi, Korsmeyer-Peppas and Gallagher-Corrigan equations. In vitro drug release was found to be controlled by a triphasic profile for LidH and biphasic profile for progesterone. The results revealed that drug release was higher for the LidH-PLLA film than the progesterone- PLLA film. SEM images confirmed that LidH-PLLA film degraded more than did progesterone- PLLA film. The results of DMTA demonstrated a slight drug-polymer interaction. The experimental results of drug release approximated three commonly-used semi-empirical models: Higuchi, Korsmeyer-Peppas and Gallagher-Corrigan equations. The R2 values show that these mathematic models are suitable for describing progesterone and LidH release from PLLA film.