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1.
Sci Total Environ ; 927: 172215, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38580117

ABSTRACT

Water pollution has become a critical global concern requiring effective monitoring techniques and robust protection strategies. Contaminants of emerging concern (CECs) are increasingly detected in various water sources, with their harmful effects on humans and ecosystems continually evolving. Based on literature reports highlighting the promising sorption properties of metal-organic frameworks (MOFs), the aim of this study was to evaluate the suitability of NH2-MIL-125 (Ti) and UiO-66 (Ce) as sorbents in passive sampling devices (MOFs-PSDs) for the collection and extraction of a wide group of CECs. Solvothermal methods were used to synthesize MOFs, and the characterization of the obtained materials was performed using field-emission scanning electron microscopy (FE-SEM), powder X-ray diffractometry (pXRD) and Fourier-transform infrared (FTIR) spectroscopy. The research demonstrated the sorption capabilities of the tested MOFs, the ease and rapidity of their chemical regeneration and the possibility of reuse as sorbents. Using chemometric analysis, the structural properties of CECs determining the sorption efficiency on the surface of NH2-MIL-125 (Ti) were identified. The MOFs-PSDs were lab-calibrated to examine the kinetics of analytes sorption and determine the sampling rates (Rs). MOFs-PSDs and CNTs-PSDs (PSDs containing carbon nanotubes as a sorbent) were then placed in the Elblag River and the Vistula Lagoon to sampling and extraction of the target compounds from the water. CNTs-PSDs were selected, based on our previous research, for the comparison of the effectiveness of the MOFs-PSDs in environmental monitoring. MOFs-PSDs were successfully used in monitoring of CECs in water. The time-weighted average concentrations (CTWA) of 2-hydroxycarbamazepine, carbamazepine-10,11-epoxide, p-nitrophenol, 3,5-dichlorophenol and caffeine were determined in the Elblag River and CTWA of metoprolol, diclofenac, 2-hydroxycarbamazepine, carbamazepine-10,11-epoxide, p-nitrophenol, 3,5-dichlorophenol and caffeine were determine in the Vistula Lagoon using MOFs-PSDs and a high-performance liquid chromatography coupled with triple quadrupole mass spectrometer.

2.
Chemosphere ; 332: 138855, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37149101

ABSTRACT

Progress in excogitation suitable strategies for monitoring chemical compounds in wastewater is an essential step for further research into the occurrence, impact, and fate of the pollutants in the aquatic environment. At present, it is desirable to advance and use economical, environmentally friendly and non-labour intensive methods of environmental analysis. In this study, carbon nanotubes (CNTs) were successfully applied, regenerated, and reused as a sorbent in passive samplers for monitoring contaminants in treated and untreated wastewater at three wastewater treatment plants (WWTPs) located in different urbanization areas in northern Poland. Three cycles of chemical and thermal regeneration of used sorbents were performed. It was shown that it is possible to regenerate CNTs a minimum of three times and reuse them in passive samplers while maintaining the desired sorption properties. The obtained results confirm that the CNTs are perfectly in line with the main principles of green chemistry and sustainability. Carbamazepine, ketoprofen, naproxen, diclofenac, p-nitrophenol, atenolol, acebutolol, metoprolol, sulfapyridine and sulfamethoxazole were detected in each of the WWTPs, both in treated and untreated wastewater. The obtained data drastically show the inefficiency of the removal of contaminants by conventional WWTPs. More importantly, the results even indicate negative contaminant removal in most cases, i.e. higher concentrations (up to 863%) of these substances in the effluent compared to the influent.


