Study On Resonance Light Scattering Soectroscopy Analysic Of Nucleic Acids By Using TiO₂ Nanoparticles As A Probe

The quantitative analysis of nucleic acids plays a very important role in life science. It is extensively used in biochemistry, molecular biology and medical diagnostics. In this dissertation, a new method of Resonance Light Scattering(RLS) spectroscopy analysis for nucleic acids was established based on the interaction between nucleic acids and TiO₂ nano-particles.About 2.0nm TiO₂ nano-particles were prepared according to the previous literature. When the nano-particles combine with nucleic acids by electrostatic forces, its resonance light scattering intensity is enhanced strongly with a maximum wavelength located at 300nm. Under the optimal conditions, the enhanced RLS intensity is well proportional to the concentration of nucleic acids in the range of 0.01-0.3μg/ml for calf thymus DNA, 0.01⁰.2μg/ml for fish sperm DNA and yeast RNA, respectively. The detection limit(3σ) are 4.0ng/ml for calf thymus DNA, 2.9ng/ml for fish sperm DNA and 2.7ng/ml for yeast RNA, respectively. Almost no interference can be observed from proteins and most of the metal ions. The method has been used for the determination of nucleic acids in synthetic samples with satisfactory results.