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Selected papers from the latest issue:
Multiresidue analysis of aromatic organochlorines in soil by gas chromatography-mass spectrometry and QuEChERS extraction based on water/dichloromethane partitioning. Comparison with Accelerated Solvent Extraction
03 March 2012, 22:45:49
Publication year: 2012
Source: Talanta, Available online 3 March 2012
Florent Rouvière, Audrey Buleté, Cécile Cren-Olivé, Carine Arnaudguilhem
A novel multiresidue method was developed for the simultaneous analysis of 34 organochlorines, including chlorobenzenes, chlorophenols, chlorinated hydrocarbons and chlorinated olefins, in soil by GC-MS, using a QuEChERS-based extraction. The conventional QuEChERS method was optimised and, for the first time, the use of a non miscible-water solvent was required. The method was compared to ASE extraction, versatile technique widely used for the soils’ extraction and QuEChERS-based method was shown to be the most efficient in terms of recoveries, simplicity and rapidity. For ASE, recoveries between 42 and 85% were obtained for the majority of the compounds. However, due to the high pressure, all volatile compounds were lost. In opposite, QuEChERS extraction allowed detection and quantification of all the compounds with recoveries between 60 and 100%. Moreover, no additional clean up by dispersive SPE on PSA was necessary, which allowed reducing the cost of the analysis.Performance of the method was assessed. The method was linear over the range of concentration of 10-5000 μg Kg. Precision, expressed as intra-day precision and inter-day variation was verified at three concentrations. Limits of detection were from 2 to 50 μg Kgand limits of quantification from 7 to 170 μg Kgfor the majority of the compounds (chlorobenzenes and chlorinated hydrocarbons and olefins), except for chlorophenols. The method was further applied to different soils coming from a contaminated industrial site, where a new environmental remediation process, using phytoremediation, was tested. The results showed that the method could be applied to any kind of soils (mineral or organic) and was appropriate to very volatile compounds which were not available with conventional technique.
Source: Talanta, Available online 3 March 2012
Florent Rouvière, Audrey Buleté, Cécile Cren-Olivé, Carine Arnaudguilhem
A novel multiresidue method was developed for the simultaneous analysis of 34 organochlorines, including chlorobenzenes, chlorophenols, chlorinated hydrocarbons and chlorinated olefins, in soil by GC-MS, using a QuEChERS-based extraction. The conventional QuEChERS method was optimised and, for the first time, the use of a non miscible-water solvent was required. The method was compared to ASE extraction, versatile technique widely used for the soils’ extraction and QuEChERS-based method was shown to be the most efficient in terms of recoveries, simplicity and rapidity. For ASE, recoveries between 42 and 85% were obtained for the majority of the compounds. However, due to the high pressure, all volatile compounds were lost. In opposite, QuEChERS extraction allowed detection and quantification of all the compounds with recoveries between 60 and 100%. Moreover, no additional clean up by dispersive SPE on PSA was necessary, which allowed reducing the cost of the analysis.Performance of the method was assessed. The method was linear over the range of concentration of 10-5000 μg Kg. Precision, expressed as intra-day precision and inter-day variation was verified at three concentrations. Limits of detection were from 2 to 50 μg Kgand limits of quantification from 7 to 170 μg Kgfor the majority of the compounds (chlorobenzenes and chlorinated hydrocarbons and olefins), except for chlorophenols. The method was further applied to different soils coming from a contaminated industrial site, where a new environmental remediation process, using phytoremediation, was tested. The results showed that the method could be applied to any kind of soils (mineral or organic) and was appropriate to very volatile compounds which were not available with conventional technique.
Highlights
► Optimisation of QuEChERS method for the analysis of organochlorines and phenols ► Compared to ASE, the developed QuEChERS method is rapid and easy to use ► Better recoveries with QuEChERS-based method than ASE ► Contrary to conventional methods, no water elimination. Then, no loss of volatiles ► QuEChERS-based method provides clean extracts with few matrix effectsEnhanced fluorescence sensing of melamine based on thioglycolic acid-capped CdS quantum dots
03 March 2012, 22:45:49
Publication year: 2012
Source: Talanta, Available online 2 March 2012
Guang-Li Wang, Huan-Jun Jiao, Xiao-Ying Zhu, Yu-Ming Dong, Zai-Jun Li
A sensitive and simple method for the determination of melamine (MA) was developed based on the fluorescence enhancement effect of MA for thioglycolic acid-capped (TGA-capped) CdS quantum dots (QDs). Under optimum conditions, a good linear relationship was obtained from 2.0 × 10to 5.0 × 10 M. The detection limit was 1.0 × 10 M, which was much lower than the safety limit (2.5 ppm in USA and the UK; 1 ppm for infant formula in China). The solution pH, the adding sequence of the buffer solution and MA and surface modifiers of CdS QDs greatly influenced the enhancement extent of MA for CdS QDs. The fluorescence enhancement was attributed to the surface passivation of the surface states of QDs by amine group of MA. The method was applied to detect MA in raw milk with satisfactory results. The proposed method manifested several advantages such as high sensitivity, short analysis time, low cost and ease of operation.
