Gas chromatography is a technology that permits detection, classification and quantification of gas and vapor mixtures, showing wide application in environmental monitoring, military surveillance, and healthcare diagnostics. Miniaturization of the gas chromatograph to a portable platform would bring significant benefits in terms of speed, sensitivity, and cost. Such a micro gas chromatograph (uGC) would open many new sensing applications that cannot be addressed by existing instruments. This thesis seeks to overcome the challenges and limitations in instrumentation circuits for a uGC detector utilizing thiolate-monolayer-protected gold nanoparticles (MPN) chemiresistor (CR) arrays. Two approaches for CR array instrumentation were explored. First, a CMOS instrumentation circuit using DC techniques was designed and tested. The 8-channel DC chip achieves a resolution better than 125ppm over a very wide baseline resistance range and 120dB dynamic range. Second, an AC instrumentation circuit was developed to overcome the noise limitations inherent to the DC circuit. In addition, a methodology for integrating CR arrays directly onto the surface of the instrumentation chip was studied and implemented to further miniaturize the uGC and maximize resolution. The results of this research lay a solid foundation for future realization of high sensitivity uGCs.
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