title: A compact CMOS biochip immunosensor towards the detection of a single bacteria.
abstract: Recent use of biological warfare (BW) agents has led to a growing interest in the rapid and sensitive detection of pathogens. Therefore, the development of field-usable detection devices for sensitive and selective detection of BW agents is an important issue. In this work, we report a portable biochip system based on complementary metal oxide semiconductor (CMOS) technology that has great potential as a device for single-bacteria detection. The possibility of single-bacteria detection is reported using an immunoassay coupled to laser-induced fluorescence (LIF) detection. Bacillus globigii spores, which are a surrogate species for B. anthracis spores, were used as the test sample. Enzymatic amplification following immunocomplex formation allowed remarkably sensitive detection of B. globigii spores, and could preclude a complicated optical and instrumental system usually required for high-sensitive detection. Atomic force microscopy (AFM) was employed to investigate whether B. globigii spores detected in the portable biochip system exist in single-cell or multicellular form. It was found that B. globigii spores mostly exist in multicellular form with a small minority of single-cell form. The results showed that the portable biochip system has great potential as a device for single-particle or possibly even single-organism detection.
authors.affiliation: Advanced Biomedical Science and Technology Group, Life Sciences Division, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831-6101, USA.
authors.forename: Joon Myong
authors.initials: JM
authors.lastname: Song
authors.forename: Mustafa
authors.initials: M
authors.lastname: Culha
authors.forename: Paul M
authors.initials: PM
authors.lastname: Kasili
authors.forename: Guy D
authors.initials: GD
authors.lastname: Griffin
authors.forename: Tuan
authors.initials: T
authors.lastname: Vo-Dinh
mesh_terms: D001407:Bacillus / Q000302:isolation & purification*; D001681:Biological Assay / Q000295:instrumentation* / Q000379:methods; D004797:Enzyme-Linked Immunosorbent Assay / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D016231:Fluorescence Polarization Immunoassay / Q000295:instrumentation* / Q000379:methods; D018613:Microscopy, Confocal / Q000295:instrumentation* / Q000379:methods; D008856:Microscopy, Fluorescence / Q000295:instrumentation* / Q000379:methods; D008904:Miniaturization / Q000379:methods; D012666:Semiconductors; D013170:Spores / Q000302:isolation & purification