A ‘microfluidic Pinball’ for Continuous Generation of Layer-by-layer Polyelectrolyte Microcapsules

We present a novel approach for Layer-by-Layer (LbL) polyelectrolyte deposition in a “microfluidic pinball” device. Polyelectrolyte multilayers (PEMs) were coated on oil droplets by guiding them through parallel laminar streams of alternatively charged polyelectrolytes. Conventional LbL process is a time consuming and laborious process [1]. Past microfluidics based LbL approaches add operational and interfacial complexities with each deposited layer. Our microfluidic pinball approach utilizes a row of micropillars within a microfluidic channel to guide droplets while maintaining a fixed number of interface components. Uniform sized droplets were generated and six layers of PEMs were deposited, more than any existing technology [2-4].