Confocal fluorescence spectral imaging technique and its applications to drug development

A spectral analysis that is widely used to study molecular interactions in solutions can be transferred to cellular and tissue levels and is a basis of a confocal spectral imaging (CSI) technique. The technique is a potent tool to deconvolve overlapping spectra of fluorophores in a specimen, to discriminate weak signals of fluorophores interfering with cellular autofluorescence and to study molecular interactions of drugs within living cells. The CSI technique measures a two-dimensional set of spectra with a three-dimensional spatial resolution from a tissue section or an intact living cell treated with a fluorescent drug and analyzes it in order to: identify and map molecular interactions of the drug; quantify accumulation, localization and retention of the drug in the specimen. Features of the CSI technique are illustrated with our data obtained in the course of development and studies of advanced agents for photodynamic and boron neutron-capture anticancer therapies.