Mixed Electronic and Optical Computing Platforms for Portable Surface Plasmon Resonance Sensors

Arizona State University, Scottsdale AZ

Investigators

Abstract

0086947 Booksh The environmental sensing goal of this project is to develop and demonstrate new engineering capabilities associated with optical computational methods for improving the design and performance of optical sensors for convenient, user-friendly, and field-portable environmental analyses. Optical computational methods and novel systems integration approaches promise reduction in power requirements for field portable sensors, simplification of electronics and optical train of field portable sensors, optimization of signal collection and processing for field portable sensors, and adaptation to changing calibration models by updating the programmable memory in the sensor controller. Thus, compared to traditional sensors that rely in discrete digitization of optical signals, smaller, lighter, and less power-hungry sensors with superior detection limits are to be developed using these new engineering technologies. The proposed novel optical computational methods will be incorporated in the design and construction of hand held surface plasmon resonance (SPR) sensors for determination of a range of environmental pollutants at superior detection limits and sensitivities. In Phase 1, application of the sensor will be limited to quantitation of polycyclic aromatic hydrocarbons (PAHs) in ground water. PAHs are carcinogenic EPA priority pollutants that largely enter the environment through fuel and oil spills or as a byproduct of incomplete combustion. In Phase 2, this sensor will be expanded to a massively parallel array of SPR sensors designed for multi-analyte detection. The scope of target analytes will be expanded to other (EPA) priority pollutants. One key area of progress to the sensors designed for both Phase 1 and Phase 2, will be the increasing ability of the system to account for environmental changes that affect the SPR spectrum. In Phase 1 of the proposed research, these optical computations will be integrated into a novel, fiber optic, surface plasmon resonance sensor design. The goals of Phase 1 are to demonstrate the improvements in sensitivity, power, space, and signal-to-noise ratio achievable with integrated optical computation in the SPR sensor, to improve system concentration sensitivity in isolated but integrated photodetectors, to demonstrate programmability for ease of calibration and referencing to environmental changes, and to increase greater than 12 hours of battery life capable of determining to +/- 1% PAH concentration down to ppb levels in a changing environment. The fiber optic SPR sensor will have two sensing areas: one responsive to the target analyte and any environmental changes, the other responsive to only environmental changes.