Subject(s)
Nanotubes, Carbon , Water Pollutants, Chemical , Wastewater , Environmental Monitoring , Water Pollutants, Chemical/analysis , Carbamazepine/analysis
3.
J Chromatogr A ; 1681: 463460, 2022 Oct 11.
Article in English | MEDLINE | ID: mdl-36070641

ABSTRACT

Inherent in the use of almost any analytical technique is the need to improve the separation efficiency and extract purity. One possibility for enhancing analytical methods is the application of substances / materials that functionalize components of the separation system. They interact with the material to be modified, either permanently or temporarily. Typically, organic solvents or salts are used for this purpose. The ionic liquids (ILs) are salts that remain in the liquid phase at temperatures below 100 ℃, what gives them advantage compared to traditional modifiers. This paper presents the range of applications of ILs in functionalized materials in analytical chemistry, as presented in publications from the last five years. Several types of techniques in which ILs are used are presented (HPLC, GC, electrophoresis, supported liquid membranes, passive sampling, various modification of solid-phase extraction), along with most interesting exemplary studies. As expected, imidazolium ILs are most commonly used. The application of ILs for functionalization in analytical techniques is extremely useful, but the problem is their cost and the low recovery rate. However, the rapid development in this field of science and the promising results encourage further work on the issue of ILs in functionalized materials.


Subject(s)
Ionic Liquids , Chemistry, Analytic , Chromatography, High Pressure Liquid/methods , Ionic Liquids/chemistry , Salts , Solvents/chemistry
4.
Sci Total Environ ; 836: 155551, 2022 Aug 25.
Article in English | MEDLINE | ID: mdl-35504373

ABSTRACT

Passive sampling is an interesting and cost-effective strategy for the quantification of micropollutants in the aquatic environment. When combined especially with a sensitive analytical method such as liquid chromatography coupled with triple quadrupole mass spectrometry (LC-MS/MS), the use of passive sampling devices (PSDs) enables long-term and reliable determination of a wide range of chemicals. In this study, carbon nanotubes (CNTs) were used as an innovative sorbent in POCIS-like samplers (Polar Organic Chemical Integrative Sampler). The developed CNTs-PSDs were calibrated by the flow-through method and the obtained sampling rates (Rs) of analytes were compared with the previously obtained Rs values using the semi-static method. Subsequently, passive samplers were placed in the Baltic Sea, the Nogat River, and the Sztumskie Pole Lake in order to sample and concentrate 28 chemical compounds belonging to the group of contaminants of emerging concern (CECs). For the first time, the effectiveness of the use of CNTs-PSDs in the field was proven by the quantification of carbamazepine, diclofenac, p-nitrophenol, bisphenol A, 3,5-dichlorophenol, 17-ß-estradiol, 17-α-ethinylestradiol and metoprolol in the tested surface waters. The obtained time-weighted average (TWA) concentrations of analytes ranged from 0.22 ± 0.12 ng/L (for metoprolol in the Nogat River) to 32.1 ± 2.4 ng/L (for bisphenol A in the Sztumskie Pole Lake). More importantly, CNTs-PSDs determined a greater amount of micropollutants than grab sampling and solid-phase extraction (SPE), which proves the advantage of passive sampling over grab sampling, especially when monitoring contaminants in the aquatic environment at low concentration levels.


Subject(s)
Nanotubes, Carbon , Water Pollutants, Chemical , Chromatography, Liquid/methods , Environmental Monitoring/methods , Metoprolol , Nanotubes, Carbon/analysis , Tandem Mass Spectrometry , Water Pollutants, Chemical/analysis
5.
J Inj Violence Res ; 14(1): 21-31, 2022 Jan.
Article in English | MEDLINE | ID: mdl-35014628

