A fiber optic biosensor for fluorimetric detection of triple-helical DNA
| Autor: | Masad J. Damha, Ulrich J. Krull, Robert H. E. Hudson, Andre H. Uddin, Paul A. E. Piunno |
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| Jazyk: | angličtina |
| Rok vydání: | 1997 |
| Předmět: |
Analytical chemistry
Biosensing Techniques Biology Nucleic Acid Denaturation Nucleic acid thermodynamics chemistry.chemical_compound Ethidium Genetics Fiber Optic Technology A-DNA Optical Fibers Molecular Structure Oligonucleotide Temperature Nucleic Acid Hybridization DNA Fluorescence Intercalating Agents Biochemistry Relative fluorescence units chemistry Microscopy Fluorescence Oligodeoxyribonucleotides Nucleic Acid Renaturation Electrophoresis Polyacrylamide Gel Ethidium bromide Biosensor Research Article |
| Popis: | A fiber optic biosensor was used for the fluorimetric detection of T/AT triple-helical DNA formation. The surfaces of two sets of fused silica optical fibers were functionalized with hexaethylene oxide linkers from which decaadenylic acid oligonucleotides were grown in the 34 to 54 and 54 to 34 direction, respectively, using a DNA synthesizer. Fluorescence studies of hybridization showed unequivocal hybridization between oligomers immobilized on the fibers and complementary oligonucleotides from the solution phase, as detected by fluorescence from intercalated ethidium bromide. The complementary oligonucleotide, dT10, which was expected to Watson‐Crick hybridize upon cooling the system below the duplex melting temperature (Tm), provided a fluorescence intensity with a negative temperature coefficient. Upon further cooling, to the point where the pyrimidine motif T*AT triple-helix formation occurred, a fluorescence intensity change with a positive temperature coefficient was observed. The reverse-Hoogsteen T·AT triplex, which is known to form with branched nucleic acids, provided a corresponding decrease in fluorescence intensity with decreasing temperature. Full analytical signal evolution was attainable in minutes. |
| Databáze: | OpenAIRE |
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