Визначення триазолів при застосуванні сумішевих фунгіцидних препаратів на їх основі

Owing to their widespread use in agriculture and urban weed control and because of their high mobility in the subsoil, polar pesticides such as phenoxy acids and other acidic pesticides have been especially considered as a potential source of groundwater contamination. In Europe, pesticide residues tolerances in drinking water were set by the European Union Commission to 100 ng L−1for an individual compound and 500 ng L−1for the sum of pesticide residues. These maximum tolerances constitute a real challenge to analysts working in the field of pesticide residue monitoring. In the following article, analytical methods for the multiresidue analysis of phenoxy acids and other acidic pesticides in environmental samples at trace level concentrations are presented. Analytical methods using capillary gas chromatography (GC), high‐performance liquid chromatography (HPLC), capillary zone electrophoresis (CZE) and automated multiple development thin‐layer chromatography (AMDTLC) are described. GC methods are most often used in routine analysis of acidic pesticides owing to their unrivaled advantages in separation power. GC methods can be used in multiresidue analysis of up to more than 50 analytes at trace level concentrations. Owing to their high polarity and low volatility, acidic pesticides are not directly amenable to GC analysis, thus suitable derivatization methods are required. The applicability and drawbacks of several derivatization methods are described in detail. GC can be used with various detection methods such as electron capture detection (ECD), nitrogen–phosphorus detection (NPD), atomic emission detection (AED) or mass spectrometry (MS). GC/MS (gas chromatography/mass spectrometry) or GC/MS/MS (tandem mass spectrometry) detection provides the highest possible level of confidence independent of the complexity of the environmental matrix from water or even soil samples. The highest selectivity and sensitivity is achieved in selected ion monitoring (SIM) or in selected reaction monitoring (SRM) mode. Progress in coupling of HPLC to MS has improved the possibilities of identification and confirmation of analytes at trace level concentrations using HPLC methods and new promising analytical approaches such as HPLC coupled to atmospheric pressure ionization (API) MS/MS will gain much importance in the future. Enantioselective separation of different chiral isomers of phenoxy acid pesticides can be achieved applying CZE or by applying GC or HPLC with special chiral phases.In water analysis, conventional liquid–liquid extraction (LLE) has mostly been replaced by solid‐phase extraction (SPE) methods to extract and enrich the analytes from the samples. Two standard operating procedures (SOPs) are presented as examples for the analysis of phenoxy acids and other acidic pesticides in environmental samples (water and soil). Detection limits down to the low nanogram per liter level or down to the low microgram per kilogram level can be achieved for water samples or soil samples, respectively. Several examples for the environmental analysis of actual samples show the performance and sensitivity of today's trace level multiresidue analysis.

The synthetic cannabinoids 5F-QUPIC and MDMB-CHMICA were sprayed on plant material intended for smoking and was seized as a criminal evidence. Their presence was confirmed by gas chromatography – mass spectrometry (GC-MS), and nuclear magnetic resonance (NMR). In the absence of analytical standards (indirect approach), the quantity of 5F-QUPIC in the herbal extract was determined by high-performance liquid chromatography with diode array detection (HPLC-DAD) based on total hydrolysis and measurement of the hydrolytic product (8-hydroxyquinoline) at 292 nm. The quantity of MDMB-CHMICA was determined using the ratio of 1H-NMR signals of both compounds in methanol-d4. 5F-QUPIC and MDMB-CHMICA in the herbal mixture were determined by the validated HPLC-DAD protocol by a direct approach with standards.