ABSTRACT

BACKGROUND: The purpose of this study was to analyze the co-occurrence of adult and child abuse based on the reports collected from the Polish police and social welfare institutions. METHODS: The study involved data concerning 468 households in Szczecin (Poland) inhabited by children where acts of violence between adults took place. The presented data refer to the years 2012-2103. The data came from so called Blue Card files, i.e. documents issued by the police and social workers in cases of domestic abuse, providing information about its forms, perpetrators, and victims. RESULTS: Domestic violence usually occurs between spouses and cohabitees (78%). The perpetrator was usually a man (88%). Violence usually lasted from 1 up to 3 years (30.0%). The most common forms of physical abuse against adults and children included pushing (79.5% of adults, 22.4% of children) and hitting (64.7% of adults, 16.6% of children), and psychologically abusive behaviors were mostly insults (91.9% of adults, 27.5% of children) and criticism (79.1% of adults, 21.5% of children). This work has shown that the longer the psychological abuse between adults lasts, the greater probability is that it will also be used against children. Child abuse is also associated with putting up resistance to the police by perpetrators. CONCLUSIONS: Summing up, in households where violence between adults is observed, actions should be taken to prevent violence against children.


Subject(s)
Child Abuse , Domestic Violence , Adult , Aggression/psychology , Child , Domestic Violence/psychology , Humans , Male , Police , Sexual Partners
6.
J Environ Sci (China) ; 101: 413-427, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33334535

ABSTRACT

Passive techniques are a constantly evolving approach to the long-term monitoring of micropollutants, including pharmaceuticals, in the aquatic environment. This paper presents, for the first time, the calibration results of a new CNTs-PSDs (carbon nanotubes used as a sorbent in passive sampling devices) with an examination of the effect of donor phase salinity, water pH and the concentration of dissolved humic acids (DHAs), using both ultrapure and environmental waters. Sampling rates (Rs) were determined for the developed kinetic samplers. It has been observed that the impact of the examined environmental factors on the Rs values strictly depends on the type of the analytes. In the case of ß-blockers, the only environmental parameter affecting their uptake rate was the salinity of water. A certain relationship was noted, namely the higher the salt concentration in water, the lower the Rs values of ß-blockers. In the case of sulfonamides, water salinity, water pH 7-9 and DHAs concentration decreased the uptake rate of these compounds by CNTs-PSDs. The determined Rs values differed in particular when the values obtained from the experiments carried out using ultrapure water and environmental waters were compared. The general conclusion is that the calibration of novel CNTs-PSDs should be carried out under physicochemical conditions of the aquatic phase that are similar to the environmental matrix.


Subject(s)
Nanotubes, Carbon , Water Pollutants, Chemical , Calibration , Environmental Monitoring , Sulfonamides , Water , Water Pollutants, Chemical/analysis
7.
Sci Total Environ ; 745: 140848, 2020 Nov 25.
Article in English | MEDLINE | ID: mdl-32758731

ABSTRACT

At the end of August 2019, in Warsaw, the sewage collection system of the Wastewater Treatment Plant malfunctioned. During the subsequent 12 days, over 3.6 million m3 of untreated sewage was introduced from the damaged collector directly into the Vistula River. It is one of the biggest known failures of its kind in the world so far. In this study we investigated to what extent the incident contributed to the increased discharge of anti-inflammatory drugs into the environment. The study covered the section from the point of discharge to the city of Torun (ca. 170 km downstream). It was found that in the river waters downstream of the damaged collector, the concentrations of selected pharmaceuticals increased considerably in comparison with the waters upstream of the collector. The highest concentrations were observed for paracetamol (102.9 µg/L), ibuprofen (5.3 µg/L) and diclofenac (4.8 µg/L). We also measured to what extent and at what rate these pollutants were distributed along the river. The effects of the incident were observed in further parts of the river after 16 days. In the study we also detected elevated concentrations of ibuprofen and diclofenac in the bottom sediments collected 6 weeks after the failure. Measurements of the levels of pharmaceuticals in estuarial and marine waters in the vicinity of the mouth of the Vistula River indicate that the incident did not significantly increase the load of these pollutants in the waters of the southern Baltic Sea.


