Parylene coated poly(dimethylsiloxane) microfluidic channel for nonpolar solvent based nanocrystals growth

Poly(dimethylsiloxane) (PDMS), a transparent elastomeric polymer, has been widely used in the microfluidic field. However, applications of microfluidic device fabricated in PDMS have been limited to a bioanalysis based on water rather than nonpolar solvents because PDMS swells by absorbing the solvents. In case of inorganic nanocrystals growth into a superlattice structure, a PDMS microfluidic device can be used as long as a solvent-resistant capillary is inserted and assembled with the PDMS device for the growth of nanocrystals localized in nanoliter droplets. To solve the PDMS swelling problem and additional assembly process, we propose that a parylene film coated inside PDMS channel can serve as an effective barrier to the chemical solvents and prevent swelling. We found that a parylene coated PDMS microfluidic channel has a potential for the droplet based nanocrystals growth.