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The dispersion of harmful oil components into the ocean waters could pose long-term risks to flora and fauna. Due to the complexity of oil-contaminated sites, the unambiguous identification and quantitation of environmental pollutants often requires the sequence of high-performance liquid chromatography and gas chromatography-mass spectrometry. A classic example is the analysis of polycyclic aromatic hydrocarbons. This article tackles a different aspect of environmental analysis as it focuses on the Shpol'skii spectroscopy of polycyclic aromatic sulfur heterocycles, specifically those belonging to the subgroups often known as anthrathiophenes and benzonaphthothiophenes. Photoluminescence measurements were made with a commercial spectrofluorimeter equipped with a continuous wave excitation source for steady state measurements and a pulsed excitation source for time-resolved measurements in the phosphorescence time domain. To the extent of our literature search, this is the first report on the 4.2 K fluorescence and phosphorescence spectra of anthrathiophenes and benzonaphthothiophenes, and the 77 K and 4.2 K phosphorescence lifetimes of benzonaphthothiophenes. 77 K and 4.2 K analytical figures of merit revealed the possibility to detect the studied compounds at the parts-per-billion (ng mL −1) concentration levels. The spectral and lifetime data gathered in this article provides the required information to choose an appropriate photoluminescence technique for the analysis of four-ring polycyclic aromatic sulfur heterocycles in complex environmental extracts.

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In current article an easy and selective method is proposed for spectrophotometric estimation of metoclopramide (MCP) in pharmaceutical preparations using cloud point extraction (CPE) procedure. The method involved reaction between MCP with 1-Naphthol in alkali conditions using Triton X-114 to form a stable dark purple dye. The Beer’s law limit in the range 0.34-9 μg mL-1 of MCP with r =0.9959 (n=3) after optimization. The relative standard deviation (RSD) and percentage recoveries were 0.89 %, and (96.99–104.11%) respectively. As well, using surfactant cloud point extraction as a method to extract MCP was reinforced the extinction coefficient(ε) to 1.7333×105L/mol.cm in surfactant-rich phase. The small volume of organic solvent (500mL/sample) provides an environmentally friendly and low-cost preconcentration method. The suggested method was utilized for analyzing of MCP in commercial pharmaceutical injections.

a b s t r a c tBenzo[a]pyrene (B[a]P) is a prototypic carcinogenic polycyclic aromatic hydrocarbon (PAH), which requires metabolic activation to produce its detrimental effects. Measurement of B[a]P metabolites in human urine could provide a direct way to assess individual differences in susceptibility to PAH-related cancer. This article focuses on the development of screening methodology for the routine analysis of B[a]P metabolites in urine samples. It explores the solid-surface room-temperature fluorescence (RTF) properties of 3-hydroxybenzo[a]pyrene, benzo[a]pyrene-trans-9,10-dihydrodiol, benzo[a]pyrene-r-7,t-8,c-9-tetrahydrotriol and benzo[a]pyrene-r-7,t-8,c-9,c-10-tetrahydrotetrol previously extracted from urine samples with octadecyl-silica membranes. Relative standard deviations varying from 2.1% (benzo[a]pyrene-r-7,t-8,c-9-tetrahydrotriol) to 8.6% (3-hydroxy-benzo[a]pyrene) are obtained with the aid of fiber optic probe that eliminates the need for manual optimization of signal intensities. Analytical recoveries from human urine samples varied from 87.5 ± 3.1% (3-hydroxy-benzo[a]pyrene) to 99.8 ± 2.5% (benzo[a]pyrene-r-7,t-8,c-9,c-10-tetrahydrotetrol). The excellent analytical figures of merit and the simplicity of the experimental procedure demonstrate the potential of this approach for screening biomarkers of PAH exposure in numerous urine samples.