Preparation of Monodispersed Uniform Silica Spheres with Large Pore Size for Fast Adsorption of Proteins

Abstract

In this paper, a “temperature-induced gelation” method, combined with microfluidic flows, has been developed to synthesize the uniform silica spheres with large pore structures for the fast adsorption of bovine serum albumin (BSA). The reversible-thermosentive property of methylcellulose (MC) and auxiliary function of poly(ethylene glycol) (PEG) were introduced to realize a fast gelation in a coaxial microfludic device. The effects of temperature and MC concentration on the gelation process were investigated by monitoring the change of viscosity of sol system over time. The silica spheres with different morphologies of internal structure were synthesized by adjusting the concentration of MC. The prepared silica spheres had large pore volumes (>2.0 mL/g) and an average mesopore diameter of >12 nm. Meanwhile, a large amount of macropores existed in the silica spheres. The bimodal mesopore-marcopore structure resulted in a high protein adsorption capacity (590 mg/g) and a fast adsorption rate (reaching equilibrium within 9 h).