摘要
      这项研究使用银纳米粒子从水中去除携带抗生素抗性基因的DNA。合成了三种不同摩尔浓度的银纳米颗粒，分别表示为BD1（0.1M）、BD2（0.5M）和BD3（1.0M）作为吸附剂，并在分批吸附系统中对其进行评估，以从模拟水溶液中去除携带抗生素抗性基因的细菌DNA。通过使用傅里叶变换红外光谱（FTIR）、扫描电子显微镜（SEM）结合能量色散x射线光谱（EDX）和x射线衍射光谱（XRD）的表征技术证实了吸附剂的真实性，表明这些AgNP的合成是成功的。涉及合成材料上不同操作条件的吸附研究表明，pH影响DNA的去除，在酸性pH下观察到去除效率提高（BD1、BD2和BD3的去除率分别为50.26-87.61%、65.80-87.79%和69.23-87.92%）。BD1、BD2和BD3在180、195和225分钟后达到最大吸附平衡。等温线研究表明，与Freundlich模型相比，Langmuir模型是最佳拟合，BD1、BD2和BD3的相关系数最高，卡方（X2）分别为R2=0.7625和X2=0.11242，R2=0.96049和X2=0.24003，R2=0.85108和X2=1.00914。吸附过程的动力学研究表明，细菌DNA在AgNPs上的吸附服从拟二级吸附，R2值最高（从0.90到0.98）。同样，竞争离子（阳离子和阴离子）也影响了本研究的吸附能力。因此，本研究得出结论，AgNPs在去除水中携带ARGs的细菌DNA方面表现出了有效性，并将成为应对水中ARGs威胁的绝佳选择。
Abstract
This study employed silver nanoparticles to remove DNA conveying antibiotic resistance genes from water. Three different molar concentrations of silver nanoparticles represented as BD1 (0.1 M), BD2 (0.5 M), and BD3 (1.0 M) were synthesized as adsorbents and evaluated in a batch adsorption system for the removal of bacteria DNA conveying antibiotic resistance genes from simulated aqueous solution. The authenticity of the adsorbents was confirmed by characterization techniques using Fourier transformed infrared spectroscopy (FTIR), scanning electron microscopy (SEM) coupled with energy-dispersive x-ray spectroscopy (EDX), and x-ray diffraction spectroscopy (XRD) indicated the successful synthesis of these AgNPs. Adsorption studies involving the different operating conditions on the synthesized materials showed that pH affects the removal of DNA with increased removal efficiency observed at acidic pH (removal percentage ranging from 50.26-87.61%, 65.80-87.79%, and 69.23-87.92% for BD1, BD2, and BD3 respectively). Maximum adsorption equilibrium was achieved after 180, 195, and 225 mins for BD1, BD2, and BD3. The isotherm study revealed that Langmuir model is the best fit compared to Freundlich model with highest correlation coefficient and reduced Chi-square (X2) of R2 = 0.97625 and X2 = 0.12142, R2 = 0.96049 and X2 = 0.24403, R2 = 0.85108 and reduced X2 = 1.00914 for BD1, BD2, and BD3 respectively. The kinetic study for the adsorption process indicates that the adsorption of bacteria DNA onto AgNPs obeyed pseudo-second-order with the highest R2 values (ranging from 0.90 to 0.98). Similarly, competing ions (cations and anions) influenced the adsorption capacity in this study. Therefore, this study concludes that AgNPs demonstrated effectiveness in removing bacteria DNA-conveying ARGs from water and will serve as an excellent option to tackle the menace of ARGs in water.

https://www.sciencedirect.com/science/article/pii/S2352952022000238