Analytical methods for the determination of several natural and synthetic steroids in water and solid samples were developed using liquid chromatography tandem mass spectrometry. Atmospheric pressure photoionization (APPI) in positive mode was used as the source which appeared to reduce background and interferences as compared to electrospray ionization. Toluene was identified as the most appropriate dopant and its concentration optimized to enhance ionization efficiency. Method detection limits were in the low-nanogram-per-liter range for water samples using on-line solid-phase extraction and near 0.2 ng/g using microwave-assisted solvent extraction for solid samples. This on-line method, using APPI as a source and toluene as a dopant, is beneficial as it saves time due to on-line extraction and reduces interference and matrix effects using gas-phase photoionization. Groundwater, wastewater, runoff, and soil samples were collected and analyzed using the method indicating that traces of several androgens, estrogens, and other steroid-like compounds do occur in samples impacted by animal waste.
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http://dx.doi.org/10.1007/s00216-012-6572-8 | DOI Listing |
Nat Commun
January 2025
School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, China.
Stereocontrolled construction of tetrasubstituted olefins has been an attractive issue yet remains challenging for synthetic chemists. In this manuscript, alkynyl selenides, when treated with ArBCl, are subject to an exclusive 1,1-carboboration, affording tetrasubstituted alkenes with excellent levels of E-selectivity. Detailed mechanistic studies, supported by DFT calculations, elucidates the role of selenium in this 1,1-addition process.
View Article and Find Full Text PDFNat Commun
January 2025
College of Chemistry, Nankai University, Tianjin, China.
Pathogenic intracellular bacteria pose a significant threat to global public health due to the barriers presented by host cells hindering the timely detection of hidden bacteria and the effective delivery of therapeutic agents. To address these challenges, we propose a tandem diagnosis-guided treatment paradigm. A supramolecular sensor array is developed for simple, rapid, accurate, and high-throughput identification of intracellular bacteria.
View Article and Find Full Text PDFEnviron Res
January 2025
Marine Elements and Marine Environment Division, CSIR-Central Salt & Marine Chemicals Research Institute, Bhavnagar-364 002 (Gujarat), India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India. Electronic address:
Biofouling is a common phenomenon caused by waterborne organisms such as bacteria, diatoms, mussels, barnacles, algae, etc., accumulating on the surfaces of engineering structures submerged under water. This leads to corrosion of such surfaces and decreases their moving efficiency.
View Article and Find Full Text PDFJ Environ Manage
January 2025
Fujian Province Key Laboratory of Pollution Control and Resource Reuse, College of Environmental and Resource Science, Fujian Normal University, Fuzhou, 350007, Fujian Province, China. Electronic address:
Since the widespread use of antibiotics, the residues of antibiotics have frequently been detected in various water sources, making antibiotic pollution an urgent environmental issue. In this paper, one-step green synthetic reduced graphene/manganese nanoparticles (rGO/Mn NPs) composites have been utilized as a novel environmentally-friendly catalyst for tetracycline (TC) removal. The results demonstrated that rGO/Mn NPs exhibit excellent adsorption performance for TC, and can efficiently activate sodium persulfate (PDS) to oxidize and degrade TC.
View Article and Find Full Text PDFJ Environ Manage
January 2025
Institute of Blue and Green Development, Shandong University, Weihai, 264209, China; Faculty of Finance, City University of Macau, Macao, China. Electronic address:
Owing to critical policy significance, a growing body of literature has been predominantly concentrating on the social welfare benefits brought by green finance (GF) initiatives. However, there is a paucity of research that quantifies the economic costs of GF initiatives on carbon reduction, raising the increasing concerns about the irreconcilable climate-economy trade-offs. To end this, the present study systematically investigates the influence of GF initiatives on the carbon-related marginal abatement cost (MAC) using two competing hypotheses: regulatory versus technical effects.
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