Supercritical CO2 assisted electrospray of PVP-Rutin mixtures using a liquid collector

In this work, supercritical CO2 assisted electrospray is used to produce micro- and nanoparticles of polyvinylpyrrolidone (PVP) loaded with rutin (RUT), testing a new kind of collection system. The adoption of a liquid collector allowed a more accurate capture of the electrosprayed PVP/RUT particles that were generally smaller than the ones collected using an aluminum foil, maintaining constant all of the other operating parameters. In particular, PVP/RUT particles mean diameter ranged from 290 ± 115 nm for 3 % w/w PVP loaded with 3.5 % w/w RUT/PVP to 943 ± 216 nm for 3 % w/w PVP loaded with 10 % w/w RUT/PVP. RUT dissolution rate increased up to 6 times and periodic dynamic light scattering analysis allowed the measurement of RUT nanoparticles formed inside the PVP microparticles, whose mean diameter was 140 ± 14 nm.