UNS: Class-Specific Transformations of Antibiotics in UV-Based Water/Wastewater Treatment Processes

1510420Blaney拟议的工作重点是三类抗生素的紫外光转化反应：氟喹诺酮类、四环素类和磺胺类。这些类别中的重磅炸弹药物(如环丙沙星、四环素、磺胺甲恶唑)已被广泛研究；然而，这些化合物在紫外线驱动的水/废水处理过程中的行为不一定延伸到同一类别中的其他化合物。此外，存在将抗生素转化为其他抗生素的潜力。这个项目的总体目标是全面了解来自三个关键抗生素类别的40种化合物的紫外线反应。该项目将包括令人关注的抗生素，包括15种氟喹诺酮类、10种四环素类和15种磺胺类药物。这个假设是，在基于紫外线的过程中，存在着从抗生素向抗生素转化的巨大潜力。在水/废水处理过程中产生抗生素的这一途径对于降低与成品水和废水中抗生素浓度相关的风险至关重要。这一假设将通过以下具体目标得到验证：1.建立40种抗生素的在线固相萃取高效液相色谱-电喷雾电离串联质谱仪分析方法。2.测定合成溶液、出水和废水中羟基自由基对253.7 nm紫外光的反应动力学和抗生素转化作用。3.确定每一类抗生素到抗生素的转化，并构建反应路径，以证明紫外线处理后残留的抗菌活性的潜力。4.表征含有紫外线转化产物的处理溶液(即合成水、饮用水和废水)的残留抗菌活性。这种方法是一种多管齐下的研究战略，将增加对水和废水中日益重要的一类化学物质命运的了解。在特定的类别中，人们对抗生素到抗生素的转化的认识仅限于自然系统，而不是人工设计的紫外线过程。这项拟议的研究代表了一项变革性的研究，它挑战了围绕抗生素在紫外线过程中的转化的传统智慧。这个项目的另一个变革性特点来自于强调以班级为基础的方法来研究药物和个人护理产品，而不是对化学上不同的分子进行大规模调查。拟议研究的预期收益包括测量比摩尔吸光系数、量子产率和基于通量的准一级速率常数；确定抗生素与羟基自由基反应的二级速率常数；鉴定抗生素的光转化产物/途径；以及表征转化产物的毒性。为了更好地了解国家处方药回收日计划在防止药品进入水环境方面的影响，PI将与DEA特别代理合作，收集有关未来收集的定量数据。特别是，PI建议每年识别和集中存放在UMBC和霍华德县警察局的所有处方药。

1510420BlaneyThe proposed work focuses on ultraviolet-based transformation reactions for three classes of antibiotics: fluoroquinolones, tetracyclines, and sulfonamides. The blockbuster drugs (e.g., ciprofloxacin, tetracycline, sulfamethoxazole) in these classes have been extensively studied; however, the behavior of these compounds during ultraviolet -driven water/wastewater treatment processes does not necessarily extend to other compounds within the same class. Furthermore, a potential for antibiotic transformation into other antibiotics exists. The overall objective of this project is to provide a comprehensive understanding of ultraviolet-based reactions of 40 compounds from three critical antibiotic classes.The project will include antibiotics of concern including 15 fluoroquinolones, 10 tetracyclines, and 15 sulfonamides. The hypothesis is that a significant potential for antibiotic-to-antibiotic transformation exists during ultraviolet -based processes. This avenue for antibiotic generation during water/wastewater treatment is critical to lowering the risks associated with antibiotic concentrations in finished water and wastewater effluent. This hypothesis will be tested by the following Specific Aims: 1. To develop an online solid-phase extraction liquid chromatography electrospray ionization tandem mass spectrometry analytical method for 40 antibiotics. 2. To measure reaction kinetics and antibiotic transformation with ultraviolet light at 253.7 nm and hydroxyl radicals in synthetic solutions, finished water, and wastewater effluent. 3. To identify antibiotic-to-antibiotic transformations within each class and construct reaction pathways to demonstrate potential for residual antimicrobial activity after ultraviolet treatment. 4. To characterize the residual antimicrobial activity of treated solutions (i.e., synthetic, drinking water, and wastewater) containing ultraviolet transformation products. The approach is a multi-pronged research strategy which will increase understanding of the fate of an increasingly important class of chemicals in water and wastewater. Awareness of antibiotic-to-antibiotic transformations within specific classes has been confined to natural systems, not engineered ultraviolet processes. The proposed study represents transformative research that challenges conventional wisdom surrounding transformation of antibiotics in ultraviolet processes. Another transformative quality of this project derives from the emphasis on a class-based approach to study of pharmaceutical and personal care products, rather than a large investigation of chemically-diverse molecules. The expected benefits of the proposed research include measurement of specific molar absorptivity, quantum yield, and fluence-based pseudo-first order rate constants; determination of second-order rate constants for antibiotic reaction with hydroxyl radicals; identification of phototransformation products/pathways for antibiotics; and characterization of the toxicity of transformation products. To better understand the impact of the national prescription drug take-back day program on preventing pharmaceuticals from entering the aquatic environment, the PI will be working with a DEA Special Agent to gather quantitative data on future collections. In particular, the PI proposes identifying and massing all prescription drugs deposited at the UMBC and Howard County Police Departments each year.