Fabrication of alginate nanoparticles using microfluidics, effect of flow rate on dispersity of particle diameters

Use of microfluidic flow regimes for large scale production of nanoparticles is important in the emerging fields of personalized and targeted drug delivery, fuel cell catalysis, LEDs, environmental remediation of spills, etc. Formulation of droplets with uniform diameters is a challenge which microfluidic devices have been reported to achieve. The overall goal of the present research is to scale capillary flows to a high throughput system using a patented fiber reactor.  The fluid mechanics of such environments has been studied as a model system in a microfluidic “T” junction apparatus for production of droplets of cross-linked alginate as well as immiscible oil-in-water emulsions. By tuning the relative volumetric flow rates of phases and/or the Capillary number we observed small changes in dispersed phase droplet diameter but also interestingly a ~30% reduction in the standard deviation of the diameter of droplets. The effect of use of surfactant and temperature will be discussed, and use of this information to produce micro- and nano-particles of calcium ion crosslinked sodium alginate for medical applications.