Generation of Ca-Alginate Microcapsules with Different Concentrations in a Microfluidic Fusion Chip

Abstract

This paper presents a micro fluidic fusion chip for generating Ca-alginate microcapsules with different concentrations. Using MEMS technology, we designed and fabricated a PDMS microfluidic chip, which contained a micron rating 3D electrode as a replacement for the planar electrode made of indium tin oxide, a pillar-induced fusion zone, and an s-shaped observation zone. We used this microfluidic chip to generate Ca-alginate microcapsules uniformly sized but covered in different bovine serum albumin (BSA) concentrations, and found that the sizes ranged between $\mathbf{181 \mu \mathrm{m}}$ and $\mathbf{161 \mu \mathrm{m}}$ . After putting the three differently-sized microcapsules and three different BSA concentrations into Phosphate Buffered Saline for drug release, we observed through the UV IVisible Absorption Spectrometer that the Ca-alginate generated by microfluidic chip could release different drug concentrations at the same time. Thus, the proposed microfluidic chip can be applied to producing microcapsules of different sizes and with different drug concentrations.