Fig. 2.
(a) Design of the polymer-based microfluidic chip with integrated fiber optics for delivering excitation light to the chip and collecting the resulting emission. The fibers were placed in guide channels embossed into the chip to allow exact placement during chip assembly and were oriented at 90° with respect to each other. The chip also contained a backside heater to control the temperature for hybridization-based assays. (b) Fluorescence image of the field-of-view of the excitation and emission fibers showing the intersection of the optical paths, which defined the probe volume that was determined to be 98 pL. The chip was filled with Alexa Fluor 660 dye to generate the necessary image.