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81.
Fast separations are very desirable in laboratories that analyze large numbers of samples per day or those needing short turn‐around times. Traditional HPLC methods using conventional stationary phases and standard column dimensions require significant amounts of organic solvents and generate large volumes of waste. With growing awareness about the environment, the development of green technologies has been receiving increasing attention. In this work, a very fast green analytical method based on LC‐UV using a short narrow bore column packed with fully porous sub‐2 μm particles has been developed for simultaneous determination of nine pharmaceuticals in wastewater and surface water. The chromatographic separation was optimized in order to achieve short analysis time and good resolution for all analytes in a single run. All analytes could be separated in 1 min with good resolution. Sample preparation was executed by solid phase extraction using Oasis HLB cartridges. The method developed was validated based on parameters such as linearity, precision, accuracy, detection, and quantification limits. The recovery ranged from 70.9 to 92.5% with SDs not higher than 5.4%, except for acetaminophen and sulphanilamide. LODs ranged from 0.6–2.5 μg/L, while the LOQs were in the range 2–8 μg/L. 相似文献
82.
A rapid, efficient, and new solvent terminated dispersive liquid–liquid microextraction technique coupled with HPLC was developed for selective extraction and analysis of s‐triazine herbicides from environmental water samples. Important parameters influencing the extraction process including type and volume of extraction and disperser solvent, extraction time, sample pH, ionic strength, and extraction temperature were successfully optimized. Under the optimal conditions, there are excellent linear relationships between the analytical results and concentration in the range of 10–400 mg/L for atrazine, propazine, prometryn, and terbutryn. LOD and LOQ ranged from 0.60 to 2.33 μg/L and 2.0 to 7.7 μg/L, respectively. Performance of the analytical technique was evaluated by carrying out the repeatability and reproducibility analyses that were ranged from 2.86 to 5.66% and 4.64 to 5.89% for 100 μg/L of each target analyte, respectively. The proposed method has been successfully applied to the analysis of real water samples and acceptable relative recoveries over the range of 65.93–101.46%, with RSDs ≤ 8.80%, were obtained. The overall results have been compared with the literature values. Thus, the method developed could efficiently be used for selective extraction of the target analytes from complex matrices, particularly environmental waters. 相似文献
83.
Shigekazu Usuda Kenichiro Yasuda Yoko Saito-Kokubu Fumitaka Esaka Chi-Gyu Lee Masaaki Magara 《International journal of environmental analytical chemistry》2013,93(9):663-675
From a viewpoint of physical and chemical form estimation, ultra-trace analytical techniques of nuclear materials in environmental samples for safeguards have been investigated at Japan Atomic Energy Research Institute. This article deals with (1) an outline of the developed techniques for bulk and particle analyses of uranium and plutonium in the safeguards environmental samples; (2) current R&D on techniques relating to estimation of the physical and chemical form, such as SEM images and EDX spectra for fine particles of nuclear materials and fission track observation applicable to fissile materials; and (3) possible analytical methodologies, as future works, applicable to ultra-trace amounts of nuclear materials in environmental samples. 相似文献
84.
Cesare Accinelli Anna Barra Caracciolo Paola Grenni 《International journal of environmental analytical chemistry》2013,93(8):579-587
Numerous studies have documented that a wide number of pharmaceuticals used in human and veterinary medicine have the potential to enter the aquatic ecosystem. The antiviral prodrug oseltamivir phosphate has received recent attention with regard to its possible use against the highly pathogenic H5N1 virus. This preliminary laboratory study investigated the persistence of the active antiviral drug, oseltamivir carboxylate (OSC), in water samples taken from an irrigation canal. After an initial rapid decrease, OSC concentrations slowly decreased during the remaining incubation period. Approximately 65% of the initial OSC amount remained in water at the end of the 36-day incubation period. A small amount of OSC was lost both from sterilized water and from sterilized water/sediment samples, suggesting a significant role for microbial degradation. Stimulating microbial processes by the addition of sediments resulted in reduced OSC persistence. Presence of OSC (1.5?µg?mL?1) did not significantly affect the metabolic potential of the water microbial population, estimated by glyphosate and metolachlor mineralization. In contrast, OSC caused an initial transient decrease in the size of the indigenous microbial population of water samples. 相似文献
85.
Branko Druzina Matej Stegu 《International journal of environmental analytical chemistry》2013,93(15):1079-1093
The degradation of 15 organophosphorus insecticides was studied in drinking, ground, and surface waters under different laboratory-controlled and environmental conditions. Surface waters originated from rivers Savinja (near the city of Celje) and Kamniska Bistrica (at the spring), which both belong to the Danube river basin. Groundwater was collected from wells (70?m deep) in Ljubljana, which are the direct source of drinking water for the capital. These matrices were selected on the basis of their different chemical composition and microbial activity. Major factors influencing the degradation were determined, such as temperature, oxygen, sunlight, pH, and type of water. The degradation of atrazine, present in many water sources in Slovenija, was followed simultaneously as a reference under the same conditions. The degradation kinetics was followed by gas chromatography with mass-selective detection, which also allowed the identification of some degradation by-products, such as oxon analogues paraoxon, dyfoxon, malaoxon, phenyl-methyl sulfoxide, fenthion sulfone, phorate sulfoxide, and phorate sulfone. The results show that the half-lives of the selected organophosphorus insecticides varied from 4 to 192 days or more, depending on the water source and experimental conditions. As a result, kinetically constants and half-lives were calculated for every tested insecticide, and major degradation products were determined. 相似文献
86.
