Supercritical-CO2 Assisted Electrospray to Produce Cellulose Acetate+rutin Micro-carriers

Abstract

Supercritical-CO2 assisted electrospray is a new process used to produce polymeric micro- and nanoparticles characterized by tunable and regular morphologies. The major innovation consists of the addition of supercritical CO2 to the polymeric solution, obtaining a gas expanded liquid having reduced values of viscosity and surface tension. Due to its biodegradability and biocompatibility, cellulose acetate (CA) was selected as polymeric carrier for microparticles production, that can be used for drug delivery applications. Indeed, CA solutions were loaded with a poorly-water soluble compound, rutin (RUT), to improve its bioavailability. The experiments were performed at different CA concentrations (0.5 and 1 wt%) and different RUT concentration, that was varied from 2.5 to 7.5 wt% with respect to CA; the applied voltage was set at 30 kV. CA/RUT microparticles were successfully produced; working at 140 bar and 30 kV, particles characterized by an average diameter of 980±120 nm and networked fibers were obtained, processing 1 wt% CA solution and using a RUT concentration of 7.5 wt% with respect to CA. IR spectroscopy revealed the physical dispersion of RUT into CA particles.