Source: Talanta, Available online 2 March 2012
Guang-Li Wang, Huan-Jun Jiao, Xiao-Ying Zhu, Yu-Ming Dong, Zai-Jun Li
A sensitive and simple method for the determination of melamine (MA) was developed based on the fluorescence enhancement effect of MA for thioglycolic acid-capped (TGA-capped) CdS quantum dots (QDs). Under optimum conditions, a good linear relationship was obtained from 2.0 × 10to 5.0 × 10 M. The detection limit was 1.0 × 10 M, which was much lower than the safety limit (2.5 ppm in USA and the UK; 1 ppm for infant formula in China). The solution pH, the adding sequence of the buffer solution and MA and surface modifiers of CdS QDs greatly influenced the enhancement extent of MA for CdS QDs. The fluorescence enhancement was attributed to the surface passivation of the surface states of QDs by amine group of MA. The method was applied to detect MA in raw milk with satisfactory results. The proposed method manifested several advantages such as high sensitivity, short analysis time, low cost and ease of operation.
Highlights
► A highly sensitive “turn-on” sensor for melamine (MA) ► MA induced obvious fluorescence enhancement in acidic solutions ► Amine group of MA could passivate the surface effect ► The surface modifiers of CdS influenced the enhancement extent ► MA improved the sensitivity for copper (II) ion detectionA Pt layer/Pt disk electrode configuration to evaluate respiration and alkaline phosphatase activities of mouse embryoid bodies
03 March 2012, 22:45:49
Publication year: 2012
Source: Talanta, Available online 2 March 2012
Raquel Obregon, Yoshiko Horiguchi, Toshiharu Arai, Shihomi Abe, Yuanshu Zhou, ...
A Pt layer/Pt disk electrode configuration was used as a scanning electrochemical microscopy (SECM) probe. The glass seal part of the insulator was covered with a Pt layer to form an exposed pseudo reference electrode. In a HEPES-based medium at pH 7.5, the half-wave potential (E1/2) for [Fe(CN)6]oxidation and O2reduction measured versus the internal Pt pseudo reference was shifted by about–0.2 V, compared with the E1/2measured versus the external Ag/AgCl reference electrode. The shape and the current of the cyclic voltammograms (CVs) did not change notably over time, indicating that the Pt layer is sufficiently stable to be used as an integrated pseudo reference for voltammetric measurements. To demonstrate the suitability for SECM applications, the Pt/Pt probe configuration was used for measuring the oxygen consumption and the alkaline phosphatase (ALP) activity of a single mouse embryoid body (mEB). Ten individual mEB samples were characterized to monitor the oxygen concentration profile. Oxygen reduction currents were monitored at–0.7 V versus the Pt pseudo reference and compared with those monitored at–0.5 V versus Ag/AgCl. The respiration rate of mEBs becomes greater with increasing cultivation dates. We have plotted the oxygen consumption rate (F(O2)) of each mEB sample, measured versus the Pt layer and versus Ag/AgCl. The linearity of the plot was excellent (coefficient of determination R = 0.90). The slope of the least squares method was 1. In a 1.0 mMp-aminophenylphospate (PAPP) HEPES buffer (pH 9.5) solution, APL activity of mEBs can be characterized, to monitor thep-aminophenol (PAP) oxidation current. ALP catalyzes the hydrolysis of PAPP to PAP. The E1/2for PAP oxidation measured versus the Pt layer was not shifted, compared with the E1/2versus Ag/AgCl. The mEB samples were characterized to monitor the PAP concentration profile. PAP oxidation currents were monitored at +0.3 V versus the Pt layer and compared with those monitored at +0.3 V versus Ag/AgCl. We have plotted the PAP production rate (F(PAP)) of each mEB sample, measured versus the Pt layer and versus Ag/AgCl. In this case, the linearity of the plot became slightly scattered, but it was found to be possible to evaluate ALP activities of mEB samples utilizing the Pt/Pt probe configuration. This type of probe is very useful because it is not necessary to insert a reference electrode into the measuring solution to obtain an electrical connection, and thus electrochemical measurement in a small volume becomes much easier.
