Symposium 1997: Abstract for A Roda

Symposium 1997: Abstracts

Ultrasensitive Bio- and Chemiluminescent Imaging Using an Optical Microscope-Videocamera Luminograph: Appications in Biosciences and Drug Screening

A. Roda¹, P. Pasini¹, M. Musiani², M. Baraldini³
¹Dept. of Pharmaceutical Sciences,²Dept. of Clinical and Experimental Medicine and³Inst. of Chemical Sciences, University of Bologna, Bologna, Italy

A new chemiluminescent technique has been developed for ultrasensitive, quantitative analysis as well as visualization of the spatial distribution of biomolecules such as antigens, enzymes, antibodies, DNA probes, etc. in tissue or cells.

The system consists of a low-light imaging slow scan cooled CCD camera connected to an optical microscope, able to measure light at the single photon level and perform 3D image analysis of the subcellular distribution of the analyte. The concentration and the spatial distribution of enzymes, or enzyme-labeled biospecific reagents can be determined using appropriate chemiluminescent (CL) substrates. Analytes are also determined with coupled enzymatic reactions terminating in light emission.

Localization of enzymes such as acetylcholinesterase in brain tissue or oxygen free radicals in perfused whole liver organ can be used as predictive models for the screening of new drugs. Immunoenzymatic reactions for the detection of antigens (cytokeratin, interleukin 8) and in situ hybridization assays for the detection of viral DNAs (cytomegalovirus, parvovirus B19, human papillomavirus, herpes simplex virus) can be performed in cells and 5-8 mm thick tissue cryosections using different labeled antibodies or cDNA probes and CL substrates.

Given these characteristics, the system has many potential applications in molecular biology, biotechnological and pharmacological researches.