A hybrid microdevice with a thin PDMS membrane on the detection window for UV absorbance detection

We exploited a PDMS‐quartz hybrid microchip with a thin PDMS membrane on the concave detection window for UV absorbance detection. The thickness of the PDMS membrane is about 100 μm, with high UV transmittance. As compared to a PDMS‐quartz hybrid chip with a common detection window, the proposed one exhibited over an one order of magnitude sensitivity enhancement, and an about two orders of magnitude S/N increase for gastrodin ( p ‐hydroxymethylphenyl‐β‐ D ‐glucopyranoside). In addition, the limit of the detection wavelength has been extended from 240 to 210 nm, which is otherwise impossible for a traditional PDMS‐quartz hybrid microchip. This kind of microchip has the potential for a large range of applications in an integrated microfluidic system with UV detection.