bmdo technologies for biomedical applications - MDA Technology

VERSATILE TUNABLE FILTERFOR OPTICAL TASKS• Radiofrequency-based technologyfrom Ciencia helped improve a commonbiotech task.BMDO HISTORYCiencia, Inc. (East Hartford, CT), developed acousto-optic tunable filters(AOTFs) for use in target identification and surveillance systems. In 1992,Ciencia was awarded a BMDO SBIR Phase I contract to develop a dynamicallyadjustable amorphous-material-based AOTF to replace birefringentcrystals. Phase II funding was later awarded to pursue further developmentof the polymer AOTF for use in sensors. TheAOTF, originally meant to capture ultravioletMucosal dysplasia is aradiation, has proven to be a versatile toolwith a considerable impact in biomedicalprecancerous conditionand biotechnology areas. For example,that occurs in theCiencia is developing a prototype AOTFbasedoptical probe that may help to pinpointcertain types of heart disease by detect-gastrointestinal tract,ing unstable plaque in the coronary arteries.mouth, pharynx, bladder,In addition, radiofrequency generationcervix, and lung. Cancers technology developed under a BMDO SBIRfor implementation of AOTFs is at the heartthat originate in these of the least expensive and most rapid fluorescencelifetime sensing system on theareas account for a market. The system, called LifeSense, ismanufactured and distributed by Orielquarter million deaths perInstruments (Stratford, CT).year in the United States. HOW IT WORKSAcousto-optic devices use ultrasound toalter the refractive index of an optical medium,typically a crystal. Ciencia developed an AOTF based on an organicamorphous material rather than crystals. Amorphous materials are easierand cheaper to make than crystals, allow for uniformity and quality controlduring manufacturing, and permit independent control of bandpassand bandwidth.36By the application of mechanical stress or electric fields, Ciencia’s amorphousmedium can be induced to exhibit birefringence, a type of refractionin which the speed of light through the material depends on directionas well as the light’s frequency. Birefringence allows the AOTF to separatelight into different colors. Unlike an ordinary monochromator, the AOTFcan be tuned electronically, so it has no moving parts. In addition to beingtunable, the polymeric device can produce spectrally resolved images.MEDICAL SIGNIFICANCEOptical Signatures. Recent studies suggest that the chemical compositionof arterial plaque can indicate whether a person is likely to develop a bloodclot. Ciencia’s Raman-spectroscopy-based optical probe, coupled with theChapter 2 - Observation TechnologiesSection B - AnalysisBMDO Technologies for Biomedical Applications