The present invention provides for a system and method to detect low levels of the anthrax protective antigen (PA) exotoxin in biological fluids, wherein the system uses a metal-enhanced fluorescence (MEF)-PA assay in combination with microwave-accelerated PA protein surface absorption. Microwave irradiation rapidly accelerates PA deposition onto the surface adjacent to deposited metallic particles and significantly speeding up the MEF-PA assay and resulting in a total assay run time of less than 40 min with an analytical sensitivity of less than 1 pg/ml PA.