Francesco Soggia Maria Luisa Abelmoschi Simona Dalla Riva Rodolfo De Pellegrini Roberto Frache 《International journal of environmental analytical chemistry》2013,93(4):367-378
Abstract The Project on an Antarctic Environmental Specimen Bank (Banca Campioni Ambientali Antartici—BCAA) began in 1994 in order to collect and classify samples from the Antarctic ecosystem to be used for future studies. The objectives of the project are similar to the general aims of the Environmental Specimen Banks, but they specifically focus on the chemical aspects concerning the research activities of the Italian Project on the “Micropollutants Chemistry” (Sector “Chemical Contamination” of the Italian Antarctic Research Programme—PNRA). During these first years the facilities suitable for storing a significant number of specimens (now over 2,000) at different temperatures (from ?30°C to ?150°C) and a database system, specifically designed for managing and consulting information concerning both the storage of samples and data on their chemical characterisation, have been developed. In addition, a programme for validating the procedures of Antarctic organisms storage by checking the stability of some chemical parameters both in fresh and freeze-dried specimens has been developed. 相似文献
87.
Paul P. Dillon Stephen J. Daly Anthony J. Killard Richard O'kennedy 《International journal of environmental analytical chemistry》2013,93(7-8):525-543
The interaction between antibody and antigen is characterised by relatively high affinity and specificity, making this type of reaction a prime candidate for use as an analytical tool. The interaction may be combined with biosensors in the production of immunosensors for environmental monitoring. Polyclonal and monoclonal antibodies have had a significant impact in analytical detection systems over the past few decades with antibody fragments becoming important in recent years. Production of antibodies to small haptens requires the initial conjugation of hapten to a larger carrier molecule. Once hapten-carrier conjugates have been produced, polyclonal, monoclonal and various antibody fragments may be produced by differing protocols. A critical step in the production of antibody fragments is the development of efficient screening procedures to identify suitable antibody-producing clones and this has been reviewed in this article. Various antibody types may then be used in the generation of immunosensors for the monitoring of environmental pollutants. The selection of the appropriate sensor technology applicable for the determination of an antibody-antigen interaction is of prime importance for immunosensor development. One example of such an application is surface plasmon resonance-based biosensors, as they provide real-time analysis of interactions between the antibody and antigen of interest. 相似文献
88.
Monitoring nitrite with optical sensing films 总被引:1,自引:0,他引:1
Ali A. EnsafiA. Kazemzadeh 《Microchemical Journal》2002,72(2):193-199
A new, low-cost nitrite sensor was developed by immobilizing a direct indicator dye in an optical sensing film for food and environmental monitoring. This sensor was fabricated by binding Safranine O to a cellulose acetate film that had previously been subjected to an exhaustive base hydrolysis. The membrane has good durability (>12 months) and a short response time (<8 s). Nitrite can be determined for the range of 0.005-2.00 μg ml−1 with 3δ detection limits of 0.001 μg ml−1. The method is easy to perform and uses acetylcellulose as a carrier. The reagents used for the activity of the cellulose support are inexpensive, non-toxic and widely available. 相似文献
89.
3-Amino-1,2,4-triazole (amitrole) is a widely used pesticide, with many difficulties to be analyzed at the regulatory level in drinking water, because its high solubility in water. This paper describes a simple and fast method for the simultaneous determination of amitrole and atrazin-2-hydroxy, principal degradation product of s-triazines, by capillary zone electrophoresis. Separation and determination of these herbicides in water samples was performed in 0.02 mol l−1 phosphate buffer at pH 3.2. The method allows determination of the amitrole and atrazin-2-hydroxy in water samples in concentration lower than 100 μg l−1. The detection limits using a previous preconcentration step of amitrole in Alberche River (Comunidad Autónoma de Madrid, Spain) and drinking water spiked samples was of 4 μg l−1. 相似文献
90.
Summary Procedures for the quantitative analysis of industrial effluents which involve concentration by solvent extraction or the
purge-and-trap method are time-consuming, labor-intensive, and prone to error. Direct aqueous injection gas chromatography
using an electron-capture detector for the analysis of volatile halocarbons at the ppb level is in routine use in many laboratories.
We now discuss the development of a similar protocol for the analysis of volatile polar organics such as acetone, methyl ethyl
ketone, methyl isobutyl ketone, and tretrahydrofuran using a flame-ionization detector. 相似文献