Abstract:
Curcumin (CUR) and quercetin (QUE) possess low stability owing to their limited solubility in physiological conditions, and hence low bioavailability. This study evaluated polyvinylpyrrolidone (PVP) as a co-stabilizer and coating material to overcome the abovementioned limitations as well as improve the physical stability of fabricated CUR and QUE nanoparticle (NP). CUR and QUE were encapsulated into a pluronic based nanocarrier and co-stabilized with different PVP concentrations (0.1–0.7% w/v). The nanoparticles co-stabilized in different PVP concentrations followed the anomalous Non-Fickian involving both diffusion and swelling controlled transport release behaviors. The fabricated nanoparticles were evaluated for its stability in different pH conditions (pH 5.6 and 7.4 which mimics tumor microenvironment and physiological condition, respectively). The particle sizes, polydispersity index and drug contents did not undergo significant changes at different pH conditions. The effect of storage stability (25 °C/60% RH and 40 °C/75% RH) on CUR and QUE anti-oxidant activity and cellular internalization were also measured at different predetermined time points (up to 3 months). Higher PVP concentration enhanced cellular uptake and permeability into Calu-3 cells as well as stabilized the NP with minimal loss of drug content up to 3 months of storage. As a conclusion, higher PVP concentration as a co-stabilizer was needed to improve the stability of CUR-QUE-NPs for a prolonged period of storage and subsequently retained their antioxidant activities.