Subject(s)
Pharmaceutical Preparations , Water Pollutants, Chemical/analysis , Anti-Inflammatory Agents , Cities , Environmental Monitoring , Sewage
8.
J Colloid Interface Sci ; 572: 396-407, 2020 Jul 15.
Article in English | MEDLINE | ID: mdl-32272314

ABSTRACT

Ionic liquids (ILs) containing distinct nitrogen-bearing organic cations (pyridinium, pyrrolidinium, imidazolium, ammonium, morpholinium) were first used for the preparation of 23 IL-TiO2 types of composites by ionic liquid assisted solvothermal synthesis. These 23 optimal ILs structures (i.e. compounds exhibiting an optimal combination of specific properties, functionality, and safety) for synthesis and experimental validation were selected by computational high-throughput screening from a combinatorically created library containing 836 ILs theoretically designed and characterized candidates. Then, selected IL-TiO2 structures with potential photocatalytic activity were synthesized with the use of solvothermal reaction. Then, the decomposition level, the role of the individual IL cation structure on the morphology, thermal stability, surface and photocatalytic properties of the IL-TiO2 microparticles were determined experimentally. The chemoinformatic analysis of the relationship between the structure of the ionic liquid, its thermal stability under the conditions of synthesis and photocatalytic activity was applied for the first time. The results presented here are the first step in the development of methodology (combined experimental and theoretical) that may simplify the procedure of designing safer and more efficient TiO2-based photocatalyst. The developed computational methodology makes it possible to predict properties of newly synthesized IL-TiO2 materials before synthesis and identifies structural features of ILs that influence the efficiency of IL-TiO2 system. The presented approach reduces the number and cost of necessary experiments, as well as increases the success ratio of efficient TiO2-based photocatalyst design by a selection of optimal IL structures (i.e. ionic liquid characterized by a combination of most promising physicochemical features).

9.
Crit Rev Anal Chem ; 50(1): 1-28, 2020.
Article in English | MEDLINE | ID: mdl-31204504

ABSTRACT

Aquatic passive samplers have been extensively tested and deployed in the field over the past two decades. Among these devices is relatively recently developed the Polar Organic Chemical Integrative Sampler (POCIS) for isolation of hydrophilic organic micropollutants in aquatic environment. The use of POCIS allows the measurement of low and fluctuating trace concentrations of such micropollutants, which is often troublesome using classical sampling. In this review, POCIS applications based on numerous articles to assess the suitability of these devices for use in environmental analytics information were summarized. Additionally, the possibilities of using POCIS for the isolation of complex chemical mixtures in order to highlight the high potential of this devices were presented. The types of sorbents used in POCIS, exposure duration and sampling media are juxtapose in this review. Based on the existing literature, attention was paid to both promising opportunities but also to limitations of passive methods.


Subject(s)
Biosensing Techniques/instrumentation , Environmental Monitoring/instrumentation , Organic Chemicals/analysis , Water Pollutants, Chemical/analysis , Biosensing Techniques/methods , Environmental Monitoring/methods , Fluorocarbons/analysis
10.
Nanomaterials (Basel) ; 9(5)2019 May 15.
Article in English | MEDLINE | ID: mdl-31096544

ABSTRACT

Ionic liquids (ILs) could serve as a structuring agent, a solvent, or a source of dopant during solvothermal synthesis of semiconductors particles. To understand the role of IL during formation of TiO2 particles, it is necessary to study the stability of this IL in solvothermal synthesis conditions, as well as studying the surface properties of formed TiO2 particles. In view of this, the effect of the 2,3,5-triphenyltetrazolium chloride IL ([TPTZ][Cl]) thermal decomposition during the solvothermal reaction and IL content in the reaction system on photoactivity of TiO2 microparticles has been systematically investigated. The samples obtained by using [TPTZ][Cl] exhibited remarkable photocatalytic properties in phenol degradation reaction under visible light. HPLC analysis of the solvothermal reaction medium and X-ray photoelectron spectroscopy (XPS) analysis of TiO2 particles revealed that [TPTZ][Cl] was decomposed completely and was incorporated into the TiO2 lattice. Generally, increasing the reaction time (1, 4, 12, and 24 h) promoted the TiO2 microspheres formation, as well as raising the visible light-induced photocatalytic activity of the photocatalysts. Longer reaction time was also accompanied by an increase in the efficiency of 2,3,5-triphenyltetrazolium chloride decomposition. The properties of the photocatalysts were investigated by means of UV-VIS diffuse reflectance spectroscopy (DRS), BET surface area measurements, scanning electron microscopy (SEM), X-ray powder diffraction (XRD) analysis, and XPS.

