HIGHLY PARALLEL AND SENSITIVE HOLOGRAPHIC PLANAR WAVE-GUIDES FOR FLUOROIMMUNOASSAY

IMMUNOASSAY HAS PROVEN TO BE THE MOST SELECTIVE METHOD FOR DETECTION AND IDENTIFICATION OF BIOLOGICAL AGENTS. OPTICAL FLUOROIMMUNOASSAY (FIA), WITH SINGLE PHOTON COUNTING CAPABILITY, IS SUPPOSED TO BE THE MOST SENSITIVE TECHNIQUE. UNFORTUNATELY, DUE TO THE HIGH AUTOFLUORESCENT BACKGROUND FROM BULK SAMPLES, THE SENSITIVITY OF FIA IS OFTEN REDUCED. RESEARCHERS ARE DEVELOPING A COMPACT, HIGHLY SENSITIVE (0.1 PICOMOLE/ML) NEAR-REAL TIME (10 SECONDS) BIOLOGICAL INSTRUMENT BASED ON OPTICAL EVANESCENT WAVE DETECTION. THE SCOPE AND VERSATILITY OF THIS METHOD IS ENHANCED BY COMBINING THE PRINCIPLES OF FLUOROIMMUNOASSAY AND HOLOGRAPHIC PLANAR WAVEGUIDE TECHNOLOGY. APPLICATION OF TRANSPARENT MOTH EYE STRUCTURE INCREASES THE SURFACE AREA OF THE WAVEWUIDE, WHICH IS THE SENSING AREA OF THE DEVICE. THIS INCREASE IN SURFACE AREA ENHANCES DEVICE SENSITIVITY BY TWO ORDERS OF MAGNITUDE OVER FIBER OPTIC SENSORS. THE ADVANTAGES OF THE SYSTEM ARE THAT IT INVOLVES NO WASH, NO ANALYTE SEPARATION, NO AUTOFLUORESCENCE, AND IT CAN BE SIMULTANEOUSLY USED TO DETECT MULTIPLE ANALYTES. THE RESULTING DEVICE IS ROBUST, EASY TO USE, LOW COST, AND HAS LOW MAINTENANCE AND CALIBRATION REQUIREMENTS.