Facile synthesis of magnetic agarose microfibers by directed self-assembly in W/O emulsions. (14th June 2016)

• Record Type: Journal Article
• Authors: Aldana, Samuel; Vereda, Fernando; Hidalgo-Alvarez, Roque; de Vicente, Juan
• Is Part Of: Polymer. Volume 93(2016)
• Page Start: 61
• Page End: 64
• Publication Date: 2016-06-14
• Subjects: Magnetic particles -- Microfibers -- Agarose -- Emulsions -- Ferrofluids; Polymers -- Periodicals; Polymerization -- Periodicals; Polymères -- Périodiques; Polymérisation -- Périodiques; 547.7
• DOI: 10.1016/j.polymer.2016.04.010
• Languages: English
• ISSNs: 0032-3861

Abstract

Abstract: We propose a new versatile approach for the fabrication of flexible magnetic microfibers having tunable size and mechanical properties. The methodology is based on the magnetic field-driven self-assembly of agarose-loaded kinetically unstable aqueous ferrofluid-in-oil emulsions. Agarose is dissolved at a temperature above its gelling point in an aqueous ferrofluid and the resulting suspension is then emulsified in oil and later exposed to a DC uniaxial magnetic field. Once the fibers have formed, the emulsion is quenched to force the gelification of the agarose, and a second addition of surfactant is carried out to prevent lateral aggregation of the fibers. Resulting fibers have diameters of the order of a few to tens of micrometers. A phase diagram is constructed and the influence of surfactant concentration and residence time under field in the synthesis is discussed. Graphical abstract: Highlights: Magnetic microfibers from self-assembly of unstable ferrofluid-in-oil emulsions. Aspect ratio controlled by the surfactant concentration and field strength. Elasticity of the microfibers controlled by the initial agarose concentration.