Abstract：
High-resolution identification of chromium (Cr) species, especially various organic-Cr complexes, in a convenient and economically-feasible manner is the prerequisite for achieving the advanced treatment of chromium wastewater. To this end, a colorimetric nano-Au sensor array was developed by taking advantage of the UV-spectra shift of gold nanoparticles (Au NPs) upon interaction with Cr species; specifically, four molecular modifiers [i.e., iminodiacetic acid (IDA), tripolyphosphate (TPP), cetyltrimethylammonium bromide (CTAB), and 1,5-diphenylcarbazide (DPC)] were intentionally employed for assembling nano-Au array receptors, which showed respective responses toward different Cr species through the formation of coordination, hydrophobic interaction, electrostatic attraction, and redox reaction, respectively; the \"fingerprint\" differences of the unique optical properties were then integrated for semi-quantitatively recognizing Cr species by pattern recognition techniques. Eleven ubiquitous Cr species [i.e., Cr(III), Cr(VI), and various Cr(III)-organic complexes] served as the model samples, which could be sensitively identified, no matter in individual or mixture mode, by the developed nano-Au sensor array on the basis of the colorimetric responses resulted from diverse nano-Au-aggregation behaviors, with excellent anti-interference ability in the simulated or actual water scenario. Attractively, the nano-Au sensor array can achieve very sensitive detection limit of the quantitative analyses of Cr species in a prompt in-situ manner, which usually requires a two-step process of separation and detection for the conventional analytical methods. Such a convenient strategy of Cr species discrimination conduces to rationally designing specific protocols for the advanced treatment of chromium wastewater.
摘要：
铬（Cr）物种的高分辨率识别，特别是各种有机Cr配合物，以方便和经济可行的方式是实现铬废水深度处理的前提。为此,通过利用金纳米粒子（AuNP）与Cr物种相互作用时的紫外光谱位移，开发了比色纳米Au传感器阵列；特别是，四种分子改性剂[即，亚氨基二乙酸（IDA），三聚磷酸盐（TPP），十六烷基三甲基溴化铵（CTAB），和1,5-二苯基卡巴肼（DPC）]有意用于组装纳米Au阵列受体，通过形成配位对不同的Cr物种表现出各自的响应，疏水相互作用，静电吸引,和氧化还原反应，然后分别整合了独特光学特性的“指纹”差异，以通过模式识别技术半定量识别Cr物种。11种普遍存在的Cr物种[即，Cr(III),Cr(VI),和各种Cr(III)-有机络合物]作为模型样品，可以敏感地识别，无论在单独或混合模式下，通过开发的纳米Au传感器阵列，基于不同的纳米Au聚集行为产生的比色响应，在模拟或实际水场景中具有出色的抗干扰能力。有吸引力的,纳米Au传感器阵列可以快速原位实现Cr物种定量分析的非常灵敏的检测限，这通常需要对常规分析方法进行两步分离和检测。这种方便的Cr物种区分策略有助于合理设计用于铬废水深度处理的特定方案。
