Integrated microspectrometer for fluorescence based analysis in a microfluidic format

Abstract

We have demonstrated a monolithic integrated arrayed waveguide grating (AWG) microspectrometer microfluidic platform capable of fluorescence spectroscopic analysis. The microspectrometer in this proof of concept study has a small (1 cm × 1 cm) footprint and 8 output channels centred on different wavelengths. We show that the signals from the output channels detected on a camera chip can be used to recreate the complete fluorescence spectrum of an analyte. By making fluorescence measurements of (i) mixed quantum dot solutions, (ii) an organic fluorophore (Cy5) and (iii) the propidium iodide (PI)-DNA assay, we illustrate the unique advantages of the AWG platform for simultaneous, quantitative multiplex detection and its capability to detect small spectroscopic shifts. Although the current system is designed for fluorescence spectroscopic analysis, in principle, it can be implemented for other types of analysis, such as Raman spectroscopy. Fabricated using established semiconductor industry methods, this miniaturised platform holds great potential to create a handheld, low cost biosensor with versatile detection capability.