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Li S, Yang J, Li Y, Shi G, Liu Q, Liang Y, Feng Y. Fluorescence Characteristics and Main Fluorescence Component in Burmese 'chameleon' Amber. Spectrochim Acta A Mol Biomol Spectrosc 2024; 314:124201. [PMID: 38579424 DOI: 10.1016/j.saa.2024.124201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 03/04/2024] [Accepted: 03/26/2024] [Indexed: 04/07/2024]
Abstract
One special variety of Burmese amber is "chameleon" amber, named for the bluish-green colour that appears to float on its surface. This material is found in the famous Tengchong market in Yunnan Province, China's largest Burmese amber market. Its bodycolour ranges from golden brown to brownish-red or even red. When exposed to sunlight or strong white light against a black background, its surface shows a uniform green colour. This research presents the gemological properties, spectral characteristics and organic components of Burmese 'chameleon' amber. Three-dimensional (3D) fluorescence spectra showed that Burmese 'chameleon' amber had fluorescence centres near 433, 465 and 470 nm, and the excitation wavelengths of the fluorescence centres of Burmese 'chameleon' amber were shifted from the ultraviolet region (380 ± 10 nm) to the visible region (410 ± 10 nm), with the emission wavelengths concentrated at the bluish-green region. Through the colour simulation and superimposition, the phenomenon of floating bluish-green fluorescence colour of Burmese 'chameleon' amber is not only derived from bluish-green fluorescence centres, but also enhanced by the mixture of surface fluorescence and its bodycolour. Headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) analysis demonstrated the variety of aromatic compounds in Burmese 'chameleon' amber was related to geological process and the presence of fluorescence components. The high-performance liquid chromatography-fluorescence detector obtained some fluorescent aromatics, particularly benzo[a]anthracene with yellowish-green fluorescence, which is responsible for the fluorescence characteristics of Burmese 'chameleon' amber.
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Affiliation(s)
- Shiyi Li
- Gemmological Institute, China University of Geosciences, Wuhan 430074, China; Hubei Gems and Jewelry Engineering Technology Research Centre, Wuhan 430074, China
| | - Jinfeng Yang
- Gemmological Institute, China University of Geosciences, Wuhan 430074, China; Hubei Gems and Jewelry Engineering Technology Research Centre, Wuhan 430074, China
| | - Yan Li
- Gemmological Institute, China University of Geosciences, Wuhan 430074, China.
| | - Guanghai Shi
- School of Gemology, China University of Geosciences, Beijing 100083, China
| | - Qi Liu
- Hunan Key Laboratory of Archaeometry and Conservation Science, Changsha 410005, China; Hunan Museum (The Cultural Relics Appraisal Center of Hunan Provincial), Changsha 410005, China
| | - Youzhi Liang
- Central Academy of Fine Arts, Beijing 100102, China
| | - Yilei Feng
- Gemmological Institute, China University of Geosciences, Wuhan 430074, China; Hubei Gems and Jewelry Engineering Technology Research Centre, Wuhan 430074, China
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Xie M, Lu W, Gu S, Lu J, Wu H, Yao L, Du M, Zhang J, Liu Y, Wang Q. A rapid localization and analysis method for isoquinoline alkaloids with fluorescence in Coptis chinensis Franch. By fabricating the nano-silver sol as a substrate for surface-enhanced Raman spectroscopy. Anal Chim Acta 2024; 1287:342067. [PMID: 38182374 DOI: 10.1016/j.aca.2023.342067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 10/09/2023] [Accepted: 11/22/2023] [Indexed: 01/07/2024]
Abstract
BACKGROUND The quality of traditional Chinese medicines (TCMs) directly impacts their clinical efficacy and drug safety, making standardization a critical component of modern TCMs. Surface-enhanced Raman spectroscopy (SERS) is an effective physical detection method with speed, sensitivity, and suitability for large sample analyses. In this study, a SERS analysis method was developed using a nano-silver sol as the matrix to address the interference of fluorescence components in TCMs and overcome the limitations of traditional detection methods. RESULTS The higher sensitivity and efficiency of SERS was used, enabling detection of a single sample within 30 s. Coptis chinensis Franch. (CCF) was chosen as the model medicine, the nano-silver sol was used as the matrix, and CCF's fourteen main fluorescent alkaloids were tested as index components. Typical signal peaks of the main components in CCF corresponded to the bending deformation of the nitrogen-containing ring plane outer ring system, methoxy stretching vibration, and isoquinoline ring deformation vibration. Through SERS detection of different parts, the distribution content of the main active components in the cortex of CCF was found to be lower than that in the xylem and phloem. Additionally, rapid quality control analyses indicated that among the nine batches of original medicinal materials purchased from Emei and Guangxi, the main active ingredient showed a higher content. SIGNIFICANCE A SERS-based method for the rapid localization and analysis of multiple components of TCMs was established. The findings highlight the potential of SERS as a valuable tool for the analysis and quality control of TCMs, especially for fluorescent components.