Investigations on insoluble dietary fibre (IDF) of wheat, rye, barley, oat, maize, rice and millet led to the identification of several new dehydrodimers of ferulic acid (DFA). These compounds arise from 8–8′, 8–5′, 8–O–4′ and 5–5′ coupling. Esterified phenolics were set free by mild alkali hydrolysis, total amounts of phenolics (ester- plus etherified) were determined by alkali hydrolysis under pressure. Phenolic acids were analysed by gas chromatography – mass spectrometry (GC-MS) as their trimethylsilyl (TMS) derivatives and by high performance liquid chromatography – diode array detection (HPLC-DAD). In esterified form 8–8′aryl DFA and 5–5′ DFA dominate in most cereal IDF with, together, 45–60% of the DFA sum. More than 60% of total bound DFA are involved in ether linkages. Highest amounts of esterified as well as etherified DFA are estimated in millet, followed by maize. DFA contents of wheat, rye and barley are about two- to threefold lower than in millet but about twofold higher than in oat or rice.

Postmortem toxicology is a unique application of forensic toxicology to investigate whether or not drugs or poisons contribute to the cause and manner of death. Virtually, all body parts of the deceased can be used for toxicological analysis, but the quality and availability of specimens is often affected by postmortem degradation or autolysis. An overview on the significance of different body fluids, tissues, and specimens are given. While the most common specimens of choice are blood, urine, and vitreous humor, depending on the case and availability of specimens for collection, liver, gastric content, etc. are also useful. Additional information relevant to the case, such as evidence collected at the scene, medical history, and autopsy findings, can assist in determining the appropriate toxicological analysis and to assist in the interpretation of results. Using a single analytical method for the analysis of all potential drugs and poisons with distinct chemical and physical properties is practically impossible. A typical toxicological examination usually consists of a general toxicological screening scheme and supplemented with case‐specific tests. A combination of chromatographic techniques (gas chromatography (GC) and high‐performance liquid chromatography (HPLC)) with various detection systems (nitrogen‐phosphorus, electron capture, and mass spectrometry (MS) for GC; diode‐array detector (DAD) for HPLC) are useful to provide diverse screening and analytical capabilities. Liquid‐liquid extraction and solid‐phase extraction are common extraction techniques used prior to chromatographic analysis. The application of liquid chromatography mass spectrometry (LC‐MS) has been demonstrated to be a useful complimentary technique for the analysis of those substances that are not amenable to gas chromatography mass spectrometry (GC‐MS) and high‐performance liquid chromatography diode‐array detector (HPLC‐DAD). Recent developments in the application of hybrid linear ion‐trap liquid chromatography tandem mass spectrometry (LC‐MS/MS) and LC‐time‐of‐flight‐MS have successfully demonstrated their potential use in general unknown screening. When drugs and poisons are detected, confirmation tests and, if necessary, quantitative analyses will have to be performed. To ensure the accuracy and reliability of the toxicological results, analytical methods must be properly validated.

Four urea herbicides, isoproturon, chlorotoluron, linuron and diuron, were determined by gas chromatography (GC) with a nitrogen–phosphorus detector (NPD) after derivatization, with detection limits of 0.035, 0.039, 0.041 and 0.036 µg l–1, respectively. The concentrations of all analytes were linear over the range 0.1–8.0 µg l–1, with recoveries in excess of 75% from spiked potable waters. In their standard, underivatized form the herbicides were found to be thermally unstable on passage through a GC column. After derivatization, by methylation using iodomethane and a strong base, the resulting compounds were found to be stable at elevated temperatures, and so could be determined by GC. The derivatized herbicides were also analysed by GC–mass spectrometry, in order to elucidate the structures of the derivatized compounds. Each compound yielded a different product with a different retention time. The reaction was of the type typical of nucleophilic displacement, with the methyl group attacking the nitrogen of the amide group, forming a stable tertiary amide and hydrogen iodide gas. This method was found to be more selective than the Standing Committee of Analysts' method owing to the nature of the analysis. Firstly, GC, compared with high-performance liquid chromatography, offers better resolution. There are many ultraviolet absorbers in water which can be detected by the standard method, but use of a specific detector, such as an NPD, offers better selectivity. The method was also applied to other urea herbicides, including monuron, methabenzthiazuron and tebuthiuron, which were also successfully determined, although no quantitative data have been obtained.

