Bulat Kenessov

Al-Farabi Kazakh National University · Center of Physical-chemical Methods of Research and Analysis

This paper represents an improved method for on-site quantitation of benzene, toluene, ethylbenzene, and xylenes (BTEX) in atmospheric air using solid-phase microextraction (SPME) and portable gas chromatography with a split/splitless inlet and photoionization detector (GC-PID). The developed method includes air pumping to four replicate 250 mL gas...

12 Headspace solid-phase microextraction (HSSPME) of volatile organic compounds (VOCs) from 13 aqueous samples under vacuum conditions (Vac-HSSPME) allows increasing extraction rates and 14 decreasing detection limits compared to HSSPME under atmospheric pressure. The positive effect 15 of the vacuum on HSSPME of an analyte can be quickly estimated...

Headspace solid-phase microextraction (HSSPME) is one of the simplest and cost-efficient sample preparation approaches for determination of volatile organic compounds (VOCs) in soil. This study was aimed at the development of the model for numerical optimization of HSSPME of volatile organic compounds from dry soil samples by porous coatings using...

Headspace solid-phase microextraction (HSSPME) is one of the simplest and cost-efficient sample preparation approaches for determination of volatile organic compounds (VOCs) in soil. This study was aimed at the development of the model for numerical optimization of HSSPME of volatile organic compounds from dry soil samples by porous coatings using...

Soil is a primary sink and reservoir for pesticides pollution and one of the priority objects in terms of pesticides safety guidelines. Pesticides’ analysis in soil is a field of research which is in constant development facing numerous challenges such as increasing amount and variety of analytes and their combinations, as well as increasing demand...

This research was aimed at the development of the COMSOL Multiphysics® (CMP) model for simulating the headspace (HS) solid-phase microextraction (SPME) of volatile organic compounds (VOCs) from water using Carboxen/polydimethylsiloxane coating at 25°C. The developed model is mainly based on existing theory and previous research on the numerical mod...

Quantification of unsymmetrical dimethylhydrazine transformation products in solid samples is an important stage in monitoring of environmental pollution caused by heavy rockets launches. The new method for simultaneous quantification of unsymmetrical dimethylhydrazine transformation products in sand samples using vacuum-assisted headspace solid-ph...

A development of SPME-based analytical methods is a very time- and labor-consuming task. The finite element methods have found a wide application in SPME modeling for faster and more accurate optimization of analytical methods. In this work, a computational model for predicting the effect of temperature on extraction of VOCs from air onto SPME coat...

Air pollution is one of the main sources of risk to human health in the world [1]. Solid-phase microextraction (SPME) is a simpler alternative for complex and time-consuming methods, but still requires complex calibration procedures. Earlier, we proposed the simple and accurate method based on SPME and sampling in 20-mL vials for quantitation of be...

The development of new solid-phase microextraction coatings has attracted more attention due to a limited number of commercially available fibers and their inherent shortcomings, such as low effectiveness when extracting polar compounds, poor selectivity, and possible swelling upon exposure to certain solvents. In recent years, an increased interes...

Quantification of unsymmetrical dimethylhydrazine transformation products in ambient air is important for assessing environmental impact of heavy rockets’ launches. There are very little data of such analyses, which is mainly caused by the low number of analytes covered by the available analytical methods and their complexity. A simple and cost-eff...

Existing and newly developed technologies for clean-up of wastewaters and soils contaminated with rocket fuel unsymmetrical dimethylhydrazine (UDMH) are based on the oxidative treatment, as well as gasification in supercritical water. Being easily transformed by a radical mechanism, UDMH is capable of producing an extremely wide range of potentiall...

Solid-phase microextraction (SPME) fibers based on metal organic frameworks (MOFs) might be able to address some of the shortcomings of the existing commercial SPME fibers [1]. MOFs have permanent porosity with homogeneous structured nanoscale pores, high surface area (e.g. 7000 m2/g) [2], high mechanical and thermal stability (up to 500°C) [1] wit...

Quantification of unsymmetrical dimethylhydrazine (UDMH) transformation products (TPs) in solid samples is an important stage in monitoring environmental pollution by heavy rockets launches. Most prospective sample preparation methods for determination of UDMH TPs in soil samples are based on headspace solid-phase microextraction (HSSPME) [1]. Cond...