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Affiliation(s)
- Minzhen Xie
- Department of Medicinal Chemistry and Natural Medicinal Chemistry, College of Pharmacy, Harbin Medical University, No. 157, Baojian Road, Nangang District, Harbin City, Heilongjiang Province, 150081, China
| | - Wanying Lu
- Department of Medicinal Chemistry and Natural Medicinal Chemistry, College of Pharmacy, Harbin Medical University, No. 157, Baojian Road, Nangang District, Harbin City, Heilongjiang Province, 150081, China
| | - Siqi Gu
- Department of Medicinal Chemistry and Natural Medicinal Chemistry, College of Pharmacy, Harbin Medical University, No. 157, Baojian Road, Nangang District, Harbin City, Heilongjiang Province, 150081, China
| | - Junzhong Lu
- Department of Medicinal Chemistry and Natural Medicinal Chemistry, College of Pharmacy, Harbin Medical University, No. 157, Baojian Road, Nangang District, Harbin City, Heilongjiang Province, 150081, China
| | - Haotian Wu
- Department of Medicinal Chemistry and Natural Medicinal Chemistry, College of Pharmacy, Harbin Medical University, No. 157, Baojian Road, Nangang District, Harbin City, Heilongjiang Province, 150081, China
| | - Le Yao
- Department of Medicinal Chemistry and Natural Medicinal Chemistry, College of Pharmacy, Harbin Medical University, No. 157, Baojian Road, Nangang District, Harbin City, Heilongjiang Province, 150081, China
| | - Menghan Du
- Department of Pharmacology (the State-Province Key Laboratories of Biomedicine Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), College of Pharmacy, Harbin Medical University, No. 157, Baojian Road, Nangang District, Harbin City, Heilongjiang Province, 150081, China
| | - Jianjia Zhang
- Key Laboratory of Chinese Materia Medica, Heilongjiang University of Chinese Medicine, No. 24, Heping Road, Xiangfang District, Harbin City, Heilongjiang Province, 150040, China
| | - Yan Liu
- Key Laboratory of Chinese Materia Medica, Heilongjiang University of Chinese Medicine, No. 24, Heping Road, Xiangfang District, Harbin City, Heilongjiang Province, 150040, China.
| | - Qi Wang
- Department of Medicinal Chemistry and Natural Medicinal Chemistry, College of Pharmacy, Harbin Medical University, No. 157, Baojian Road, Nangang District, Harbin City, Heilongjiang Province, 150081, China.
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Yu F, Li X, Zhang R, Guo J, Yang W, Tripathee L, Liu L, Wang Y, Kang S, Cao J. Insights into dissolved organics in non-urban areas - Optical properties and sources. Environ Pollut 2023; 329:121641. [PMID: 37100371 DOI: 10.1016/j.envpol.2023.121641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 03/28/2023] [Accepted: 04/12/2023] [Indexed: 05/21/2023]
Abstract
Brown carbon aerosols show obvious light absorption properties in the ultraviolet-visible (UV-Vis) range, which has an important impact on photochemistry and climate. In this study, experimental samples originated from the North slope of the Qinling Mountains (at two remote suburb sites) to study the optical properties of water-soluble brown carbon (WS-BrC) in PM2.5. The WS-BrC of TY (a sampling site on the edge of Tangyu of Mei county) has a stronger light absorption ability than CH (a rural sampling site, near the Cuihua Mountains scenic spot). The direct radiation effect of WS-BrC relative to elemental carbon (EC) is 6.67 ± 1.36% in TY and 24.13 ± 10.84% in CH in the UV range, respectively. In addition, two humic-like and one protein-like fluorophore components in WS-BrC were identified by fluorescence spectrum and parallel factor (EEMs-PARAFAC). Humification index (HIX), biological index (BIX) and fluorescence index (FI) together showed that the WS-BrC in the two sites may originate from fresh aerosol emissions. Potential source analysis of Positive Matrix Factorization (PMF) model show that the combustion process, vehicle, secondary formation and road dust are the main contributors to WS-BrC.
