Well-designed microcapsules fabricated using droplet-based microfluidic technique for controlled drug release

Microfluidics is an emerging technology for synthesis of drug-loaded micro- and nano capsules for targeted delivery and controlled release, which has extensive applications in tumor therapy and pharmacological study in healthcare. A number of polydimethylsiloxane (PDMS) microfluidic devices have been developed and widely used, while PDMS based microstructure device does not support long-term stability and repeated use, moreover it requires special facilities for fabrication and plasma bonding. Therefore in our study, a non-PDMS tube-in-tube glass-capillary micro-device was fabricated and successfully used for generation of drug-loaded microcapsules with different structures and sizes. Compared with the PDMS and other conventional microfluidic devices, the glass-capillary microfluidic device has many advantages, including simplicity of fabrication, low cost, high throughput, reliability of generating droplets with uniform size and morphology, as well as ease of profound cleaning by rinsing with acid solution, and as a result, the availability for reuse. Furthermore, the size distribution and morphology dependent drug release mechanism for drug-loaded microcapsules was also studied in our work, providing significant guidelines for producing suitable microcapsules for the specific applications. By understanding the release kinetics, it can be possible to design and fabricate drug delivery micelles for the target applications, and regulate the release of drugs to satisfy the applications with required drug release profile. (C) 2017 Elsevier B.V. All rights reserved.