Response Surface Optimization of Catechin Liposomes Preparation Using the Rapid Expansion of Supercritical Solution Process

Phospholipid liposomes are a promising drug delivery system. Catechin, a hydrophilic drug, was used to prepare catechin liposomes through a modified rapid expansion of supercritical solution (RESS) process in this study. The influences of operation parameters (i.e., temperature, pressure, and mass ratio of liposomal materials to catechin) on the properties of the prepared liposomes were determined using the single-factor analysis. The process was further optimized by response surface methodology (RSM) based on the Box-Behnken design (BBD). The encapsulation efficiency (EE) values can be adequately predicted using the obtained equation. The maximum EE value can reach 61.36±0.68% under the optimal parameters (i.e., the expansion temperature, pressure, and p/c mass ratio were 56.34 °C, 19.99 MPa, and 5.99, respectively). The prepared liposomes can effectively protect and stabilize the loaded catechin effectively. In addition, the in vitro release study showed the slow and sustained release behavior of the catechin liposomes.