A new and effective high performance liquid chromatography (HPLC) method was developed for fast quantification of phenylethyl alcohol in rose water. Chemical profiles of rose water and oil of Rosa damascena and Rosa rugosa from Southeast China were investigated by gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS). Fast HPLC was achieved by rapid sample preparation and fast elution using acetonitrile–water (35:65, v/v) on Zorbax SB-C18. It was validated and applied to rapid analysis of different rose water samples, in which the contents of phenylethyl alcohol ranged from 454.6 to 526.7 µg/mL. GC and GC–MS revealed that rose water volatiles of R. damascena and R. rugosa mainly consisted of phenylethyl alcohol (90.2% and 78.7%, respectively) and citronellol (4.5% and 13.5%, respectively). This is the first report on fast HPLC quantification of phenylethyl alcohol in rose water and chemical profiles of rose water volatiles of R. damascena and R. rugosa from Southeast China. The developed HPLC method can serve as a fast quality control during rose water production.

High performance liquid chromatography in pharmaceutical analyses

Organochlorine (OC) pesticides is a general term for a broad class of compounds including some well‐known compounds such as dichlorodiphenyltrichloroethane (DDT), lindane, dieldrin, endrin, heptachlor epoxide (HEPO), endosulfan, and chlordane. OC pesticides are the first class of compounds introduced in agricultural and civil uses to counteract noxious insects and insect‐borne diseases. In general they are lipophilic compounds with noticeable chemical and environmental stability. Although most OC pesticides have been progressively restricted and then banned in the 1970s in most industrialized countries, a widespread environmental pollution has resulted from their use in agriculture and civil uses.Pyrethrins are natural insecticidal compounds found in the extract of pyrethrum flowers. Also, a number of pesticides have been synthesized that share the biologically relevant chemical moiety with the pyrethrins and are referred to as pyrethroids (PYR). These compounds possess equal or better biological activity and better chemical stability that allow their use in agriculture, husbandry, and civil applications. Both OC and PYR pesticides can occur in fruits and vegetables as well as in food of animal origin and environment. The levels can be different as a result of direct application or indirect contamination. Such different matrices and levels of contamination require different analytical approaches and resources.A review is presented of the array of the analytical techniques most frequently applied for the extraction, cleanup and identification/determination. Extraction techniques include solvent extraction, supercritical fluid extraction (SFE), solid‐phase extraction (SPE), and solid‐phase microextraction (SPME). Solvent extraction is carried out in different ways depending on the type of matrix (fatty and nonfatty samples, soil, sediments, and water), such as Soxhlet, liquid–liquid extraction (LLE), pressurized liquid extraction (PLE), and matrix solid‐phase dispersion (MSPD).Different cleanup techniques are presented that can be applied to fatty and nonfatty samples. They include liquid– liquid partitioning (LLP), size‐exclusion chromatography (SEC), sweep codistillation and assisted distillation, column adsorption chromatography, chromatography on SPE cartridges, high‐performance liquid chromatography (HPLC), thin‐layer chromatography (TLC) and degradative cleanup. The techniques are presented as modular steps that can be arranged in different ways to cope with cleanup requirements posed by different sample composition and different selectivity/sensitivity of the identification/determinative techniques. The performances of the cleanup steps are discussed in terms of matrix removal and amount of sample that can be handled. Also the possibilities of linking different steps and the chance for automation of the cleanup process are indicated. Some environmental pollutants, such as polychlorinated biphenyl (PCB), have similar analytical behavior to some OC pesticides and can occur in the same environmental matrices. Some cleanup steps useful for the group separation of PCB and OC pesticides are presented.The techniques for identification and determination include gas chromatography (GC) with selective detectors, HPLC, and their combination with mass spectrometry (MS). The importance of the combination of responses from different analytical techniques to obtain reliable identification at trace levels is underlined.

