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Updated: Aug 29, 2026

Spectroscopic Super-resolution Imaging of DNA Molecules using Intrinsic Contrast
Published on: March 6, 2026
Determination of DNA by Rayleigh light scattering enhancement of molecular "light switches"
Fang Chen1, Jianping Huang, Xinping Ai
1College of Chemistry & Molecular Sciences, Wuhan University, Wuhan 430072, PR China.
Abstract:
Base on the enhancement of Rayleigh light scattering signals of molecular "light switches" by DNA under acidic condition, a sensitive and convenient method for DNA determination was proposed. The experiments indicated that, under optimum conditions, good linear relationships were obtained between the Rayleigh light scattering intensity and the concentration of nucleic acids. The detect limits of calf thymus DNA (ctDNA) were 13.0 ng ml(-1), 4.2 ng ml(-1), 51.5 ng ml(-1) and 3.0 ng ml(-1) with four "light switches", respectively. Plasmid DNA extracted from Bacillus subtilis were determined by the proposed method with satisfactory results, and the recovery rates of calf thymus DNA were in the range of 94.6-110.7%.
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