Li Song, Tang Jing, Bai Yalong, Pu Chunmin, Liao Xiaoyan, Chen Lili
Department of Public Health Laboratory Sciences, College of Public Health, Hengyang Medical School, University of South China, 28 Changsheng West Road, Hengyang, 421001, Hunan, China.
Institute for Agri-Food Standards and Testing Technology, Shanghai Academy of Agricultural Sciences, 1000 Jinqi Road, Shanghai, 201403, China.
Mikrochim Acta. 2025 Sep 8;192(10):640. doi: 10.1007/s00604-025-07511-4.
We systematically evaluated the DNA adsorption and desorption efficiencies of several nanoparticles. Among them, titanium dioxide (TiO₂) nanoparticles (NPs), aluminum oxide (Al₂O₃) NPs, and zinc oxide (ZnO) NPs exhibited strong DNA-binding capacities under mild conditions. However, phosphate-mediated DNA displacement efficiencies varied considerably, with only TiO₂ NPs showing consistently superior performance. Further investigation into the DNA adsorption and desorption mechanisms of TiO₂ NPs led to the following key results: (1) TiO₂ NPs achieved over 98% DNA adsorption at room temperature, but efficient desorption required elevated temperatures; (2) phosphate-induced DNA displacement depended on the full exposure of phosphate groups, and short DNA fragments were insufficient to effectively compete with adsorbed DNA; (3) the adsorption mechanism of TiO₂ NPs involved multiple interactions, such as coordination and hydrogen bonding. The combination of strong coordination and weak ionic forces likely contributed to the high efficiency of phosphate-mediated desorption. Under optimized conditions, TiO₂ NPs demonstrated excellent separation efficiency for structurally complex DNA, with recovery rates of 56.92% for genomic DNA and 66.31% for plasmid DNA, notably higher than those of amino-modified silica-coated magnetic nanoparticles (ASMNPs; 38.66% and 33.59%). These results highlight the potential of TiO₂ NPs as a powerful tool for trace DNA isolation under mild, biocompatible conditions, with promising applications in nucleic acid separation and molecular diagnostics.
我们系统地评估了几种纳米颗粒的DNA吸附和解吸效率。其中，二氧化钛（TiO₂）纳米颗粒（NPs）、氧化铝（Al₂O₃） NPs和氧化锌（ZnO） NPs在温和条件下表现出较强的DNA结合能力。然而，磷酸盐介导的DNA置换效率差异很大，只有TiO₂ NPs始终表现出卓越的性能。对TiO₂ NPs的DNA吸附和解吸机制的进一步研究得出了以下关键结果：（1）TiO₂ NPs在室温下实现了超过98%的DNA吸附，但高效解吸需要升高温度；（2）磷酸盐诱导的DNA置换取决于磷酸基团的完全暴露，短DNA片段不足以有效竞争吸附的DNA；（3）TiO₂ NPs的吸附机制涉及多种相互作用，如配位和氢键。强配位和弱离子力的结合可能有助于磷酸盐介导的解吸的高效率。在优化条件下，TiO₂ NPs对结构复杂的DNA表现出优异的分离效率，基因组DNA的回收率为56.92%，质粒DNA的回收率为66.31%，明显高于氨基修饰的二氧化硅包覆磁性纳米颗粒（ASMNPs；38.66%和33.59%）。这些结果突出了TiO₂ NPs作为一种在温和、生物相容条件下用于痕量DNA分离的强大工具的潜力，在核酸分离和分子诊断方面具有广阔的应用前景。