Quantification of unsymmetrical dimethylhydrazine (UDMH) transformation products (TPs) in solid samples is an important stage in monitoring of environmental pollution caused by heavy rockets launches. The new method for simultaneous quantification of UDMH TPs in sand samples using vacuum-assisted headspace solid-phase microextraction (Vac-HSSPME) f...

In this work, a green approach utilizing novel polymeric ionic liquid (PIL) coatings for headspace solid-phase microextraction (HS-SPME) of four current-use pesticides was studied for the first time. Epoxiconazole, fluroxypyr, metribuzin, and oxyfluorfen in soil were the target pesticides. Three PIL coatings containing 1-vinylbenzyl-3-hexadecylimid...

The air quality in cities in Kazakhstan has been poorly investigated despite the worsening conditions. This study evaluates national air pollution monitoring network data (Total Suspended Particle-TSP, NO2, SO2, and O3) from Kazakhstan cities and provides estimates of excess mortality rates associated with PM2.5 exposure using the Global Exposure M...

Number of cities worlwide experienced air quality improvements during COVID-19 lockdowns; however, such changes may have been different in places with major contributions from nontraffic related sources. In Almaty, a city-scale quarantine came into force on March 19, 2020, which was a week after the first COVID-19 case was registered in Kazakhstan....

In this study, spatial and temporal patterns of PM10, PM2.5, NO2, SO2, and CO in Almaty, the largest city of Kazakhstan, in the period between 2013 and 2018 are explored. Severe degradation of air quality was observed from the data that have been used in this study. Annual averages of PM2.5, PM10, and NO2 concentrations exceeded the WHO annual limi...

Air quality in Kazakhstan cities has been poorly investigated despite their deteriorating situations. This study evaluates the national air pollution monitoring network data (PM 10, NO2, SO2, and O3) in Kazakhstan cities, and provides the estimates of excess mortality rates associated with PM 2.5 exposure using the Global Exposure Mortality Model (...

Current standard approaches for quantitation of volatile organic compounds (VOCs) in outdoor air are labor-intensive and/or require additional equipment. Solid-phase microextraction (SPME) is a simpler alternative, however, its application is often limited by complex calibration, the need for highly pure gases and the lack of automation. Earlier, w...

Experimental optimization of analytical methods based on solid-phase microextraction (SPME) is a complex and labor-intensive process associated with uncertainties. Using theoretical basics of SPME and finite element analysis software for the optimization proved to be an efficient alternative. In this study, an improved finite element analysis-based...

Existing methods for cleanup of wastewaters and soils polluted with the extremely toxic rocket fuel unsymmetrical dimethylhydrazine (UDMH) are mainly based on the treatment with various oxidative reagents. Until now, the assessment of their effectiveness was based on the residual content of UDMH and did not take into account the possibility of the...

Measuring concentrations of unsymmetrical dimethylhydrazine (UDMH) transformation products (TPs) in air is important for assessing environmental and human health impact of heavy rockets’ launches. However, there are very little data of such analyses, which is mainly caused by complexity and low number of analytes covered by available analytical met...

Contamination of soil by heavy metals is among the important environmental problems due to their toxicity and negative impact to human health and the environment. An effective method for cleaning the soil from heavy metals is phytoremediation using the second-generation bioenergy species Miscanthus × giganteus. The purpose of this research is to st...

Vacuum-assisted headspace solid-phase microextraction (Vac-HSSPME) is an emerging analytical technique, which further advances HSSPME by providing lower detection limits of analytes with poor volatility at shorter extraction times. This review discusses the theoretical aspects and possibilities of the Vac-HSSPME technique for analysis of environmen...

Finding farm-proven, robust sampling technologies for measurement of odorous volatile organic compounds (VOCs) and evaluating the mitigation of nuisance emissions continues to be a challenge. The objective of this research was to develop a new method for quantification of odorous VOCs in air using time-weighted average (TWA) sampling. The main goal...

Determination of time-weighted average (TWA) concentrations of volatile organic compounds (VOCs) in air using solid-phase microextraction (SPME) is advantageous over other sampling techniques, but is often characterized by insufficient accuracies, particularly at longer sampling times. Experimental investigation of this issue and disclosing the ori...

Determination of transformation products (TPs) of rocket fuel unsymmetrical dimethylhydrazine (UDMH) in soil is highly important for environmental impact assessment of the launches of heavy space rockets from Kazakhstan, Russia, China and India. The method based on headspace solid-phase microextraction (HS SPME) and gas chromatography-mass spectrom...

