Preparation of Bovine Serum Albumin (BSA) nanoparticles by desolvation using a membrane contactor: A new tool for large scale production

Abstract

Albumin nanoparticles are attractive drug delivery systems as they can be prepared under soft conditions and incorporate several kinds of molecules. The aim of this study was to upscale the desolvation process for preparing Bovine Serum Albumin (BSA) nanoparticles using a membrane contactor. At a first step, the BSA nanoparticles were prepared at small scale using a syringe pump. BSA nanoparticles of 139nm in size, with a polydispersity index of 0.046, were obtained at the optimal conditions: pH 8.2, 100mgmL−1 BSA albumin solution (2mL), and 1mLmin−1 flow rate of ethanol addition (8mL). The upscaling with a membrane contactor was achieved by permeating ethanol through the pores of a Shirasu Porous Glass (SPG Technology Co., Japan) membrane and circulating the aqueous phase tangentially to the membrane surface. By increasing the pressure of the ethanol from 1 to 2.7 bars, a progressive decrease in nanoparticle size was obtained with a high nanoparticles yield (around 94–96%). In addition, the flow rate of the circulating phase did not affect the BSA nanoparticle characteristics. At the optimal conditions (pH 8.2, 100mgmL−1 BSA albumin solution, pressure of ethanol 2.7 bars, flow rate of the circulating phase 30.7mLs−1), the BSA nanoparticles showed similar characteristics to those obtained with the syringe pump. Large batches of BSA nanoparticles were prepared up to 10g BSA. The BSA nanoparticles were stable at least during 2months at 4°C, and their characteristics were reproducible. It was then concluded that the membrane contactor technique could be a suitable method for the preparation of albumin nanoparticles at large scale with properties similar to that obtained at small scale.