Manufacturing size-controlled gelatin microparticles using a microfluidic chip

This study is to prepare monodisperse gelatin microparticles using a microfluidic chip. We have demonstrated that one can control the size of gelatin microparticles from 100 μm to 400 μm in diameter (with a variation less than 10%) by altering the relative sheath/sample flow rate ratio. The proposed microfluidic chip is capable of generating relatively uniform micro-droplets and has the advantages of actively controlling the droplet diameter, and having a simple and low cost process, with a high throughput. Experimental data show that when given a steady continuous phase (oil flow), the emulsion size increases with the increase in average velocity of the dispersed phase flow (sample flow). In addition, the size distribution of the resulting chitosan microspheres is narrow (about Polyindex = 1) which is suitable to provide the optimal release rate in the administration of controlled release drugs.