Fluorimetric bioprobe for genotoxicity based on DNA-Dye intercalation

Abstract

The potential of a nucleic acid-based optical bioprobe for environmental measurements and drug monitoring is described. The sensor employs long - wavelength intercalating fluorophores like TO-PRO-3 (TP3). Compounds that interact with the TP3-DNA complex are indirectly detected by a decrease in the fluorescence intensity. We found that the configuration and length of the DNA dramatically affected the intensity of the fluorescence emitted from the TP3-DNA complex. We have compared nucleic acids from different sources and optimized the system. In one proposed method, we attempt to combine broad-range detection with rapid and simple operation. A fiber-optic capillary fluorescence system was used to analyze toxic aromatic amines, antibiotics, and several kinds of antitumor drugs, using small amounts of sample, down to 10 μL, with sensitivity comparable to that of current electrochemical methods. The detection limit can be as low as a few ppb or submicromolar. This approach is useful for routine screening in environmental monitoring or for controlling cytotoxic drug administration. The ease of operation and the rapid response allow high-throughput screening. To enable sufficiently high sensitivity to detect substances that may be used for bioterrorism concentration enhancing methods such as SPE can be used for sample collection. © 2012 Springer Science+Business Media B.V.