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Affiliation(s)
- Feng Yu
- School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi'an, 710021, China
| | - Xiaofei Li
- School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi'an, 710021, China; Key Laboratory of Aerosol Chemistry and Physics, State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China; State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China.
| | - Rui Zhang
- School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi'an, 710021, China
| | - Jingning Guo
- School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi'an, 710021, China
| | - Wen Yang
- School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi'an, 710021, China
| | - Lekhendra Tripathee
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Lang Liu
- School of Public Policy and Administration, Northwestern Polytechnical University, Xi'an, 710129, China
| | - Yuqin Wang
- School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi'an, 710021, China
| | - Shichang Kang
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Junji Cao
- Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, 100029, China
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Bao Y, Huang T, Ning C, Sun T, Tao P, Wang J, Sun Q. Changes of DOM and its correlation with internal nutrient release during cyanobacterial growth and decline in Lake Chaohu, China. J Environ Sci (China) 2023; 124:769-781. [PMID: 36182182 DOI: 10.1016/j.jes.2022.02.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 02/11/2022] [Accepted: 02/14/2022] [Indexed: 06/16/2023]
Abstract
The seasonal changes in dissolved organic matter (DOM), and its correlation with the release of internal nutrients during the annual cycle of cyanobacteria in the eutrophic Lake Chaohu, China, were investigated from four sampling periods between November 2020 and July 2021. The DOM fluorescence components were identified as protein-like C1, microbial humic-like C2, and terrestrial humic-like C3. The highest total fluorescence intensity (FT) of DOM in sediments during the incubation stage is due to the decomposition and degradation of cyanobacteria remains. The lowest humification of DOM and the highest proportion of C1 in waters during the initial cyanobacterial growth indicate that fresh algae are the main source. The highest molecular weight of DOM and FT of the C2 in sediments during cyanobacterial outbreaks indicate the concurrent deposition of undegraded cyanobacterial remains and microbial degradation. The components of DOM are affected mainly by the dissolved total phosphorus in waters, while the temperature drives the annual cycle of cyanobacteria. The decreasing C1 in sediments and increasing nutrients in waters from the cyanobacterial incubation to outbreak indicate that mineralization of algal organic matter contributes importantly to the release of internal nutrients, with the strongest release of phosphorus observed during the early growth of cyanobacteria. The humic-like C2 and C3 components could also affect the dynamics of internal phosphorus through the formation of organic colloids and organic-inorganic ligands. The results show that the degradation of DOM leads to nutrients release and thus supports the continuous growth of cyanobacteria in eutrophic Lake Chaohu.
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Affiliation(s)
- Yan Bao
- School of Resources and Environmental Engineering, Anhui University, Hefei 230601, China
| | - Tao Huang
- School of Resources and Environmental Engineering, Anhui University, Hefei 230601, China; Anhui Province Key Laboratory of Wetland Ecosystem Protection and Restoration, Anhui University, Hefei 230601, China.
