Swelling of poly-methylmethacrylate (PMMA) in weak solvents: water, ethanol and methanol was investigated by interferometry using a simple microfluidic sensor. A change of channel width by ±20 nm, comparable with the surface roughness of the polymer surface, is reliably detected and its temporal evolution was monitored in situ. Dynamics of polymer swelling over time periods from a few seconds to a few days were obtained. An optimized in-expensive microfluidic sensor design using hot embossing with gold sputtering is presented. Such a sensor can be used for high-fidelity adsorption-desorption interferometric sensing and its cost can be optimized for a single use.
Proceedings of the International Quantum Electronics Conference and Conference on Lasers and Electro-Optics (Pacific Rim IQEC/CLEO 2011) incorporating the Australasian Conference on Optics, Lasers and Spectroscopy (ACOLS) and the Australian Conference on Optical Fibre Technology (ACOFT), Sydney, New South Wales, Australia, 28 August - 01 September 2011,