On-chip polyelectrolyte coating onto magnetic droplets – towards continuous flow assembly of drug delivery capsules

Alorabi, Ali Q.; Tarn, Mark D.; Gómez-Pastora, Jenifer; Bringas, Eugenio; Ortiz, Inmaculada; Paunov, Vesselin N.; Pamme, Nicole

Abstract

Polyelectrolyte (PE) microcapsules for drug delivery are typically fabricated via layer-by-layer (LbL) deposition of PE layers of alternating charge on sacrificial template microparticles, which usually requires multiple incubation and washing steps that render the process repetitive and time-consuming. Here, ferrofluid droplets were explored for this purpose as an elegant alternative of templates that can be easily manipulated via an external magnetic field, and require only a simple microfluidic chip design and setup. Glass microfluidic devices featuring T-junctions or flow focusing junctions for the generation of oil-based ferrofluid droplets in an aqueous continuous phase were investigated. Droplet size was controlled by the microfluidic channel dimensions as well as the flow rates of the ferrofluid and aqueous phases. The generated droplets were stabilised by a surface active polymer, polyvinylpyrrolidone (PVP), and then guided into a chamber featuring alternating, co-laminar PE solutions and wash streams, and deflected across them by means of an external permanent magnet. The extent of droplet deflection was tailored by the flow rates, the concentration of magnetic nanoparticles in the droplets, and the magnetic field strength. PVP-coated ferrofluid droplets were deflected through solutions of polyelectrolyte and washing streams using several iterations of multilaminar flow designs. This culminated in an innovative

Citation

Alorabi, A. Q., Tarn, M. D., Gómez-Pastora, J., Bringas, E., Ortiz, I., Paunov, V. N., & Pamme, N. (2017). On-chip polyelectrolyte coating onto magnetic droplets – towards continuous flow assembly of drug delivery capsules. Lab on a chip, 17(22), 3785-3795. https://doi.org/10.1039/c7lc00918f

• Acceptance Date: Oct 2, 2017
• Online Publication Date: Oct 2, 2017
• Publication Date: Oct 21, 2017
• Deposit Date: Oct 9, 2017
• Publicly Available Date: Oct 3, 2018
• Journal: Lab on a chip
• Print ISSN: 1473-0197
• Electronic ISSN: 1473-0189
• Publisher: Royal Society of Chemistry
• Peer Reviewed: Peer Reviewed
• Volume: 17
• Issue: 22
• Pages: 3785-3795
• DOI: https://doi.org/10.1039/c7lc00918f
• Keywords: Biochemistry; Bioengineering; General Chemistry; Biomedical Engineering
• Public URL: https://hull-repository.worktribe.com/output/455588
• Publisher URL: http://pubs.rsc.org/en/content/articlelanding/2017/lc/c7lc00918f#!divAbstract