Misra Nilanjal, Rawat Swarnima, Shelkar Shubhangi A, Ghosh Ayan, Kumar Sanjay, Kumar Virendra
Radiation Technology Development Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085, India.
Homi Bhabha National Institute, Anushaktinagar, Mumbai, 400085, India.
Discov Nano. 2025 Jun 16;20(1):95. doi: 10.1186/s11671-025-04275-x.
We describe the Co-Gamma radiolytic synthesis of stable poly(bis[2-(methacryloyloxy)ethyl] phosphate) (PB2MEP) -decorated gold nanoparticles (PB2MEP-Au) for spectrophotometric detection of uranium (U(VI)) in the ppb level. The developed technique is based on the Localize Surface Plasmon Resonance (LSPR) band intensity quenching, accompanied by a red shift in the wavelength range 523-545 nm at higher concentrations, due to interaction between U(VI) ion and phosphate group bearing PB2MEP-Au. The response was linear in the 5-80 ppb U(VI) concentration range, with LOD of 8.6 ppb. Samples were characterized by transmission electron microscopy, Particle Size Analysis and Zeta Potential measurements to determine morphological transitions upon analyte interaction. Density Functional Theory (DFT) calculations were invoked to study the Au nanoparticle stabilization mechanism, and revealed the interaction of U(VI) with PB2MEP-Au to be thermodynamically spontaneous for the formation of [UO(B2MEP)(HO)] complex, the stability primarily driven by entropy. Interference by other coexisting metal ions was negligible up to interferent:target ratios of 10:1. The method was validated through quantification of U(VI) in water samples spiked with known U(VI) concentrations, the results being in corroboration with those reported using laser fluorimetric method. A T-test confirmed the results derived from the proposed method were not significantly different from those obtained using the standard estimation protocol at a 95% confidence level.
我们描述了用于分光光度法检测十亿分之一水平铀（U(VI)）的稳定的聚（双[2-(甲基丙烯酰氧基)乙基]磷酸酯）（PB2MEP）修饰金纳米颗粒（PB2MEP-Au）的共γ辐射合成。所开发的技术基于局域表面等离子体共振（LSPR）带强度猝灭，在较高浓度下，由于U(VI)离子与带有磷酸基团的PB2MEP-Au之间的相互作用，在523 - 545 nm波长范围内伴随有红移。在5 - 80 ppb的U(VI)浓度范围内响应呈线性，检测限为8.6 ppb。通过透射电子显微镜、粒度分析和zeta电位测量对样品进行表征，以确定分析物相互作用时的形态转变。运用密度泛函理论（DFT）计算来研究金纳米颗粒的稳定机制，并揭示U(VI)与PB2MEP-Au的相互作用对于形成[UO(B2MEP)(HO)]配合物在热力学上是自发的，其稳定性主要由熵驱动。直至干扰物与目标物比例达到10:1时，其他共存金属离子的干扰可忽略不计。通过对添加已知U(VI)浓度的水样中的U(VI)进行定量，验证了该方法，结果与使用激光荧光法报告的结果一致。T检验证实，在95%置信水平下，所提出方法得出的结果与使用标准估计方案获得的结果无显著差异。