Quantification of transformation products of unsymmetrical dimethylhydrazine (UDMH) in soil requires tedious, time- and labor-consuming sample preparation. The simple and fast method for quantification of transformation products of UDMH in aqueous extracts from soil using vacuum-assisted headspace solid-phase microextraction (Vac-HSSPME) was optimi...

Development of simple, fast and accurate methods for quantification of volatile organic compounds (VOCs) in soil samples is important for providing greater efficiency of analytical laboratories in Kazakhstan and other developing countries. Naphthalene is a model polycyclic aromatic hydrocarbon (PAH), belonging to a group of compounds of significant...

A new, sensitive and simple method based on vacuum-assisted headspace solid-phase microextraction (Vac-HSSPME) followed by gas chromatography-mass-spectrometry (GC-MS), is proposed for the quantification of rocket fuel unsymmetrical dimethylhydrazine (UDMH) transformation products in water samples. The target transformation products were: pyrazine,...

Optimization of analytical methods based on solid-phase microextraction (SPME) using numerical modelling has many advantages including better precision, time and cost efficiency [1]. Effects of numerous extraction parameters can be quickly predicted, which simplifies a method development. Numerical simulation using COMSOL Multiphysics allowed disco...

Urban air pollution with benzene, toluene, ethyl benzene and xylenes (BTEX) is a common phenomenon in major cities where the pollution mainly originates from traffic as well as from residential heating. An attempt to rank cities according to their BTEX air pollution is not necessarily straight forward as we are faced with several individual polluta...

There is a great demand for simple, fast and accurate methods for quantification of volatile organic contaminants in soil samples. Solid-phase microextraction (SPME) has a huge potential for this purpose, but its application is limited by insufficient accuracy caused by a matrix effect. The aim of this research was to develop the method for BTEX qu...

Exhaust gases from internal combustion engines are the main source of urban air pollution. Quantification of PAHs in the exhaust gases is needed for emissions monitoring, enforcement, development, and testing of control technologies. The objective was to develop quantification of gaseous naphthalene in diesel engine exhaust based on diffusion-contr...

Quantification of trace concentrations of transformation products of rocket fuel unsymmetrical dimethylhydrazine (UDMH) in water requires complex analytical instrumentation and tedious sample preparation. The goal of this research was to develop the simple and automated method for sensitive quantification of UDMH transformation products in water us...

Parameters of headspace solid-phase microextraction, such as fiber coating (85 μm CAR/PDMS), extraction time (2 min for white and 3 min for red wines), temperature (85 °C), pre-incubation time (15 min) were optimized for identification and quantification of semi-volatile additives (propylene glycol, sorbic and benzoic acids) in wines. To overcome p...

This review explores the current state-of-the-art and progress towards on-site quantification of organic pollutants in soils with solid-phase microextraction (SPME). In spite of many available methods, only few publications report on-site analyses of soil samples by SPME. To date, the only application of SPME for the on-site quantification of organ...

Free download link (works till May, 13) - http://authors.elsevier.com/a/1SlqK94qqmsBZ Benzene, toluene, ethylbenzene and xylenes (BTEX) comprise one of the most ubiquitous and hazardous groups of ambient air pollutants of concern. Application of standard analytical methods for quantification of BTEX is limited by the complexity of sampling and samp...

BTEX (benzene, toluene, ethylbenzene, xylene) is one of the most dangerous groups of organic toxicants in terms of emissions and risks to public health. BTEX are present in almost all technogenic and natural objects. The greatest risk to public health is caused by BTEX contamination of cities characterized by high population densities and emissions...

This study explored the possibility of applying different carbon-based adsorbents for removal of benzene, toluene, ethylbenzene and o-xylene (BTEX) from indoor air in static and dynamic modes. To determine BTEX removal effectiveness, the approach based on solid-phase microextraction (SPME) in combination with gas chromatography – mass spectrometry...

Concentrations of selected organochlorine pesticides (OCPs), i.e., 4,4ʹ-dichlorodiphenyltrichloroethane (p,pʹ-DDT), its metabolites (p,pʹ-DDE, p,pʹ-DDD), and hexachlorocyclohexanes (HCHs), have been determined in 100 soil samples collected from a contaminated site centered around a former storehouse in the Kyzyl Kairat village, Almaty region, Kazak...

