Slide immunoenzymatic assay (SIA)

Abstract

The use of antibodies as molecular probes for microbes and their antigens has a long tradition [19,23,24]. Poly- and monoclonal antibody probes have been used for microbial identification, characterization, classification, quantification, and manipulation for many years. The development of the enzyme-linked immunosorbent assay (ELISA) [8] has made the use of antibody probes in microbiology and microbial ecology popular and rewarding. The quantitative slide immunoenzymatic assay (SIA) [6] is a miniature ELISA with specific advantages and applications. SIA is simple, sensitive, and versatile [2,3,18], provides reproducible results, and can be automated, (Fig.1) [2,4]. SIA technology can be used for a variety of purposes [1,2,9,18,22–24]. These include identification and quantification of microbes in axenic cultures, in mixed cultures, and in complex microbial communities [4,6,7,14–16,24]. For these purposes, SIA can be used alone or in combination with immunofluorescence and other techniques [14]. SIA allows also detection and quantification of soluble and micro-particulate antigens secreted or released by microbes (microbial footprints as it were) into the culture medium, or into the environment (water and soil, for example) [2–4,6,7,23]. More recently, SIA technology has been adapted for molecular biology, to detect bacteria by nucleic-acid hybridization [5].