12.
Psychiatr Pol ; 52(5): 873-886, 2018 Oct 27.
Article in English, Polish | MEDLINE | ID: mdl-30584820

ABSTRACT

OBJECTIVES: The military service of Polish soldiers on missions abroad began in 1953. Many years of experience of the Polish army as well as the armed forces of other countries show that being in a mission area has a significant impact on soldiers' mental health. Soldiers experience problems with anxiety disorders, depression and posttraumatic stress, which is associated with a difficult return to family life. The aim of the paper was to analyze psychosocial aspects of participation of the Polish Armed Forces in combat missions outside the country. METHODS: The study involved a group of 102 soldiers serving in the Military Unit No. 4092 in Walcz, Military Unit No. 4094 in Walcz, and the Military Academy of Land Forces in Wroclaw. All subjects are veterans of missions outside Poland. The research method was the diagnostic survey method. Three standardized research tools were used: the State-Trait Anxiety Inventory (STAI), NEO-FFI Personality Inventory, Beck's Depression Scale, and the author's questionnaire. RESULTS: The studies have shown relationships between the level of anxiety in soldiers - veterans of missions abroad and strong battlefield stressors to which they had been subjected, and their family situation and non-institutional methods of psychological support they had received during their stay in the mission area. During the studies a factor was distinguished that contributes to the feeling of incomprehension of soldiers by their relatives after returning home. CONCLUSIONS: 1. A higher level of anxiety is observed in soldiers who had experienced lifethreatening situations during their missions. 2. Having children is a factor that increases the level of anxiety in veterans on missions abroad. 3. Regular contact with families left behind in the country is associated with a lower sense of fear in soldiers.


Subject(s)
Combat Disorders/psychology , Mental Health/statistics & numerical data , Military Personnel/psychology , Veterans/psychology , Warfare/psychology , Adaptation, Psychological , Adult , Humans , Male , Poland , Stress Disorders, Post-Traumatic/psychology
13.
Water Air Soil Pollut ; 229(8): 253, 2018.
Article in English | MEDLINE | ID: mdl-30237636

ABSTRACT

The differences in effectiveness of multi-walled carbon nanotubes (MWCNTs) as the dispersive solid-phase extraction (dSPE) sorbent for the selective extraction of polycyclic aromatic hydrocarbons (PAHs) were explained on the basis of theoretical study. It was observed that for low molecular weight PAHs, the recoveries using non-helical and helical MWCNTs were similar. In contrary, for PAHs containing five or more aromatic rings, the extraction efficiency was higher using HMWCNTs than for non-helical ones. Principle component analysis (PCA) as well as providing structural parameters and interaction energies for adsorption processes (PAH + CNT → PAH-CNT) have been used for this purpose. All the PAH + CNT → PAH-CNT adsorption processes considered were found to be thermodynamically favorable. However, the adsorption energies (Eads) for PAHs and the helical carbon nanotube surface estimated for the B(a)P-HCNT and I(1,2,3-cd)P-HCNT are substantially less negative than those observed for PAH molecules interacting with the non-helical CNT. Namely, the Eads calculated in simulated aqueous environment for the B(a)P-MWCNT(6,2) and I(1,2,3-cd)P-MWCNT(6,2) were respectively - 43.32 and - 59.98 kcal/mol, while values of only - 7.75 kcal/mol (B(a)P-HCNT) and - 9.13 kcal/mol (I(1,2,3-cd)P-HCNT) were found for the corresponding PAH-HCNT systems. Therefore, we conclude that the replacement of MWCNTs with HCNTs leads to PAH-HCNT systems in which the interaction energies are much smaller than those estimated for the corresponding PAH-MWCNT systems. HMWCNTs are therefore recommended as the dSPE sorbent phase for the extraction of both low and high molecular weight PAHs from water samples.

