Park Daniel S-W, Young Brandon M, You Byoung H, Singh Varshni, Soper Steven A, Murphy Michael C
Center for BioModular Multiscale Systems for Precision Medicine, Department of Mechanical and Industrial Engineering, Louisiana State University, Baton Rouge, LA 70803, USA.
Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, NC, USA and is now with the Center for BioModular Multiscale Systems for Precision Medicine, at the University of Kansas, Lawrence, KS 66045.
J Microelectromech Syst. 2020 Aug;29(4):600-609. doi: 10.1109/jmems.2020.3004374. Epub 2020 Jul 2.
An improved, laser-induced fluorescence-based micro-optical biosensor was designed and fabricated, with cyclic olefin copolymer (COC) optical waveguides, a poly(methyl methacrylate) (PMMA) fluidic substrate with an array of microlenses, and a COC coupling prism integrated with the waveguide substrate or cover plate. The double-sided hot embossed fluidic substrate had sampling zone microchannels on the bottom and microlenses on the top. Dissolved COC injected into polydimethylsiloxane (PDMS) lost molds embedded the waveguides in the PMMA cover plate and formed the integrated coupling prism. The embedded COC waveguide was flycut down to 50 μm. The cover plate and shallow, 1:20 aspect ratio, microchannels were thermal fusion bonded using a pressure-assisted boiling point control system, without sagging. The large COC prism coupled better to the waveguide. The highest intensity evanescent excitation of the waveguide was obtained near the critical angle. The maximum signal-to-noise ratio (SNR) was 119 and the lowest detection limit was 7.34 × 10 mol at a SNR of 2 for a 100 μm wide by 50 μm deep waveguide. The microlenses highly focused the fluorescent radiation in the sampling zone. The microfabricated waveguide enables rapid, low-cost detection of fluorescent samples with high SNR, a low detection limit, and high sampling efficiency.
设计并制造了一种改进的基于激光诱导荧光的微光学生物传感器，它具有环烯烃共聚物（COC）光波导、带有微透镜阵列的聚甲基丙烯酸甲酯（PMMA）流体基板以及与波导基板或盖板集成的COC耦合棱镜。双面热压印流体基板底部有采样区微通道，顶部有微透镜。注入聚二甲基硅氧烷（PDMS）失模中的溶解COC将光波导嵌入PMMA盖板并形成集成耦合棱镜。将嵌入的COC光波导铣削至50μm。盖板和浅的、长宽比为1:20的微通道使用压力辅助沸点控制系统进行热压合，不会下垂。大的COC棱镜与光波导的耦合更好。在临界角附近获得了光波导的最高强度倏逝激发。对于100μm宽×50μm深的光波导，在信噪比为2时，最大信噪比（SNR）为119，最低检测限为7.34×10⁻⁹mol。微透镜将荧光辐射高度聚焦在采样区。这种微制造的光波导能够以高信噪比、低检测限和高采样效率快速、低成本地检测荧光样品。