Chapter 16 Pharmaceuticals

New sensitive and specific analytical methods are needed for the analysis of sesamin, asarinin, and sesamolin in sesame seed oils, sesame dietary supplements, as well as in serum samples from clinical studies involving sesamin, asarinin, and sesamolin. The objective of this study was to develop a high performance liquid chromatographic (HPLC) method with photodiode array and fluorescent detectors and a gas chromatography mass‐spectrometry (GC/MS) method for the analysis of sesamin, asarinin (episesamin), and sesamolin in sesame oil and in serum samples. Sesame oil samples were extracted with methanol whereas the serum samples were extracted with ethyl acetate or n‐hexane. The individual lignans were analyzed by HPLC using reversed phase C18 columns. Analytical recoveries of sesamin, asarinin, and sesamolin from sesame oil were 92–94 % with two extractions. Recoveries from serum ranged from 87 to 97 %. The limit of quantitation with the fluorometric detector was 0.1 ng compared to 0.1 μg with the PDA detector. The concentrations of sesamin, asarinin, and sesamolin in Orchids and Sigma sesame oil were 0.4, 0, and 0.15 % and 0.19, 0.09, and 0 %, respectively. The identities of the individual lignans obtained by HPLC were confirmed by GC/MS and the concentrations of sesamin, asarinin, and sesamolin obtained with the fluorometric detector correlated with those obtained by GC/MS (r2 = 0.94, P < 0.001). The HPLC and GC/MS methods permit simple and efficient procedures for the analysis of sesamin, asarinin, and sesamolin in sesame oil samples as well as in serum samples.

Waste water from ammunition production sites and aqueous samples (ground and surface water) on or near former military sites on which explosives were produced or filled, e.g. into shells, may be contaminated by the original explosives—mainly nitrotoluenes (such as dinitrotoluenes, trinitrotoluene (TNT)) and nitramines (such as hexogen (RDX), octogen (HMX), and tetryl) or hexyl, but also by byproducts and compounds formed by biodegradation of the explosives such as aminonitrotoluenes, chlorinated nitrobenzenes and nitrophenols. These compounds can be extracted from aqueous samples by liquid/liquid extraction (using dichloromethane or toluene) or by solid phase extraction using C‐18 adsorbents with high recoveries (usually ≥85%) provided they contain only one amino group. Nitrotoluenes, chlorinated nitrobenzenes and aminonitrotoluenes (nitrotoluidines) may be determined by gas chromatography (GC) using selective detectors such as an electron capture detector (ECD), a nitrogen‐phosphorus detector (NPD) or a chemiluminescence detector (thermal energy analyzer, TEA). The use of combined gas chromatography/mass spectrometry (GC/MS) under electron impact conditions is even more specific. Detection limits comparable to an ECD or NPD, however, are only achieved if the mass spectrometer is operated under selected ion monitoring (SIM). Nitrophenols are derivatized after extraction by heptafluorobutyric anhydride or by acetic anhydride where the latter method can be directly applied to the aqueous sample. The nitramine explosives, such as RDX, HMX, and tetryl, hexyl, the nitrate esters, such as nitropenta (PETN) and nitroguanidine as well as picric acid cannot, or only with difficulty, be analyzed by gas chromatography. They may be determined by high performance liquid chromatography (HPLC) with UV‐detection. The HPLC analysis can be extended to include also nitrotoluenes and nitroaminotoluenes.

High-performance liquid chromatographic separation of monosaccharides as their peracetylated ketoximes and aldononitriles

