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bioRxiv · 10.1101/2021.09.11.459879

Ultrafast, one-step, and microwave heating-based synthesis of DNA/RNA-AuNP conjugates

Huang, M.·Xiong, E.·Hu, M.·Yue, H.·Tian, T.·Zhu, D.·Zhou, X.
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Abstract

DNA/RNA-gold nanoparticle (DNA/RNA-AuNP) nanoprobes have been widely employed for nanobiotechnology applications. Here we discovered that both thiolated and non-thiolated DNA/RNA can be efficiently attached to AuNPs to achieve high-stable spherical nucleic acid (SNA) within minutes under a domestic microwave (MW)-assisted heating-dry circumstance. Further studies showed that for non-thiolated DNA/RNA the conjugation is poly (T/U) tag dependent. Spectroscopy, test strip hybridization, and loading counting experiments indicate that low-affinity poly (T/U) tag mediates the formation of a standing-up conformation, which is distributed in the outer layer of such a SNA structure. In further applications study, CRISPR/Cas9-sgRNA (135 bp), RNA from Nucleocapsid (N) gene of SARS-CoV-2 (1279 bp), and rolling circle amplification (RCA) DNA products (over 1000 bp) could be successfully attached on AuNPs, which overcomes the routine methods in long-chain nucleic acid-AuNP conjugation, exhibiting great promise in novel biosensing and nucleic acids delivery strategy. This novel heating-dry strategy has improved the traditional DNA/RNA-AuNP conjugation methods in simplicity, rapidity, cost, and universality.

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Huang, M., Xiong, E., Hu, M., Yue, H., Tian, T., Zhu, D., Zhou, X.. 2021-09-13. Ultrafast, one-step, and microwave heating-based synthesis of DNA/RNA-AuNP conjugates. https://doi.org/10.1101/2021.09.11.459879

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