Microfluidic characterization of sustained solute release from porous supraparticles

We present a novel microfluidic technique for precise characterization of controlled release of solute from porous latex supraparticles in a laminar flow environment. Dye-infused supraparticles are fabricated via dry self-assembly method using droplet templates dispensed on superhydrophobic substrates. A water-soluble dye is used as a model compound, the release rate of which is measured colorimetrically. The sustained release rates of dye from supraparticles and dye pellets are quantified and compared to common diffusion/dissolution mass transfer models. The results illustrate the potential of microfluidics as a tool in monitoring controlled release process and the role of the uniformly porous supraparticle matrix for the prolonged continuous solute delivery.