Source: Talanta, Available online 2 March 2012
Raquel Obregon, Yoshiko Horiguchi, Toshiharu Arai, Shihomi Abe, Yuanshu Zhou, ...
A Pt layer/Pt disk electrode configuration was used as a scanning electrochemical microscopy (SECM) probe. The glass seal part of the insulator was covered with a Pt layer to form an exposed pseudo reference electrode. In a HEPES-based medium at pH 7.5, the half-wave potential (E1/2) for [Fe(CN)6]oxidation and O2reduction measured versus the internal Pt pseudo reference was shifted by about–0.2 V, compared with the E1/2measured versus the external Ag/AgCl reference electrode. The shape and the current of the cyclic voltammograms (CVs) did not change notably over time, indicating that the Pt layer is sufficiently stable to be used as an integrated pseudo reference for voltammetric measurements. To demonstrate the suitability for SECM applications, the Pt/Pt probe configuration was used for measuring the oxygen consumption and the alkaline phosphatase (ALP) activity of a single mouse embryoid body (mEB). Ten individual mEB samples were characterized to monitor the oxygen concentration profile. Oxygen reduction currents were monitored at–0.7 V versus the Pt pseudo reference and compared with those monitored at–0.5 V versus Ag/AgCl. The respiration rate of mEBs becomes greater with increasing cultivation dates. We have plotted the oxygen consumption rate (F(O2)) of each mEB sample, measured versus the Pt layer and versus Ag/AgCl. The linearity of the plot was excellent (coefficient of determination R = 0.90). The slope of the least squares method was 1. In a 1.0 mMp-aminophenylphospate (PAPP) HEPES buffer (pH 9.5) solution, APL activity of mEBs can be characterized, to monitor thep-aminophenol (PAP) oxidation current. ALP catalyzes the hydrolysis of PAPP to PAP. The E1/2for PAP oxidation measured versus the Pt layer was not shifted, compared with the E1/2versus Ag/AgCl. The mEB samples were characterized to monitor the PAP concentration profile. PAP oxidation currents were monitored at +0.3 V versus the Pt layer and compared with those monitored at +0.3 V versus Ag/AgCl. We have plotted the PAP production rate (F(PAP)) of each mEB sample, measured versus the Pt layer and versus Ag/AgCl. In this case, the linearity of the plot became slightly scattered, but it was found to be possible to evaluate ALP activities of mEB samples utilizing the Pt/Pt probe configuration. This type of probe is very useful because it is not necessary to insert a reference electrode into the measuring solution to obtain an electrical connection, and thus electrochemical measurement in a small volume becomes much easier.
Graphical abstract
Highlights
► An integrated probe was fabricated, with working/pseudo reference electrode ► We measured oxygen consumption and alkaline phosphatase activity of a single muse embryoid bodiy ► The consumption pattern observed agreed well with the conventional SECM methodPolymer modified glassy carbon electrode for the electrochemical determination of caffeine in coffee
03 March 2012, 22:45:49
Publication year: 2012
Source: Talanta, Available online 2 March 2012
Meareg Amare, Shimelis Admassie
4-amino-3-hydroxynaphthalene sulfonic acid (AHNSA) was electropolymerized on a glassy carbon electrode. The deposited film showed electrocatalytic activity towards the oxidation of caffeine. The polymer-modified electrode showed high sensitivity, selectivity and stability in the determination of caffeine in coffee. The peak current increased linearly with the concentration of caffeine in the range of 6 × 10–4 × 10 mol L, with a detection limit of 1.37 × 10 mol L(LoD = 3δ/slope). Analysis of caffeine in coffee was affected neither by sample matrices nor by structurally similar compounds. Recoveries ranging between 93.75 ± 2.32 and 100.75 ± 3.32 were achieved from coffee extracts indicating the applicability of the developed method for real sample analyses.
