Drawing Silicone Fiber Optics for Flexible Biosensors

Abstract

In vivo fiber optic biosensing is limited by mechanical and chemical characteristics: fiber flexibility, permeability, biocompatibility and analyte sensitivity. We have developed a method for gravity-drawing silicone PDMS filaments with diameters on the order of a hundred micrometers, which directly address these limitations. We demonstrate that PDMS filaments are multimode fiber optics with reasonable losses for device applications (∼1.3dB/cm). Their flexibility relative to their glass and acrylic counterparts makes them attractive as biosensors, with a measured Young's modulus that is three to four orders of magnitude less stiff than glass/acrylic fiber optics. Additionally, a silicone fiber's transmission may be tuned to be solvent or gas sensitive, suggesting low-cost applications as both biological and environmental sensors. Kiessling, R., Rubin, S.J., Zehner, J., Barraugh, C., Snell, K., Fukushima, C., Mulligan, M., Keckley, M., Bosshardt, A., Cook, W. and Sanii, B., 2017. Gravity-Drawn Silicone Filaments: Production, Characterization, and Wormlike Chain Dynamics. ACS applied materials & interfaces, 9(46), pp.39916-39920. Snell, K., Lopez, I., Louie, B., Kiessling, R. and Sanii, B., 2019. Drawing and Hydrophobicity-patterning Long Polydimethylsiloxane Silicone Filaments. JoVE (Journal of Visualized Experiments), (143), p.e58826.