Introduction Cladonia rangiformis, also known as reindeer lichen, has been used for various remedies in folk medicine. The rich nutritional value of this lichen is reflected in the fact that it contains atranorin, which has been proven to have numerous biological activities. Objective The chemical composition, antioxidant, anticholinesterase, and antigenotoxic activities of the C. rangiformis acetone extract were investigated. The novelty of this work is that anticholinesterase activity, protective effect on human lymphocytes, and antioxidant activity by the cupric-reducing antioxidant capacity (CUPRAC) method of C. rangiformis extract were determined for the first time, as well as gas chromatography - mass spectrometry (GC-MS) profile. Methods Chemical composition was carried out by high-performance liquid chromatography (HPLC)-diode array detector and GC-MS. Antigenotoxic effect was evaluated in human lymphocytes by cytokinesis-block micronucleus assay. Total phenolic content, DPPH and ABTS radical scavenging capacities, CUPRAC, and total reducing power were determined spectrophotometrically. Determination of acetylcholinesterase activity was performed by Ellman's colorimetry assay. The statistical analysis of variance (One-way ANOVA) was performed using Origin software package version 7.0. Results HPLC method was used to identified 3 compounds with atranorin as predominant constituent (97.2%). Fumarprotocetraric and atraric acid were represented in a much smaller mutually approximate amount, 0.3 and 0.5%, respectively. Rangiformic acid was the most abundant volatile compound. Acetone extract of C. rangiformis (2 μg/mL) decreased the frequency of micronuclei by 15.5% while the radioprotectant amifostine reduced the frequency of occurrence of micronuclei by 11.4%. On the contrary, at a concentration of 1.0 mg/mL the extract exhibited an activating effect on cholinesterase (2.0%), while at a concentration of 10.0 mg/mL it showed a weak inhibitory effect (7.3%). The total phenol content was 132.71 μg gallic acid equivalents per mg of dry extract. The IC50 value for the DPPH experiment was 16.19 mg/mL and for ABTS was 11.80 mg/mL. Cupric reducing capacity and total reducing power were 17.81 μg Trolox equivalents per mg of dry extract and 0.45 μg ascorbic acid equivalents per mg of dry extract, respectively. Conclusion In addition to previously identified compounds in the acetone extract, atraric acid was identified for the first time by using HPLC method, and orcinol, β-orcinol, lauric alcohol, atranol, and rangiformic acid by using GC-MS method. The results of biological activity proved that acetone extract had antioxidant capacity and weak anticholinesterase activity. Reduction of the number of micronuclei in human lymphocytes, classified C. rangiformis as promising substances source with beneficial effects on DNA damage.

Diphenamide, napropamide and metolachlor (FIG. 1) are selective, pre-emergence arylamide herbicides used to control the growth of annual grasses and broadleaf weeds in a variety of fields, e.g. fruit trees, nuts, corns, green crops, etc. They possess high activity and moderate toxicity. For food and environment safety, the detailed investigations on their residues and metabolism are very important. Diphenamide, napropamide and metolachlor in the pesticide products, serum, urine, soil, environmental water, fruits and wine have been widely analyzed by ELISA, fluorescence, phosphorescence, capillary electrophoresis, high performance liquid chromatography (HPLC), gas chromatography(GC) and GC mass spectrometry (GC-MS). However, to our knowledge, simultaneous residue analysis of diphenamide, napropamide and metolachlor in tobacco samples has not been extensively documented. Tobacco is greatly consumed by smokers throughout the world. The pesticide residue in tobaccos might be potentially harmful to smokers' health. With this in mind the residue determination and control of diphenamide, napropamide and metolachlor in the tobacco leaves are very important for tobacco products and consumers. For these three herbicides, the tolerable maximum residue limits (MRLs) have been limited ranging from 0.05 (for tobacco products) to 5 mg/kg (for tobacco leaves) in different European countries. For the complex tobacco samples, the GC and HPLC with UV detection suffer from matrix interference making quantification and identification of these herbicides difficult. In such cases the removal of the matrix effects and identification of the target compounds are of great importance. The present work reports the extraction and clean up procedures, as well as, the chromatographic conditions developed for the simultaneous determination of diphenamide, napropamide and metolachlor residues in the fluecured tobacco leaves, from the different sources using HPLC-UV method.

Determination of urinary and salivary cotinine using gas and liquid chromatography and enzyme-linked immunosorbent assay