This paper presents disposable protein analysis chips with single and multiple chambers - constructed from poly (dimethylsiloxane) (PDMS) and silicon. The chips are composed of a multilayer stack of PDMS layers that sandwich a silicon microchip. This inner silicon chip features an etched array of microcavities hosting agarose beads. The sample is introduced into the fluid network in the top PDMS layer where it is directed to the bead chamber. After reaction of the analyte with the probe beads, signal generated on the beads is captured with a CCD camera, digitally processed, and analyzed. An established bead-based fluorescent assay for C-reactive protein (CRP) was used here to characterize these hybrid chips. The detection limit of the single chamber protein chip was found to be 1ng/mL. Additionally, using the back pressure compensation method, the signals from each of the four-chamber chip were found to be within 10% of each other. Moreover, the fabrication of the multiple-chamber chip may increase throughput and multiplex assay capacity.
A Wireless Bio-MEMS Sensor for C-Reactive Protein Detection Based on Nanomechanics