14.
Psychiatr Pol ; 52(1): 103-113, 2018 Feb 28.
Article in English, Polish | MEDLINE | ID: mdl-29704418

ABSTRACT

OBJECTIVES: Domestic violence is a phenomenon stemming from various social issues. One of such issues, which arouses much interest, is the behavior of psychiatric patients using violence in their family. The aim of the following work was the analysis of the phenomenon of violence with reference to perpetrators-psychiatric patients from the Szczecin area in the years 2012-2013. In addition, the authors'aim was also to indicate that the beliefs held by society on aggression of psychiatric patients are not confirmed by the actual state. METHODS: The research was conducted with the research tool prepared on the basis of the "Blue Cards" - part A questionnaire. For data gathering, the document analysis method -survey-was used. 141 psychiatric patients constituted the research group. These people have already used violence against adults, and they already had the Blue Card. The members of the group were examined on the basis of several variables, such as sex, age, and the form of the violence used. RESULTS: Men were the ones most frequently using violence, and with regard to the forms of violence, it was most often hitting and pushing. As far as psychic violence is concerned, most perpetrators admitted they used to humiliate, criticize and bother their victims. Regarding other types of behaviors among the psychiatric patients using violence, as many as 96 respondents admitted that they used punishable threats and insults, and 71 respondents admitted they destroyed and damaged property. CONCLUSIONS: On the basis of the conducted analysis, the authors claim that the obtained data do not confirm the common belief that psychiatric patients indicate an increased level of aggression.


Subject(s)
Aggression/psychology , Crime Victims/statistics & numerical data , Criminal Behavior , Mentally Ill Persons/psychology , Violence/statistics & numerical data , Adult , Female , Humans , Male , Mental Disorders/epidemiology , Middle Aged , Poland , Risk Assessment , Young Adult
15.
Chemosphere ; 201: 32-40, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29518732

ABSTRACT

The presence of anticancer drugs in the environment raises a major concern due to their potentially negative impact on living organisms, as they cause, inter alia, teratogenic, mutagenic, carcinogenic effects on growing cells. The main source of these pharmaceuticals in the environment is the ineffectively treated wastewaters, hence the efficient methods for their removal are required. In this study, we have evaluated for the first time the applicability of different Multi-Walled Carbon Nanotubes (MWCNTs) as alternative adsorbents for the removal of three popular anticancer drugs from water matrices, which are detected in waste/hospital waters at the concentrations even up to µg L-1: cyclophosphamide (CP), ifosfamide (IF) and 5-fluorouracil (5-FU). It was observed that adsorption equilibrium time was reached after 20 min for each compound and CNTs. Moreover, CP has the highest sorption potential (Kd up to 1597 L kg-1) for all CNTs and CNTs with the highest surface area have the greatest adsorption capacity. Isotherms were fitted best to the Freundlich model. Significant influence of pH in the range 4-9 and ionic strength was not observed what may indicate that adsorption is not dependent on fluctuation of basic environmental conditions.