Source: Talanta, Available online 2 March 2012
Meareg Amare, Shimelis Admassie
4-amino-3-hydroxynaphthalene sulfonic acid (AHNSA) was electropolymerized on a glassy carbon electrode. The deposited film showed electrocatalytic activity towards the oxidation of caffeine. The polymer-modified electrode showed high sensitivity, selectivity and stability in the determination of caffeine in coffee. The peak current increased linearly with the concentration of caffeine in the range of 6 × 10–4 × 10 mol L, with a detection limit of 1.37 × 10 mol L(LoD = 3δ/slope). Analysis of caffeine in coffee was affected neither by sample matrices nor by structurally similar compounds. Recoveries ranging between 93.75 ± 2.32 and 100.75 ± 3.32 were achieved from coffee extracts indicating the applicability of the developed method for real sample analyses.
Determination of mercury in fish otoliths by cold vapor generation inductively coupled plasma mass spectrometry (CVG-ICP-MS)
03 March 2012, 22:45:49
Publication year: 2012
Source: Talanta, Available online 2 March 2012
Erdal Kenduzler, Mehmet Ates, Zikri Arslan, Melanie McHenry, Paul B. Tchounwou
A method based on cold vapor generation inductively coupled plasma mass spectrometry (CVG-ICP-MS) has been developed for determination of inorganic mercury, Hg(II), and total mercury in fish otoliths. Sodium borohydride (NaBH4) was used as the only reducing agent and its concentration was optimized across an acidity gradient to selectively reduce Hg(II) without affecting methylmercury, CH3Hg(I). Inorganic Hg was quantitatively reduced to elemental mercury (Hg) with 1 × 10% (m/v) NaBH4. CH3Hg(I) required a minimum of 0.5% (m/v) NaBH4for complete reduction. Increasing the HCl concentration of solution to 5% (v/v) improved the selectivity toward Hg(II) as it decreased the signals from CH3Hg(I) to baseline levels. Potassium ferricyanide solution was the most effective in eliminating the memory effects of Hg compared with a number of chelating and oxidizing agents, including EDTA, gold chloride, thiourea, cerium ammonium nitrate and 2-mercaptoethylamine chloride. The relative standard deviation (RSD) was less than 5% for 1.0 μg LHg(II) solution. The detection limits were 4.2 and 6.4 ng L(ppt) for Hg(II) and total Hg, respectively. Sample dissolution conditions and recoveries were examined with ultra-pure CaCO3(99.99%) spiked with Hg(II) and CH3HgCl. Methylmercury was stable when dissolution was performed with up to 20% (v/v) HCl at 100 °C. Recoveries from spiked solutions were higher than 95% for both Hg(II) and CH3Hg(I). The method was applied to the determination of Hg(II) and total Hg concentrations in the otoliths of red emperor (CRM 22) and Pacific halibut. Total Hg concentration in the otoliths was 0.038 ± 0.004 μg gfor the red emperor and 0.021 ± 0.003 μg gfor the Pacific halibut. Inorganic Hg accounted for about 25% of total Hg indicating that Hg in the otoliths was predominantly organic mercury (e.g., methylmercury). However, as opposed to the bioaccumulation in tissues, methylmercury levels in otoliths was very low suggesting a different route of uptake, most likely through the deposition of methylmercury available in the water.
Source: Talanta, Available online 2 March 2012
Erdal Kenduzler, Mehmet Ates, Zikri Arslan, Melanie McHenry, Paul B. Tchounwou
A method based on cold vapor generation inductively coupled plasma mass spectrometry (CVG-ICP-MS) has been developed for determination of inorganic mercury, Hg(II), and total mercury in fish otoliths. Sodium borohydride (NaBH4) was used as the only reducing agent and its concentration was optimized across an acidity gradient to selectively reduce Hg(II) without affecting methylmercury, CH3Hg(I). Inorganic Hg was quantitatively reduced to elemental mercury (Hg) with 1 × 10% (m/v) NaBH4. CH3Hg(I) required a minimum of 0.5% (m/v) NaBH4for complete reduction. Increasing the HCl concentration of solution to 5% (v/v) improved the selectivity toward Hg(II) as it decreased the signals from CH3Hg(I) to baseline levels. Potassium ferricyanide solution was the most effective in eliminating the memory effects of Hg compared with a number of chelating and oxidizing agents, including EDTA, gold chloride, thiourea, cerium ammonium nitrate and 2-mercaptoethylamine chloride. The relative standard deviation (RSD) was less than 5% for 1.0 μg LHg(II) solution. The detection limits were 4.2 and 6.4 ng L(ppt) for Hg(II) and total Hg, respectively. Sample dissolution conditions and recoveries were examined with ultra-pure CaCO3(99.99%) spiked with Hg(II) and CH3HgCl. Methylmercury was stable when dissolution was performed with up to 20% (v/v) HCl at 100 °C. Recoveries from spiked solutions were higher than 95% for both Hg(II) and CH3Hg(I). The method was applied to the determination of Hg(II) and total Hg concentrations in the otoliths of red emperor (CRM 22) and Pacific halibut. Total Hg concentration in the otoliths was 0.038 ± 0.004 μg gfor the red emperor and 0.021 ± 0.003 μg gfor the Pacific halibut. Inorganic Hg accounted for about 25% of total Hg indicating that Hg in the otoliths was predominantly organic mercury (e.g., methylmercury). However, as opposed to the bioaccumulation in tissues, methylmercury levels in otoliths was very low suggesting a different route of uptake, most likely through the deposition of methylmercury available in the water.