1-Methyl-1H-1,2,4-triazole (MTA) is the most stable and abundant transformation product of dimethylhydrazine-based rocket fuel. Concentrations of MTA in soils affected by rocket fuel spills are regularly monitored using a number of available methods mainly based on GC–MS. Complex, time and labor intensive sample preparation makes quantification of...

Phenol is a toxic environmental pollutant possessing carcinogenic and mutagenic properties. Determination of phenol in soil by certified methods requires long and laborious sample preparation. Solid-phase microextraction (SPME) allows much simpler and faster determination of pollutants in soils. However, method accuracy is limited by the problem of...

Most rockets of middle and heavy class launched from Kazakhstan, Russia, China and other countries still use highly toxic unsymmetrical dimethylhydrazine (UDMH) as a liquid propellant. Study of migration, distribution and accumulation of UDMH transformation products in environment and human health impact assessment of space rocket activity are curr...

Kazakhstan is a home of the largest cosmodrome in the world - Baikonur. Analysis of soil samples contaminated by rocket fuel unsymmetrical dimethylhydrazine (UDMH) and its transformation products is always completed in laboratories located hundreds to thousands of kilometers from sampling locations. Solid-phase microextraction (SPME) provides simpl...

Environmental monitoring of Central Kazakhstan territories where heavy space booster rockets land requires fast, efficient, and inexpensive analytical methods. The goal of this study was to develop a method for quantitation of the most stable transformation product of rocket fuel, i.e., highly toxic unsymmetrical dimethylhydrazine – 1-methyl-1H-1,2...

A new and simple method for benzene, toluene, ethylbenzene and o-xylene (BTEX) quantification in vehicle exhaust was developed based on diffusion-controlled extraction onto a retracted solid-phase microextraction (SPME) fiber coating. The rationale was to develop a method based on existing and proven SPME technology that is feasible for field adapt...

Oxidation ofunsymmetrical dimethylhydrazine(UDMH) during a wa-ter treatment has several disadvantages including formation of stable toxic byproducts. Effectiveness of treatment methods in relation to UDMHtrans-formation products is currently poorly studied. This work considers the effectiveness of chemical oxidants in respect to main metabolites of...

The article represents new method for discovery of adulterated cognacs and brandies based on solid-phase microextraction (SPME) in combination with gas chromatography – mass spectrometry (GC-MS). The work comprised optimization of SPME parameters (extraction temperature and time, concentration of added salt) with subsequent analysis of authentic sa...

1,1-Dimethylhydrazine (1,1-DMH) used as a rocket fuel component is highly reactive and unstable compound. It greatly complicates its accurate and express determination in environmental samples. Goal of this work was to develop a method for its express determination in water samples based on solid-phase microextraction with preliminary derivatizatio...

Detection of trace amounts of organochlorine pesticides in food (ng/kg) is very complex and expensive. Therefore, development of highly sensitive and inexpensive methods is of a high importance. The current study is devoted to the development of inexpensive method for sample preparation and highly sensitive determination of organochlorine pesticide...

Screening of toxic polycyclic aromatic hydrocarbons (PAHs) plays very important role allowing to determine the nature and sources of pollutants into the environment. The aim of this work was to develop a screening method of PAHs in air of Almaty by gas chromatography-mass spectrometry (GC-MS) in combination with solid-phase microextraction (SPME)....

Transformation products (TPs) of 1,1-dimethylhydrazine (DMH), a highly toxic and reactive rocket fuel, are of huge fundamental and practical interest to scientists working in the field of chemical transformations in the environment. Due to the high reactivity of 1,1-DMH, its transformation occurs in a series of chemical reactions. This chapter desc...

The chemical or microbiological degradation or transformation of the primary pollutant may lead to a series of transformation products (TPs) that may well constitute an additional environmental and human health risk to that posed by the primary pollutant. The environmental pollution by rocket fuel residues following launches of heavy rocket carrier...

Main methods of soil treatment used in contamination by 1,1-dimethylhydrazine were considered in this paper. It was noted that during cleaning soils contaminated by propellants the content transformation products of 1,1-dimethylhydrazine is not considered, while they are not less dangerous pollutants. Thermal treatment of soil contaminated by main...

An analytical method for determination of volatile organic compounds (VOCs) in Kazakhstan red wine was developed in this study. The volatile composition of red wine was determined by headspace SPME in combination with GC-MS. The DVB/CAR/PDMS fiber and the sample volume of 10 mL were chosen. The optimal conditions for HS-SPME were temperature of 30°...