Subject(s)
Antineoplastic Agents/analysis , Models, Theoretical , Nanotubes, Carbon/chemistry , Wastewater/chemistry , Water Pollutants, Chemical/analysis , Water Purification/methods , Adsorption , Antineoplastic Agents/chemistry , Hydrogen-Ion Concentration , Osmolar Concentration , Surface Properties , Water Pollutants, Chemical/chemistry
16.
Chemosphere ; 190: 280-286, 2018 Jan.
Article in English | MEDLINE | ID: mdl-28992481

ABSTRACT

The knowledge of the sorption mechanism of different chemicals onto third generation carbon sorbents such as carbon nanotubes (CNTs) is needed in order to project systems for the effective removal of pollutants from the environment. This paper reports evaluation of the sorption mechanism of selected ionic liquids (ILs), being considered as potential pollutant in environment, onto various CNTs. CNTs characterized by the smallest diameter and the biggest surface area showed the highest sorption capacity to isolate ILs from an aqueous solution. CNTs with a bigger diameter, a functionalized surface and particularly a helical shape showed a lower sorption capacity. The sorption mechanism has been defined as complex, including van der Waals, π-π and electrostatic interactions with dominating π-π interactions. Due to the relatively high sorption coefficient (355.98 ± 20.69-6397.10 ± 355.42 L kg-1 depending on the IL) the study showed that multi-walled carbon nanotubes can potentially be used to effectively isolate ILs from an aqueous solution. Moreover, proved in this study, the fast sorption kinetic, and uncomplicated regeneration process, leading to an even higher sorption capacity, means that CNTs are promising material which could find potential applications in the treatment of water contaminated by ILs.


Subject(s)
Environmental Pollutants/isolation & purification , Environmental Restoration and Remediation/methods , Ionic Liquids/chemistry , Nanotubes, Carbon/chemistry , Adsorption , Environmental Pollutants/chemistry , Ionic Liquids/isolation & purification , Kinetics , Static Electricity , Water/chemistry , Water Purification/methods
17.
Talanta ; 165: 405-411, 2017 Apr 01.
Article in English | MEDLINE | ID: mdl-28153275

ABSTRACT

In this publication, a new dispersive solid-phase extraction (dSPE) method combined with gas chromatography-mass spectrometry and atomic absorption spectrometry was developed for the simultaneous determination of 9 PAHs and chromium, cadmium, and lead ions in water samples. For this purpose, non-modified multi-walled carbon nanotubes (MWCNTs) and modified -MWCNTs (OH-MWCNTs and COOH-MWCNTs) were used as sorbents. Parameters affecting the extraction, such as the amount of sorbent, the pH of the sample, the composition and volume of eluents and the extraction time were optimized. Sequential elution was applied using 6mL of dichloromethane for the elution of PAHs and 5mL of 3M HNO3 for cadmium, lead, and chromium. The optimal values of other parameters were as follows: 50mg of sorbent per 250mL of water sample, pH in a range from 6 to 7 and 30min of contact time between the sorbent and analytes. The results demonstrated the high extraction capability of modified MWCNTs with recoveries between 80 and 101% for cadmium, chromium, and lead ions and between 83 and 92% for PAHs. Finally, the optimized method was validated, and the matrix effects were determined.

18.
Talanta ; 164: 700-707, 2017 Mar 01.
Article in English | MEDLINE | ID: mdl-28107994

ABSTRACT

Nowadays, carbon nanotubes, as commercially available materials, have attracted great attention because of their unique physicochemical properties, especially their strong adsorption abilities. This paper deals with the possibilities and limitations of the application of multi-walled carbon nanotubes as an alternative sorbent in passive sampling devices for the isolation of selected pharmaceuticals and phenolic compounds directly in water samples. Compounds with different properties, including sulfapyridine, sulfamethoxazole, carbamazepine, p-nitrophenol, 17-ß-estradiol, 3,5-dichlorophenol and diclofenac were selected as model compounds. Firstly, the influence of several parameters on the extraction efficiency was defined, then the matrix effect and standard validation parameters were established. Under optimized conditions, the proposed analytical methods exhibited good validation parameters, including excellent linearity with R2 >0.999, the LODs were found to be between 0.01-0.5µgL-1 and the LOQ ranged from 0.05 to 1.5µgL-1. Recovery values obtained for model compounds were 79,8±0.2% for sulfapyridine, 41,5±0.1% for sulfamethoxazole, 96,6±1,5% for carbamazepine, 70,5±0.1% for p-nitrophenol, 77,1±0.5% for 17-ß-estradiol, 103,1±1.8% for 3,5-dichlorophenol and 76,3±1.4% for diclofenac. This study provides useful data regarding the sorption process on MWCNTs and definitely evaluates the application potential of these types of sorbents in passive sampling devices.


