Microfluidics assisted synthesis of well-defined spherical polymeric microcapsules and their utilization as potential encapsulants

Abstract

In this article, the development of a novel technique to fabricate spherical polymeric microcapsules by utilizing microfluidic technology is presented. Atom transfer radical polymerization (ATRP) was employed to synthesize well-defined amphiphilic block copolymers. An organic polymer solution was constrained to adopt the spherical droplets in a continuous water phase at a T-junction microchannel, and the generation of the droplets was studied quantitatively. The flow conditions of two immiscible solutions were adjusted for the successful generation of the polymer droplets. The morphology of the microcapsules was examined. The efficiency of these polymer microcapsules as containers for the storage and controlled release of loaded molecules was evaluated by encapsulating the microcapsules with Congo-red dye and investigating the release performance using temperature controlled UV-VIS spectroscopy.

Fast Built and Designed Microdevices for Early‐Stage Liquid‐Liquid System Studies

“…Regular flows are obtained with a simple crossjunction [7]. The T-junction is also used to form droplets [8].…”

Monodispersed polygonal water droplets in microchannel

“…While there are several geometries 26 that have been used in the past to create droplets in microfluidic experiments, there are two designs that most commonly used, the T channel [27][28][29] and the Cross Channel [30][31][32] .…”

Microfluidic Synthesis of Reversibly Swelling Porous Polymeric Microcapsules with Controlled Morphology

“…Recently, we reported a method for producing uniform polymeric microcapsules using a flow-through droplet-based supramolecular self-assembly of the block copolymer in a crossed microchannel. [14] The self-organization of a suitable amphiphilic polymer in the dispersed phase and the hydrodynamic instability arising in the channel between the dispersed and continuous phases were effectively combined for the formation of uniform droplets, which leads to well-defined microcapsules. The molecular self-assembling behavior of amphiphilic block copolymers generating potential nano-structures has been investigated over the past few decades and continues to be a hot area of research due to their wide applications in various fields.…”

“…We performed detailed studies regarding this surface morphology by breaking the capsules and investigating the nature of its inner cavity. The surface of the capsule was partially removed by using oxygen plasma ashing [14] and this reveals the inner hollow characteristics and cavities of the capsules. The solvents chosen for generating droplets in the channel offers selective solubility for each block of the polymer-peptide molecule and this forces them to align in such a way that the PS block goes to the interior and PGA block line-up on the surface giving microcapsules with a hydrophobic cavity and hydrophilic surface.…”