AbstractPorous uranium oxide hollow sphere nanoparticles were synthesized in ionic liquids under hydrothermal conditions. Various precipitating agents and ionic liquids were investigated to determine their respective impact on the resultant uranium oxide morphologies. Using hydrazine hydrate as precipitating agent and N-butyl pyridinium bromide as templating agent, a porous-hollow structure was created with a surface area of 1958 m2.g−1 and an average pore diameter of 30 nm. The nanoparticles revealed high peroxidase-mimicking activity. This was evaluated by using the peroxidase substrate 3,3′,5,5′-tetramethylbenzidine (TMB) that is catalytically oxidized by H2O2 to give oxidized TMB (oxTMB) which is blue (with an absorption peak at 652 nm). The material was used as a nanozyme for colorimetric detection of Sn2+. Meanwhile, it is found that BSA strongly improves the catalytic activity of the nanozyme, while Sn(II) inhibits its activity. Thus, a colorimetric method for Sn2+ detection was designed. The method works in the 0.5–100 μM Sn(II) concentration range and has a lower detection limit of 0.36 μM (at S/N = 3). Graphical abstractThe catalytic activity of porous-hollow nano-UO2 toward the oxidation of 3,3′,5,5′-tetramethylbenzidine by H2O2 is remarkably improved in the presence of bovine serum albumin, while tin(II) inhibits its activity. This finding has been applied to design a method for colorimetric quantification of tin(II) in water samples.

中文翻译：

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具有过氧化物酶模拟活性的多孔氧化铀空心纳米球的制备：应用于比色测定锡（II）

摘要 在离子液体中水热条件下合成了多孔氧化铀空心球纳米粒子。研究了各种沉淀剂和离子液体，以确定它们各自对所得氧化铀形态的影响。以水合肼为沉淀剂，N-丁基溴化吡啶鎓为模板剂，形成了比表面积为1958 m2.g-1、平均孔径为30 nm的多孔中空结构。纳米颗粒显示出高过氧化物酶模拟活性。这通过使用过氧化物酶底物 3,3',5,5'-四甲基联苯胺 (TMB) 进行评估，该底物被 H2O2 催化氧化，得到蓝色的氧化 TMB (oxTMB)（在 652 nm 处有吸收峰）。该材料用作纳米酶，用于比色检测 Sn2+。同时，结果表明，BSA 极大地提高了纳米酶的催化活性，而 Sn(II) 则抑制了其活性。因此，设计了一种用于 Sn2+ 检测的比色方法。该方法在 0.5–100 μM Sn(II) 浓度范围内工作，检测下限为 0.36 μM（S/N = 3）。图形摘要在牛血清白蛋白的存在下，多孔中空纳米UO2 对H2O2 氧化3,3',5,5'-四甲基联苯胺的催化活性显着提高，而锡(II) 抑制其活性。这一发现已被应用于设计一种水样中锡 (II) 的比色定量方法。5–100 μM Sn(II) 浓度范围，检测下限为 0.36 μM（S/N = 3）。图形摘要在牛血清白蛋白的存在下，多孔中空纳米UO2 对H2O2 氧化3,3',5,5'-四甲基联苯胺的催化活性显着提高，而锡(II) 抑制其活性。这一发现已被应用于设计一种水样中锡 (II) 的比色定量方法。5–100 μM Sn(II) 浓度范围，检测下限为 0.36 μM（S/N = 3）。图形摘要在牛血清白蛋白的存在下，多孔中空纳米UO2 对H2O2 氧化3,3',5,5'-四甲基联苯胺的催化活性显着提高，而锡(II) 抑制其活性。这一发现已被应用于设计一种水样中锡 (II) 的比色定量方法。