Miniature silicon electronic biological assay chip and applications for rapid battlefield diagnostics

摘要

Abstract: Assessing the medical condition of battlefieldpersonnel requires the development of rapid, portablebiological diagnostic assays for a wide variety ofantigens and enzymes. Ideally, such an assay would beinexpensive, small, and require no added reagents whilemaintaining the sensitivity and accuracy oflaboratory-based assays. In this work, amicroelectromechanical (MEMS) based biological assaysensor is presented which is expected to meet the aboverequirements. The sensor is a thin silicon membraneresonator (SMR) which registers a decrease in resonantfrequency when mass is adsorbed onto its surface. Bycoating the sensor surface with a monolayer ofantibody, for example, we have detected thecorresponding antigen with a detection resolution of0.25 ng/ml in phosphate buffer solution. Micromachiningtechniques are being used to integrate many (64elements on the first test chip) identical SMR sensorsinto a single silicon chip which would be capable ofsimultaneously performing a wide variety of biomedicalassays. The sensors require only a small printedcircuit board and 8V power supply to operate andprovide a readout. The presentation will describe theoperation of the SMR sensor, the fabrication of thesensor array, and initial test results usingcommercially available animal immunoglobulins inlaboratory-prepared test solutions. !15