Handheld Biological Detection System

Colloidal suspensions of quantum dots (QD) offer a novel, inexpensive means of biological-warfare-agent (BWA) detection using compact lightweight systems that may be deployed in a variety of ways, including handheld biosensors. We propose here to design, fabricate and test portable, lightweight, user-friendly, low-logistical-load biosensors capable of automated and rapid BWA detection with high sensitivity and specificity for all classes of bioagents. The standard biofluidic techniques will be augmented with three specialized technologies: (a) QD technology, (b) optoelectronic techniques and (c) fluidic mixing techniques necessary to ensure adequate sampling. The successful technology already developed at UIC will be used to model and characterize experimentally changes in quantum-dot emission spectra as real-time indicators of molecular binding events. The highest priority will be given to detection based on fluorescent resonant energy transfer (FRET), using a dye paired with a QD within the Forster radius near two epitopes. In Phase I these changes will be characterized both experimentally and theoretically for a variety of simulants. Three detector modes will be demonstrated: (1) detection of molecules in the laboratory in colloidal suspensions of QD-engineered-surfactant complexes; (2) detection of analytes in handheld filter-paper-based assays; and (3) detection of analytes in a miniature microfluidic unit employing miniature LEDS and CCDs.