| | - Chengwu Ning
- School of Resources and Environmental Engineering, Anhui University, Hefei 230601, China
| | - Tingting Sun
- School of Resources and Environmental Engineering, Anhui University, Hefei 230601, China
| | - Pengliang Tao
- School of Resources and Environmental Engineering, Anhui University, Hefei 230601, China
| | - Jie Wang
- School of Resources and Environmental Engineering, Anhui University, Hefei 230601, China
| | - Qingye Sun
- School of Resources and Environmental Engineering, Anhui University, Hefei 230601, China; Anhui Province Key Laboratory of Wetland Ecosystem Protection and Restoration, Anhui University, Hefei 230601, China
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Zhang C, Chen M, Kang S, Yan F, Han X, Gautam S, Hu Z, Zheng H, Chen P, Gao S, Wang P, Li C. Light absorption and fluorescence characteristics of water-soluble organic compounds in carbonaceous particles at a typical remote site in the southeastern Himalayas and Tibetan Plateau. Environ Pollut 2021; 272:116000. [PMID: 33199066 DOI: 10.1016/j.envpol.2020.116000] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 11/03/2020] [Accepted: 11/04/2020] [Indexed: 05/25/2023]
Abstract
Carbonaceous particles play an important role in climate change, and an increase in their emission and deposition causes glacier melting in the Himalayas and the Tibetan Plateau (HTP). This implies that studying their basic characteristics is crucial for a better understanding of the climate forcing observed in this area. Thus, we investigated characteristics of carbonaceous particles at a typical remote site of southeastern HTP. Organic carbon and elemental carbon concentrations at this study site were 1.86 ± 0.84 and 0.18 ± 0.09 μg m-3, respectively, which are much lower than those reported for other frequently monitored stations in the same region. Thus, these values reflect the background characteristics of the study site. Additionally, the absorption coefficient per mass (α/ρ) of water-soluble organic carbon (WSOC) at 365 nm was 0.60 ± 0.19 m2 g-1, with the highest and lowest values corresponding to the winter and monsoon seasons, respectively. Multi-dimensional fluorescence analysis showed that the WSOC consisted of approximately 37% and 63% protein and humic-like components, respectively, and the latter was identified as the component that primarily determined the light absorption ability of the WSOC, which also showed a significant relationship with some major ions, including SO2-4, K+, and Ca2+, indicating that combustion activities as well as mineral dust were two important contributors to WSOC at the study site.
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Affiliation(s)
- Chao Zhang
- CAS Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Meilian Chen
- Environmental Program, Guangdong Technion-Israel Institute of Technology, Shantou, 515063, China
| | - Shichang Kang
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing, 100101, PR China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Fangping Yan
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China; LUT School of Engineering Science, Lappeenranta University of Technology, P.O. Box 20, 53851, Lappeenranta, Finland
| | - Xiaowen Han
- CAS Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China; College of Geomatics and Geoinformation, Guilin University of Technology, 12 Jiangan Road, Guilin, 541004, China
| | - Sangita Gautam
- CAS Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhaofu Hu
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Huijun Zheng
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Pengfei Chen
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Shaopeng Gao
- CAS Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Pengling Wang
- National Climate Center, China Meteorological Administration, Beijing, 100081, China
| | - Chaoliu Li
- CAS Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China; State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing, 100101, PR China.
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Bai Y, Zhou Y, Che X, Li C, Cui Z, Su R, Qu K. Indirect photodegradation of sulfadiazine in the presence of DOM: Effects of DOM components and main seawater constituents. Environ Pollut 2021; 268:115689. [PMID: 33069046 DOI: 10.1016/j.envpol.2020.115689] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 09/12/2020] [Accepted: 09/15/2020] [Indexed: 06/11/2023]
Abstract
The presence of pharmaceuticals and personal care products in coastal waters has caused concern over the past decade. Sulfadiazine (SD) is a very common antibiotic widely used as human and fishery medicine, and dissolved organic matter (DOM) plays a significant role in the indirect photodegradation of SD; however, the influence of DOM compositions on SD indirect photodegradation is poorly understood. The roles of reactive intermediates (RIs) in the indirect photolysis of SD were assessed in this study. The reactive triplet states of DOM (3DOM∗) played a major role, whereas HO· and 1O2 played insignificant roles. DOM was divided into four components using excitation-emission matrix spectroscopy combined with parallel factor analysis. The components included three allochthonous humic-like components and one autochthonous humic-like component. The allochthonous humic-like components contributed more to RIs generation and SD indirect photolysis than the autochthonous humic-like component. A significant relationship between the indirect photodegradation of SD and the decay of DOM fluorescent components was found (correlation coefficient, 0.99), and the different indirect photodegradation of SD in various DOM solutions might be ascribed to the different components of DOM. The indirect photolysis rate of SD first increased and then decreased with increasing pH. SD photolysis was enhanced by low salinity but remained stable at high salinity. The increased carbonate concentration inhibited SD photolysis, whereas nitrate showed almost no effect in this study.
