Assessing the contribution of hydroxylation species in the photochemical transformation of primidone (pharmaceutical)
Assessing the contribution of hydroxylation species in the photochemical transformation of primidone (pharmaceutical)
复制标题
评估羟基化物质在扑米酮（药物）光化学转化中的贡献
DOI：
10.1016/j.scitotenv.2019.133826
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发表时间：
2019
影响因子：
9.8
通讯作者：
Song Weihua
中科院分区：
文献类型：
--
作者：
Liu Yingjie;Yan Shuwen;Lian Lushi;Ma Jianzhong;Zhou Huaxi;Song Weihua
药品和个人护理产品（PPCP）是一组经常在水性环境中检测到的新兴污染物。由太阳辐射驱动的光转化是消除PPCPs的最重要的自然过程之一。在这项研究中，扑米酮（PMD）被选为一个模型“光不应”的化合物。通过一系列实验研究了羟基自由基（HO radical dot）、单线态氧（1 O2）和三重态溶解有机物（3DOM dot）等活性中间体（RIs）对模拟太阳辐射下PMD光化学转化的抑制或增强作用。结果表明，HO自由基点在PMD的光降解过程中起着关键作用，溶解氧通过促进HO自由基点的形成而影响PMD的降解速率。研究结果表明，PMD不仅能与自由的HOradical dot反应（HOradical dot-free），还能与低能羟基化试剂反应（HOradical dot-like）。通过甲烷猝灭实验，研究了不同溶解性有机物（DOM）溶液中无点和类点HO自由基对PMD降解的贡献。结果表明，HO自由基点样物种在“光难降解”化合物的光降解中起重要作用。用电子脉冲辐解法测得自由基HOdot与PMD反应的双分子反应速率常数为（5.21 ± 0.02）× 109 M − 1 s − 1。此外，PMD被用来作为一个探针，估计稳态浓度的HO自由基dot-free在各种DOM解决方案。采用正交投影-潜在结构判别分析（OPLS-DA）和系统聚类的多元统计策略，从DOM矩阵中成功识别出28种PMD光化学转化产物（TPs）。
Pharmaceutical and personal care products (PPCPs) are a group of emerging contaminants that have frequently been detected in aqueous environments. Phototransformation driven by solar irradiation is one of the most important natural processes for the elimination of PPCPs. In this study, primidone (PMD) was chosen as a model “photorefractory” compound. A series of experiments were conducted to assess if reactive intermediates (RIs), such as hydroxyl radical (HOradical dot), singlet oxygen (1O2), and triplet states of dissolved organic matter (3DOM⁎), inhibited or enhanced the photochemical transformation of PMD under simulated solar irradiation. The results indicate that HOradical dot plays a key role in the photodegradation of PMD and that dissolved oxygen can affect the degradation rate of PMD by promoting HOradical dot formation. Our results demonstrated that PMD can not only react with free HOradical dot (HOradical dot-free) but also react with lower-energy hydroxylation agents (HOradical dot-like). The contributions of HOradical dot-freeand HOradical dot-liketo PMD degradation in various dissolved organic matter (DOM) solutions were estimated by a methane-quenching experiment. The results indicated that the HOradical dot-likespecies were important in the photodegradation of “photorefractory” compounds. The bimolecular reaction rate constant of the reaction of free HOradical dot with PMD was measured as (5.21 ± 0.02) × 109M−1s−1by using electron pulse radiolysis. Furthermore, PMD was used as a probe to estimate the steady-state concentration of HOradical dot-freein various DOM solutions. Using the multivariate statistical strategies of orthogonal projection to latent structures discriminant analysis (OPLS-DA) and hierarchical clustering, 28 photochemical transformation products (TPs) of PMD were successfully identified from the DOM matrix.