Overview of the TAC-BIO detector

Abstract

Ultra Violet (UV) induced fluorescence remains a core technique for the real time detection of biological aerosols. With this approach, the detection of an aerosolized biological event is based on the fluorescent and scattering signals observed from biological particles when exposed to one or more UV sources. In 2004, the Edgewood Chemical Biological Center (ECBC) initiated an effort to develop a low cost, small, lightweight, low power biological agent detector, identified as the TAC-BIO, based on this principle. Unlike previous laser based detectors, this program has capitalized on Semiconductor UV Optical Sources (SUVOS) being developed by the Defense Advanced Research Projects Agency (DARPA). Compared to the existing UV lasers, these SUVOS devices and their commercial counter-parts offered a means of achieving small, low cost, low power UV excitation sources. A general design philosophy of incorporating these devices with other low cost components has allowed ECBC to develop a detector that provides a credible degree of performance while maintaining the target size weight and power attributes. This paper presents an overview of the TAC-BIO and some of the findings to date.

Real-time sensing of bioaerosols: Review and current perspectives

“…In earlier systems, excitation was generally performed by relatively high-powered lasers. More recently, the use of smaller diode-pumped lasers, flash lamps, and light-emitting-diodes (LEDs) as light sources has greatly reduced the system size, weight, and power consumption (Cabalo et al 2008;Davitt et al 2005;Pan et al 2003a). Fluorescence spectra are also measured by several additional instrument types discussed below, but these are not presented in this section because they also rely heavily on other optical information for particle characterization.…”

Experimental Studies on the Classification of Airborne Particles Based on Their Optical Properties

“…The fluorescence signal originates from amino acids such as tryptophan, tyrosine, and riboflavin as well as enzymes . However, the fluorescence signals are 1000 times weaker than the scattered light and the fluorescence quantum efficiency (QE) of these materials is approximately 15% . For achieving high performance of LIF for monitoring bioaerosol, it is essential to use a high‐efficiency photodetector, an optical chamber, and a high‐powered ultraviolet light source due to the low fluorescence QE.…”

LIF bio-aerosol threat triggers: then and now

“…In operation it consumes approximately 6 watts of electrical power. The instrument is reported 45 to have reasonable ROC curve (see Section 2.9 below) performance at approximately 100 agent containing particles per liter of air (ACPLA) for standard Bacillus globigii challenges with particle sizes down to about 3 μm in diameter.…”