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Affiliation(s)
- Ying Bai
- Key Laboratory of Sustainable Development of Marine Fisheries, Ministry of Agriculture and Rural Affairs, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, 266071, China; Laboratory for Marine Fisheries Science and Food Production Processes, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, 266071, China
| | - Yanlei Zhou
- Jimo Comprehensive Inspection and Testing Center, Qingdao, 266200, China
| | - Xiaowei Che
- Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao, 266100, China
| | - Conghe Li
- Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao, 266100, China
| | - Zhengguo Cui
- Key Laboratory of Sustainable Development of Marine Fisheries, Ministry of Agriculture and Rural Affairs, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, 266071, China; Laboratory for Marine Fisheries Science and Food Production Processes, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, 266071, China
| | - Rongguo Su
- Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao, 266100, China.
| | - Keming Qu
- Key Laboratory of Sustainable Development of Marine Fisheries, Ministry of Agriculture and Rural Affairs, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, 266071, China; Laboratory for Marine Fisheries Science and Food Production Processes, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, 266071, China.
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Bai Y, Cui Z, Su R, Qu K. Influence of DOM components, salinity, pH, nitrate, and bicarbonate on the indirect photodegradation of acetaminophen in simulated coastal waters. Chemosphere 2018; 205:108-117. [PMID: 29689524 DOI: 10.1016/j.chemosphere.2018.04.087] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 04/12/2018] [Accepted: 04/15/2018] [Indexed: 06/08/2023]
Abstract
The indirect photodegradation behaviors of acetaminophen (APAP) were investigated in the presence of four kinds of dissolved organic matter (DOM) and were also assessed in the presence of seawater components and conditions such as salinity, pH, nitrate and bicarbonate. The results showed three important findings: firstly, in the indirect photolysis of APAP, the contributions of 3DOM*, ·OH and 1O2 were >85.0%, 2.3-9.9% and 0.8-2.6% at pH 8.0. Secondly, DOM was divided into four terrestrial humic-like components by Excitation-emission matrix spectroscopy (EEMs) combined with parallel factor analysis (PARAFAC). This study showed a good linearity between DOM fluorescence components and the indirect photodegradation of APAP (R2 = 0.92) and the differences in photodegradation rates of APAP among various DOM solutions were due to the diverse compositions of DOM. Finally, salinity was an important factor influencing the removal of APAP, and the APAP photodegradation rate constants increased from (3.33 ± 0.07) × 10-5 s-1 to (1.25 ± 0.05) × 10-4 s-1 with increasing salinity. The increased pseudo-first-order rate constants for photolysis of APAP with increasing salinity, pH and nitrate were attributed to the enhanced generation of reactive intermediates (RI) and easier reactions between RI and APAP. The increased APAP removal rate constant with increasing bicarbonate was likely ascribed to the yield of ∙CO3-. This is the first report of the roles of DOM components and salinity on the indirect photolysis of APAP. These findings would be essential to predict the photochemical fate of APAP and would also allow for a better understanding of the environmental fate of other phenolic contaminants.
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Affiliation(s)
- Ying Bai
- Key Laboratory of Sustainable Development of Marine Fisheries, Ministry of Agriculture, Qingdao National Laboratory for Marine Science and Technology, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China
| | - Zhengguo Cui
- Key Laboratory of Sustainable Development of Marine Fisheries, Ministry of Agriculture, Qingdao National Laboratory for Marine Science and Technology, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China
| | - Rongguo Su
- Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China.
| | - Keming Qu
- Key Laboratory of Sustainable Development of Marine Fisheries, Ministry of Agriculture, Qingdao National Laboratory for Marine Science and Technology, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China.
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