Highlights
► Mercury in fish otoliths is determined by cold vapor generation ICP-MS. ► Inorganic and methylmercury are determined selectively using NaBH4as only reductant. ► Potassium ferricyanide ensures effective cleaning of residual Hg from sampling system. ► Mercury in fish otoliths is mostly organic mercury. ► Mercury concentrations in fish otoliths show variations with geochemistry of habitats.Gold-Silver- Nanoclusters Having CHOLİC ACİD Imprinted Nanoshell
03 March 2012, 22:45:49
Publication year: 2012
Source: Talanta, Available online 2 March 2012
Aytaç Gültekin, Arzu Ersöz, Adil Denizli, Rıdvan Say
Molecular imprinted polymers (MIPs) as a recognition element for sensors are increasingly of interest and MIP-nanoparticles have started to appear in the literature. In this study, we have proposed a novel thiol ligand-capping method with polymerizable methacryloylamido-cysteine (MAC) attached to gold-silver-nanoclusters reminiscent of a self-assembled monolayer and have reconstructed surface shell by synthetic host polymers based on molecular imprinting method for cholic acid recognition. In this method, methacryloylamidohistidine-Pt(II) [MAH-Pt(II)] has used as a new metal-chelating monomer via metal coordination-chelation interactions and cholic acid. Nanoshell sensors with templates give a cavity that is selective for cholic acid. The cholic acid can simultaneously chelate to Pt(II) metal ion and fit into the shape-selective cavity. Thus, the interaction between Pt(II) ion and free coordination spheres has an effect on the binding ability of the gold-silver-nanoclusters nanosensor. The binding affinity of the cholic acid imprinted nanoparticles have investigated by using the Langmuir and Scatchard methods and determined affinity constant (Kaffinity) has found to be 2.73 × 10 mol Land 2.13 × 10 mol L, respectively. At the last step of this procedure, cholic acid level in blood serum and urine which belong to a healthy people were determined by the prepared gold-silver- nanoclusters.
Source: Talanta, Available online 2 March 2012
Aytaç Gültekin, Arzu Ersöz, Adil Denizli, Rıdvan Say
Molecular imprinted polymers (MIPs) as a recognition element for sensors are increasingly of interest and MIP-nanoparticles have started to appear in the literature. In this study, we have proposed a novel thiol ligand-capping method with polymerizable methacryloylamido-cysteine (MAC) attached to gold-silver-nanoclusters reminiscent of a self-assembled monolayer and have reconstructed surface shell by synthetic host polymers based on molecular imprinting method for cholic acid recognition. In this method, methacryloylamidohistidine-Pt(II) [MAH-Pt(II)] has used as a new metal-chelating monomer via metal coordination-chelation interactions and cholic acid. Nanoshell sensors with templates give a cavity that is selective for cholic acid. The cholic acid can simultaneously chelate to Pt(II) metal ion and fit into the shape-selective cavity. Thus, the interaction between Pt(II) ion and free coordination spheres has an effect on the binding ability of the gold-silver-nanoclusters nanosensor. The binding affinity of the cholic acid imprinted nanoparticles have investigated by using the Langmuir and Scatchard methods and determined affinity constant (Kaffinity) has found to be 2.73 × 10 mol Land 2.13 × 10 mol L, respectively. At the last step of this procedure, cholic acid level in blood serum and urine which belong to a healthy people were determined by the prepared gold-silver- nanoclusters.
