Pin-printed chemical sensor arrays for simultaneous multianalyte quantification

A new approach to rapidly produce micrometer-scale sensor elements into reusable multianalyte chemical sensor arrays is demonstrated. By using pin printing technology in concert with sol-gel processing methods, we form discrete xerogel-based microsensors on a planar substrate. We illustrate the new approach by forming discrete O₂- and pH-reponsive sensing elements into arrays that allow one to simultaneously determine O₂ and pH in aqueous samples. The pin printing method allows one to prepare sensor elements that are on the order of 100 μm thick, at a rate of approximately one sensor element per second with a single pin. Within a given calibrated array, the sensor element-to sensor element response is reproducible to within 5%, the sensor element short- and long-term reproducibilities are 3 and 6%, respectively, and the array-to-array response reproducibility is 11%. These results demonstrate the potential of this methodology for rapidly forming ensembles of reusable sensor arrays for simultaneous multianalyte detection.