Detecting γ-radiation damage of DNA-AuNPs assemblies using surface-enhanced Raman scattering

A novel approach for detecting radiation damage to radiosensitive genes was developed using surface-enhanced Raman scattering (SERS) technology. Radiosensitive gene fragments were modified with thiol groups and immobilized onto the surface of gold nanoparticles (AuNPs) to form single-stranded and double-stranded DNA through Au-S bonds. SERS was used to analyze the response of DNA-AuNPs assemblies to γ-rays and the local enhancement effect of AuNPs on this response to γ-radiation. The results showed that the 663 cm^-1 spectral peak of the double-stranded DNA-AuNPs assemblies varied with the dose range of γ-radiation (0 to ∼ 200 Gy). Similarly, the single-stranded DNA-AuNPs showed a good response to γ-radiation in the dose range of 0 ∼ 100 Gy, and the sensitivity of the DNA-AuNPs assembly noticeably increased with the increase in bound AuNPs. This positive correlation was due to the localized surface plasmon resonance of the AuNPs. The analysis of DNA-AuNPs assemblies using SERS scattering, could potentially be a novel method for the detection and measurement of ionizing radiation causing damage to genes. (authors)