Formation of Polymeric Hollow Microcapsules and Microlenses Using Gas-in-Organic-in-Water Droplets

Abstract

This paper presents methods for the formation of hollow microcapsules and microlenses using multiphase microdroplets. Microdroplets, which consist of a gas core and an organic phase shell, were generated at a single junction on a silicon device without surface treatment of the fluidic channels. Droplet, core and shell dimensions were controlled by varying the flow rates of each phase. When the organic solvent was released from the organic phase shell, the environmental conditions changed the shape of the solidified polymer shell to either a hollow capsule or a microlens. A uniform solvent release process produced polymeric capsules with nanoliter gas core volumes and a membrane thickness of approximately 3 μm. Alternatively physical rearrangement of the core and shell allowed for the formation of polymeric microlenses. On-demand formation of the polymer lenses in wells and through-holes polydimethylsiloxane (PDMS) structures was achieved. Optical properties of the lenses were controlled by changing the dimension of these structures. OPEN ACCESSMicromachines 2015, 6 623

Microfluidics for core–shell drug carrier particles – a review

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Multiphase microfluidic synthesis of micro- and nanostructures for pharmaceutical applications

“…The core allows the encapsulation of various cargoes, ranging from drugs (Li et al, 2015;Liu et al, 2014;Vasiliauskas et al, 2015;Yang et al, 2009;Yang et al, 2014), proteins (Pessi et al, 2014;Yeh et al, 2011;Zhang et al, 2013), vitamins Yeh et al, 2013), cells (Ferreira et al, 2013;Kim and Kang, 2014;Mendes et al, 2012) to imaging agents (Abbaspourrad et al, 2013a;Abbaspourrad et al, 2013b;Gokmen et al, 2009) and magnetic nanoparticles (Ge et al, 2014;Liao and Su, 2010;Yang et al, 2009). Also, microcapsules with gas filled in the core have attracted interests (Abbaspourrad et al, 2013c;Yoon et al, 2015) especially for acoustic imaging as they are more echogenic than liquid-filled microcapsules. The shells of microcapsules, on the other hand, function as protective barriers for the encapsulated cargo, and its compositions and synthesis conditions determine the physical (e.g., mechanical strength, shell thickness, and diffusivity) and chemical (e.g., biocompatibility, biodegradability, and functionality) properties of the resultant microcapsules.…”

Continuous synthesis of BaFe2O4 and BaFe12O19 nanoparticles in a droplet microreactor for efficient detection of antihistamine drugs in oral fluid using surface-assisted laser desorption/ionization mass spectrometry

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