El-Raheem Hany Abd, Hassan Rabeay Y A, Khaled Rehab, Farghali Ahmed, El-Sherbiny Ibrahim M
Center of Materials Sciences, Zewail City of Science and Technology October Gardens, 6th of October City 12578 Giza Egypt
Materials Science and Nanotechnology Department, Faculty of Postgraduate Studies for Advanced Sciences, Beni-Suef University Beni-Suef Egypt.
RSC Adv. 2021 Sep 28;11(50):31845-31854. doi: 10.1039/d1ra03693a. eCollection 2021 Sep 21.
A new electrochemical sensor has been fabricated based on the synthesis of poly(ester-urethane) urea (PUU) doped with gold nanoparticles (AuNPs), and the obtained composite materials (PUU/AuNPs) were used as a new sensing platform for highly sensitive and selective detection of mercury(II) ions in fish tissue. PUU was synthesized and fully characterized by XRD, TGA, DSC, and FTIR to analyze the chemical structure, thermal stability, and morphological properties. As a polymeric structure, the PUU consists of urethane and urea groups that possess pronounced binding abilities to Hg ions. SEM-EDX was carried out to confirm this kind of interaction. Using ferricyanide as the redox probe, PUU alone exhibited weak electrochemical signals due to its low electrical conductivity. Therefore, a new series of nanocomposites of PUU with different nanostructured materials were applied, and their electrochemical performances were evaluated. Among these materials, the PUU/AuNP-modified electrode showed high voltammetric signals towards Hg. Consequently, the parameters affecting the performance of the assay, such as electrode composition, scan rate, and sensing time, as well as the effect of electrolyte and pH were studied and optimized. The sensor showed a linear range of 5 ng mL to 155 ng mL with the regression coefficient = 0.986, while the calculated values of the limit of detection (LOD) and limit of quantification (LOQ) were 0.235 ng mL and 0.710 ng mL, respectively. In terms of cross reactivity testing, the sensor exhibited a high selectivity against heavy metals which are commonly determined in seafood (Cd, Pb, As, Cr, Mg, and Cu). For real applications, total Hg ions in fish tissue were determined with very high recovery and no prior complicated treatments.
基于掺杂金纳米颗粒（AuNPs）的聚（酯 - 聚氨酯）脲（PUU）的合成制备了一种新型电化学传感器，所得复合材料（PUU/AuNPs）被用作一种新型传感平台，用于高灵敏度和选择性地检测鱼组织中的汞（II）离子。通过XRD、TGA、DSC和FTIR对PUU进行了合成及全面表征，以分析其化学结构、热稳定性和形态学性质。作为一种聚合物结构，PUU由对汞离子具有显著结合能力的聚氨酯和脲基团组成。通过扫描电子显微镜 - 能谱仪（SEM - EDX）来证实这种相互作用。以铁氰化物作为氧化还原探针，单独的PUU由于其低电导率而表现出微弱的电化学信号。因此，应用了一系列不同纳米结构材料与PUU的新型纳米复合材料，并对其电化学性能进行了评估。在这些材料中，PUU/AuNP修饰电极对汞表现出高伏安信号。因此，研究并优化了影响检测性能的参数，如电极组成、扫描速率、传感时间，以及电解质和pH的影响。该传感器的线性范围为5 ng/mL至155 ng/mL，回归系数为0.986，而计算得到的检测限（LOD）和定量限（LOQ）分别为0.235 ng/mL和0.710 ng/mL。在交叉反应性测试方面，该传感器对海鲜中常见的重金属（镉、铅、砷、铬、镁和铜）具有高选择性。对于实际应用，鱼组织中的总汞离子在无需事先复杂处理的情况下以非常高的回收率被测定。
