Organic Photodetectors for Chemiluminescence Assays

One of the preferred methods for analyte detection in microfiuidic devices is based on the phenomenon of chemiluminescence (CL), which offers a simple but sensitive means of monitoring low level analyte concentrations [26]. CL reactions typically involve the formation of a metastable reaction intermediate or product in an electronically excited state, which subsequently relaxes to the ground state with the emission of a photon. CL is particularly attractive for portable microfiuidic assays, because the CL reaction acts as an internal light-source, thereby lowering instrumental requirements and significantly reducing power consumption and background interference compared to fluorescence assays. CL-based systems have been successfully applied to on-chip electrophoretic separation of metal ions, immunoassays, and enzyme assays [27], and consequently there is considerable interest in 

To improve the limit-of-detection, we replaced the 16 mm vacuum deposited CuPc/Cgg bilayer devices with 1 mm solution-processed polymer devices based on 1 1 blends by weight of poly(3-hexylthiophene) [P3HT] and [6, 6]-phenyl-C61-butyric acid-methylester [PCBM] - a soluble derivative of Ceo- The P3HT PCBM devices fabricated in our laboratory typically have very low short-circuit dark current densities of 10 mA cm , and are consequently a good choice for high sensitivity detection [21]. The 

To initiate the CL reaction, the dye/catalyst mixture and the H2O2 were pumped hydrodynamically into inlets 1 and 2, respectively and, after waiting 

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