title: Synthesis of Poly(N-isopropylacrylamide) Janus Microhydrogels for Anisotropic Thermo-responsiveness and Organophilic/Hydrophilic Loading Capability.
abstract: Janus microparticles are compartmentalized particles with differing molecular structures and/or functionality on each of their two sides. Because of this unique property, Janus microparticles have been recognized as a new class of materials, thereby attracting a great deal of attention from various research fields. The versatility of these microparticles has been exemplified through their uses as building blocks for self-assembly, electrically responsive actuators, emulsifiers for painting and cosmetics, and carriers for drug delivery. This study introduces a detailed protocol that explicitly describes a synthetic method for designing novel Janus microhydrogels composed of a single base material, poly(N-isopropylacrylamide) (PNIPAAm). Janus microdroplets are firstly generated via a hydrodynamic focusing microfluidic device (HFMD) based on the separation of a supersaturated aqueous NIPAAm monomer solution and subsequently polymerized through exposure to UV irradiation. The resulting Janus microhydrogels were found to be entirely composed of the same base material, featured an easily identifiable compartmentalized morphology, and exhibited anisotropic thermo-responsiveness and organophilic/hydrophilic loading capability. We believe that the proposed method introduces a novel hydrogel platform with the potential for advanced synthesis of multi-functional Janus microhydrogels.
authors.affiliation: Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH).
authors.forename: Kyoung Duck
authors.initials: KD
authors.lastname: Seo
authors.affiliation: Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH).
authors.forename: Andrew
authors.initials: A
authors.lastname: Choi
authors.affiliation: Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH); School of Interdisciplinary Bioscience and Bioengineering (I-Bio), Pohang University of Science and Technology (POSTECH).
authors.forename: Junsang
authors.initials: J
authors.lastname: Doh
authors.affiliation: Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH); smkds@postech.ac.kr.
authors.forename: Dong Sung
authors.initials: DS
authors.lastname: Kim
mesh_terms: D000180:Acrylic Resins / Q000138:chemical synthesis*; D016880:Anisotropy; D016503:Drug Delivery Systems; D020100:Hydrogels / Q000138:chemical synthesis*; D057927:Hydrophobic and Hydrophilic Interactions; D044085:Microfluidics / Q000379:methods*; D011108:Polymers / Q000138:chemical synthesis*; D013696:Temperature
chemical_list: D000180:Acrylic Resins; D020100:Hydrogels; D011108:Polymers; C052970:poly-N-isopropylacrylamide