Miniaturized and integrated chemical sensors: new fabrication platforms for biological, clinical and environmental applications

Abstract

Analytical chemistry techniques and technologies have rapidly emerged in the last years, but the cost and logistics for the samples collection at meaningful spatial scales and further analysis does not make their development and spread straightforward. Such problems can be better addressed by the fabrication of devices that operate autonomously at or near the sampling site, reducing the risks of error and contamination associated with manual sample acquisition, storage, and transport. This direct-reading chemical sensor operates by detecting and responding in a fast way to the presence or amount of an analyte at some interface between the sensor and the sample matrix. Those systems are capable of handling volumes on the microliter level and performing assays at short times, hence the miniaturization offers a suitable platform for portability and automation. Based on selected parameters, devices can be fabricated for analog signal gathering, processing, logging and remote presentation of data. Taking into account the above-mentioned, this research project aims at designing and developing integrated systems for real time monitoring of some target compounds at sites of environmental, health and biological relevance. The proposed devices will consist of several miniaturized electrochemical and optical sensors and emphasis will be given on apparatuses that can be easily implemented and possess reliable and long-time operation, as well as with wearable application. To achieve high selectivity toward the desired analytes, new platforms will be designed by using novel materials. In the absence of favorable selectivity, different strategies will be employed such as mathematical approaches (chemometric analysis) or the separation of the analyte from the sample matrix by using microfluidic devices. The developed sensors will have to satisfy analytical requirements (e.g. reduced drift response, resistance to surface fouling and high selectivity, accuracy and precision) as well as technological demands (mass-scale production at low cost, low power requirements and robust electronics). (AU)