Fabricated Opto-Fluidic Microsystem
The integration of optics and fluidics opens new opportunities for the creation of compact biomedical diagnostic microsystems. The main motivation behind miniaturization and integration of different optical and fluidic components is the increase in capability. The goal of a future micro-total-analysis-system (µTASs) is to integrate the capabilities of entire laboratories onto a compact handheld microchip.
Top view of PDMS channel and VCSELs
In this project we work on the compact integration of near-infrared vertical-cavity surface-emitting lasers (VCSELs) with a microfluidic chip. VCSEL arrays are integrated into a silicon platform, and reversibly sealed against a microfluidic network of channels. The resulting reusable microanalysis system enables direct optical sensing of fluidic channels while keeping fluids and optoelectronic components isolated from each other.
Image of measurement set-up showing optofluidic network and external photodetector
Absorption and fluorescence measurements using different concentrations of an infrared absorbing dye (IR-800) are performed. The infrared dye is dissolved in methanol to yield an absorption maximum at 778 nm. Various dye solutions are pushed through the microfluidic channels over the integrated 780-nm VCSELs. The fluorescent light is measured using an external photodetector. Multiple scans of the integrated VCSELs are taken to determine the sensitivity of the system.
Fluorescence characteristics for IR dye IR-800