Subject(s)
Chemical Fractionation/methods , Nanotubes, Carbon/chemistry , Pharmaceutical Preparations/isolation & purification , Phenols/isolation & purification , Water/chemistry , Hydrogen-Ion Concentration , Limit of Detection , Pharmaceutical Preparations/analysis , Pharmaceutical Preparations/chemistry , Phenols/analysis , Phenols/chemistry , Solvents/chemistry
19.
Crit Rev Anal Chem ; 47(1): 76-91, 2017 Jan 02.
Article in English | MEDLINE | ID: mdl-27404790

ABSTRACT

Carbon nanotubes (CNTs) are currently one of the most promising groups of materials with some interesting properties, such as lightness, rigidity, high surface area, high mechanical strength in tension, good thermal conductivity or resistance to mechanical damage. These unique properties make CNTs a competitive alternative to conventional sorbents used in analytical chemistry, especially in extraction techniques. The amount of work that discusses the usefulness of CNTs as a sorbent in a variety of extraction techniques has increased significantly in recent years. In this review article, the most important feature and different applications of solid-phase extraction (SPE), including, classical SPE and dispersive SPE using CNTs for pesticides isolation from different matrices, are summarized. Because of high number of articles concerning the applicability of carbon materials to extraction of pesticides, the main aim of proposed publication is to provide updated review of the latest uses of CNTs by covering the period 2006-2015. Moreover, in this review, the recent papers and this one, which are covered in previous reviews, will be addressed and particular attention has been paid on the division of publications in terms of classes of pesticides, in order to systematize the available literature reports.


Subject(s)
Nanotubes, Carbon/chemistry , Pesticides/isolation & purification , Solid Phase Extraction , Molecular Structure , Pesticides/chemistry
20.
Article in English | MEDLINE | ID: mdl-27659871

ABSTRACT

Continous renal replacement therapy (CRRT) is particularly recommended for septic shock patients in intensive care units. The CRRT technique used most frequently is high volume continuous veno-venous haemofiltration. It provides a high rate of clearance of uremic toxins and inflammatory cytokines. However, it should also be taken into account that substances important for homeostasis may be concurrently unintentionally removed. Accordingly, water-soluble vitamins can be removed during continuous renal replacement therapy, and the estimate of the loss is critical to ensure appropriate supplementation. The aim of this work was to develop a simple methodology for a purification step prior to the LC-MS/MS determination of water-soluble vitamins in ultrafiltrate samples. For this purpose, two types of resin and a mix of resins were used as sorbents for the purification step. Moreover, parameters such as the amount of resin and the extraction time were optimized. The LC-MS/MS method was developed and validated for final determination of 11 vitamins. The results demonstrated the high purification capability of DEAE Sephadex resin with recoveries between 65 and 101% for water-soluble vitamins from ultrafiltrate samples. An optimized method was applied to assess the loss of B-group vitamins in patients after 24h of renal replacement therapy. The loss of vitamins B2, B6 pyridoxamine, B6 pyridoxal, B7, B1, and B5 in ultrafiltrates was similar in all patients. In the native ultrafiltrates, vitamins B6 pyridoxine, B9 and B12 were not detected.


Subject(s)
Chromatography, Ion Exchange/methods , Renal Replacement Therapy , Tandem Mass Spectrometry/methods , Vitamin B Complex/analysis , Linear Models , Renal Dialysis
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