Highlights
► Molecular imprinting is a technology to create recognition sites in a macromolecular matrix ► MIPs are easy to prepare, stable, inexpensive and capable of molecular recognition ► A nanocluster is an amorphous/semicrystalline nanostructure ► We have combined nanoscale materials with MIP.Improving methodological aspects of the analysis of five regulated haloacetic acids in water samples by solid-phase extraction, ion-pair liquid chromatography and electrospray tandem mass spectrometry
03 March 2012, 22:45:49
Publication year: 2012
Source: Talanta, Available online 2 March 2012
M.C. Prieto-Blanco, M.F. Alpendurada, P. López-Mahía, S. Muniategui-Lorenzo, D. Prada-Rodríguez, ...
Haloacetic acids (HAAs) are organic pollutants originated from the drinking water disinfection process, which ought to be controlled and minimized. In this work a method for monitoring haloacetic acids (HAAs) in water samples is proposed, which can be used in quality control laboratories using the techniques most frequently available. Among its main advantages we may highlight its automated character, including minimal steps of sample preparation, and above all, its improved selectivity and sensitivity in the analysis of real samples. Five haloacetic acids (HAA5) were analysed using solid-phase extraction (SPE) combined with ion-pair liquid chromatography and tandem mass spectrometry. For the optimization of the chromatographic separation, two amines (triethylamine, TEA and dibutylamine, DBA) as ion pair reagents were compared, and a better selectivity and sensitivity was obtained using DBA, especially for monohaloacetic acids. SPE conditions were optimized using different polymeric adsorbents.The electrospray source parameters were studied for maximum precursor ion accumulation, while the collision cell energy of the triple quadrupole mass spectrometer was adjusted for optimum fragmentation. Precursor ions detected were deprotonated, dimeric and decarboxylated ions. The major product ions formed were: ionized halogen atom (chloride and bromide) and decarboxylated ions. After enrichment of the HAAs in Lichrolut EN adsorbent, the limits of detection obtained by LC-MS/MS analysis (between 0.04 and 0.3 ng mL) were comparable to those obtained by GC-MS after derivatization. Linearity with good correlation coefficients was obtained over two orders of magnitude irrespective of the compound. Adequate recoveries were achieved (60%-102%), and the repeatability and intermediate precision were in the range of 2.4-6.6% and 3.8-14.8%, respectively. In order to demonstrate the usefulness of the method for routine HAAs monitoring, different types of water samples were analysed. In swimming pool water samples the ∑HAAs were determined between 76-154 ng mL.
Source: Talanta, Available online 2 March 2012
M.C. Prieto-Blanco, M.F. Alpendurada, P. López-Mahía, S. Muniategui-Lorenzo, D. Prada-Rodríguez, ...
Haloacetic acids (HAAs) are organic pollutants originated from the drinking water disinfection process, which ought to be controlled and minimized. In this work a method for monitoring haloacetic acids (HAAs) in water samples is proposed, which can be used in quality control laboratories using the techniques most frequently available. Among its main advantages we may highlight its automated character, including minimal steps of sample preparation, and above all, its improved selectivity and sensitivity in the analysis of real samples. Five haloacetic acids (HAA5) were analysed using solid-phase extraction (SPE) combined with ion-pair liquid chromatography and tandem mass spectrometry. For the optimization of the chromatographic separation, two amines (triethylamine, TEA and dibutylamine, DBA) as ion pair reagents were compared, and a better selectivity and sensitivity was obtained using DBA, especially for monohaloacetic acids. SPE conditions were optimized using different polymeric adsorbents.The electrospray source parameters were studied for maximum precursor ion accumulation, while the collision cell energy of the triple quadrupole mass spectrometer was adjusted for optimum fragmentation. Precursor ions detected were deprotonated, dimeric and decarboxylated ions. The major product ions formed were: ionized halogen atom (chloride and bromide) and decarboxylated ions. After enrichment of the HAAs in Lichrolut EN adsorbent, the limits of detection obtained by LC-MS/MS analysis (between 0.04 and 0.3 ng mL) were comparable to those obtained by GC-MS after derivatization. Linearity with good correlation coefficients was obtained over two orders of magnitude irrespective of the compound. Adequate recoveries were achieved (60%-102%), and the repeatability and intermediate precision were in the range of 2.4-6.6% and 3.8-14.8%, respectively. In order to demonstrate the usefulness of the method for routine HAAs monitoring, different types of water samples were analysed. In swimming pool water samples the ∑HAAs were determined between 76-154 ng mL.
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