Adulteration of alcoholic beverages in Kazakhstan and many developing countries around the world is a wide-spread problem causing health risks to population. For law enforcement agencies, forensic examination of actual products is generally the only tool to obtain proper evidence against responsible individuals and companies. Solid-phase microextra...

Headspace solid phase microextraction (HS-SPME) in combination with gas chromatography and mass-spectrometry (GC/MS) was studied for analysis of water samples. The organochlorine pesticides (OCPs), p,p'-DDT, p,p'-DDD, and p,p'-DDE were collected and analyzed by GC/MS. To select of effective fiber coatings four types of SPME fibers were examined and...

The air quality of Almaty, the largest city in Kazakhstan, has been assessed applying the DPSIR (Driving forces, Pressures, Sate, Impacts, Responses) approach as overall framework. The paper focuses on the traffic component that is responsible for approx. 80% of the air pollution in the city. Further factors comprise power plants, minor industrial...

Present paper describes optimization of the method of quantitative determination of total petroleum hydrocarbons in soil samples using headspace solid - phase microextraction (SPME) in combination with gas chromatography - mass spectrometry (GC-MS). Effects of moisture content and solvent additives were studied. It was established that an increase...

Determination of total petroleum hydrocarbons (TPH) in water is an important tool for monitoring of contamination due to oil spills or leaking storage tanks. In this study, a screening method for the quantification of total petroleum hydrocarbons in water based on solid phase microextraction (SPME) in combination with gas chromatography - mass spec...

The paper represents a review of the actual directions in study of ecological consequences of highly toxic 1,1-dimethylhydrazine-based rocket fuel spills. Recent results on study of processes of transformation of 1,1-dimethylhydrazine, identification of its main metabolites and development of analytical methods for their determination are generaliz...

In our research, three fall places of first stages of Proton rockets have been studied for the presence and distribution of transformation products of 1,1-dimethylhydrazine (1,1-DMH). Results of identification of transformation products of 1,1-DMH in real soil samples polluted due to rocket fuel spills allowed to detect 18 earlier unknown metabolit...

Formaldehyde dimethylhydrazone (FADMH) is one of the important transformation products of residual rocket fuel 1,1-dimethylhydrazine (1,1-DMH). Thus, recent studies show that FADMH toxicity is comparable to that of undecomposed 1,1-DMH. In this study, a new method for quantification of FADMH in water based on solid phase microextraction (SPME) in c...

В работе предложена система аналитического контроля объектов окружающей среды на местах проливов гидразиновых ракетных топлив. Основой всей системы является методика скрининга продуктов трансформации 1,1-диметилгидразина, позволяющая собрать исчерпывающее количество данных с минимальными временными и трудозатратами. Также особенностью системы являе...

The paper describes a novel SPME-based approach for sampling and analysis of transformation products of highly reactive and toxic unsymmetrical dimethylhydrazine (UDMH) which is used as a fuel in many Russian, European, Indian, and Chinese heavy cargo carrier rockets. The effects of several parameters were studied to optimize analyte recovery. It w...

The mutagenic effect of the rocket fuel 1,1-dimethyl hydrazine has been studied experimentally and compared to the well-recognized mutagene N-nitroso dimethylamine. The manifestation of the effect for both compounds was disclosed through a significant increase in the chromosome aberration frequency in the bone marrow cells of intoxicated rats. The...

A paper describes a method for determination of N-nitrosodimethylamine in water, polluted by spills of 1,1-dimethylhydrazine, based on solid phase microextraction coupled to gas chromatography/mass spectrometry. A method detection limit was determined to be 1 ug/kg, relative error was below 20%. A method is very sensitive and selective as well as q...

1,1-Dimethylhydrazine (1,1-DMH) transformation processes in water in the presence of iron (III), copper (II) and manganese (II) cations were studied using the methods of high-performance liquid chromatography (HPLC) and solid-phase microextractinom in combination with gas chromatography - mass spectrometry (SPME-GC-MS). It is established that the p...

The possible impact of the rocket fuel 1,1-dimethyl hydrazine (heptyl) (1) and its transformation products on human health has been studied using (Quantitative) Structure Activity/Toxicity ((Q)SAR/(Q)STR) modelling, including both ADME models and models for acute toxicity, organ specific adverse haematological effects, the cardiovascular and gastro...