ЖУРНАЛ АНАЛИТИЧЕСКОЙ ХИМИИ, 2015, том 70, № 11, с. 1208-1218
ОРИГИНАЛЬНЫЕ СТАТЬИ
УДК 543
DETERMINATION OF POLYBROMINATED DIPHENYL ETHERS IN WATER AT ng/L LEVEL BY A SIMPLE DLLME-GC-(EI) MS METHOD
© 2015 Monica S.F. Santos*, José Luis Moreira**, Luis M. Madeira*, Arminda Alves*, 1
*LEPABE, Faculty of Engineering of the University of Porto Rua Dr. Roberto Frias, 4200-465 Porto, Portugal 1E-mail: aalves@fe.up.pt **Department of Chemical Engineering, Faculty of Engineering of the University of Porto Rua Dr. Roberto Frias, 4200-465 Porto, Portugal Received 04.07.2013; in final form 09.03.2015
Dispersive liquid—liquid microextraction (DLLME) is an extraction procedure gaining popularity in the recent years due to the easiness of operation, high enrichment factors, low cost and low consumption of organic solvents. This extraction method, prior to gas chromatography with mass spectrometry detection (GC—MS), was optimized for the analysis of polybrominated diphenyl ethers (PBDEs) in aqueous samples. These were extracted with chlorobenzene (extraction solvent) and acetonitrile (dispersive solvent), allowing an enrichment factor of about 470 for BDE-100. The calibration curve for BDE-100 was linear in the range of 0.005—10 p.g/L, with an average reproducibility of 12% (RSD, %). The LOD, calculated by the signal-to-noise ratio, was 0.5 ng/L for BDE-100 and the recovery ranged from 91—107% for all spiked samples. Relative expanded uncertainty was concentration-dependent, reaching high values near the limit of quantification and decreasing until 14% for concentrations higher than 1 p.g/L of BDE-100. The dispersive liquid—liquid microextraction combined with gas chromatography with mass spectrometry detection (DLLME—GC—MS) method could be successfully applied to the determination of other PBDEs in water samples.
Keywords: dispersive liquid—liquid microextraction, gas chromatography with mass spectrometry detection, polybrominated diphenyl ethers, uncertainty.
DOI: 10.7868/S0044450215110134
PBDEs are widely used in commercial products such as furniture, textiles, plastics, paints and electronic equipments to reduce ignition and burning, acting as additive flame retardants due to their low cost and high-performance. The family of PBDEs consists of 209 congeners (C12H10 _ xBrxO where x = 1, 2, ..., 10). The main commercial mixtures, penta-, octa-and deca-BDE, contain a limited number of congeners, respectively BDE-99/47/100/153/154, BDE-183/197/196/207 and BDE-209/206, in order of decreasing percentage [1]. These commercial mixtures differ in the content of specific PBDEs congeners, which in turn differ in their bioavailability, bioaccumulation and toxicological properties. As they are not chemically bound, these chemicals can leach out of the products/materials in which they are applied. As a result of their potential to accumulate in the environment, the EU has agreed to ban the marketing and use of penta- and octa-BDE from 1 July 2004. Only deca-BDE is allowed, and therefore EU and USA industries have ceased the penta- and octa-BDE manufacturing. There is however no maximum admissible level for
these compounds in water set by the European Community.
Analytical methods for PBDEs in waters are complex and laborious, due to the necessity of using a pre-concentration step. This pre-concentration step is always needed in order to reach detection limits (LODs) low enough to determine the ultra-trace levels at which PBDEs are present in water (normally within the ng/L or low ^g/L range) [2—4]. The analytical methods found in the literature for PBDEs quantification in water matrices are compiled in Table 1 [5—18]. Concerning the chromatographic techniques, gas chro-matography with electron-capture detection (ECD) [7] or mass spectrometry detection [9, 10, 14—18] are the most widely used for the determination of PBDEs in water samples, but high-performance liquid chromatogra-phy with diode array (HPLC-DAD), ultraviolet or MS detectors may be also applied [5, 6, 8, 11—13]. Methods that use liquid chromatography generally lead to higher LODs (10-700 ng/L). The LLE-HPLC-MS/MS method conducts to lower LODs but the equipment is rather expensive, a high sample volume is required (1 L) and significant amounts of organic solvents (not environ-
Table 1. Literature survey on PBDEs quantification in water samples
Analytes Extraction Determination Analytical parameters Uncertainty Year Ref.
BDEs 47, 99, 154, 183 TA-IL-DLLME Sample volume 5 mL, dispersive solvent MeOH (1 mL), extraction solvent [C8MIM] [PF6] (40 ^L) HPLCDAD LR 500-500000 ng/L, RSD 1.0-3.8%, LOD 100-400 ng/L, recovery - 81.0-127.1% No 2012 [5]
BDEs 28, 47, 99, 154, 183, 209 SFOME Sample volume 40 mL, extraction solvent 2-dodecanol (25 p.L), 60°C, stirring speed 900 rpm, extraction time 25 min, salt addition — no HPLCDAD LR 5000-500000 ng/L (BDE-209), 500-75000 ng/L (others); LOD 10-40 ng/L; recovery 92-118% No 2012 [6]
BDEs 28, 47, 85, 99, 100, 153, 154 SPE Column Supelclean LC-C18; conditioning DCM (2 mL), MeOH (5 mL), H2O (5 mL); load 100 mL at 10 mL/min; elution K-hexane (2 mL) + DLLME Sample volume 5 mL, disperser solvent ACN (1 mL), extraction solvent 1,1,2,2-tetrachloroethane (22 pL), salt addition — no GC-ECD LR 0.1-100 ng/L (BDEs 28, 47), 0.5-500 ng/L (others); RSD 4.2-7.9%; LOD 0.030-0.15 ng/L; recovery 66.8-94.1% No 2009 [7]
BDEs 47, 99, 100, 153, 154 LLE Sample volume 1 L, extraction solvent K-hexane (100 mL), salt addition 20 g LC/NI-APP1-MS/MS LR 0.025-10 ng/L, LOD 0.004-0.1 ng/L, recovery 43-99% No 2009 [8]
BDEs 47, 99, 100, 153 USAEME Sample volume 10 mL, temperature 35°C, extraction solvent CF (100 p.L), extraction time 5 min GC-MS LR 5-5000 ng/L (BDEs 47, 100), 5-10000 ng/L (BDEs 99,153); RSD < 10.3%; LOD 1-2 ng/L;recovery > 96% No 2009 [9]
BDEs 47, 99, 100, 153 CPE Sample volume 10 mL, non-ionic surfactant Triton X-100 (0.4 g/L), salt addition 400 ^L of 6.15 M, 80°C, equilibrium time 7 min+UABEEx-traction solvent isooctane (50 p.L), extraction time 5 min GC-MS LR 4-150 ng/L, RSD < < 8.5%, LOD 1-2 ng/L, recovery 96-106% No 2009 [10]
BDEs 28, 47, 99, 209 DLLME Sample volume 5 mL, disperser solvent ACN (1 mL), extraction solvent tetrachloroethane (20 p.L), salt addition — no HPLCDAD LR 50-50 000 ng/L (BDEs 28, 99), 100-100000 ng/L (others); RSD 3.8-6.3%; LOD 12.4-55.6 ng/L; recovery 87.0-114.3% No 2008 [11]
BDE-209 DLLME Sample volume 5 mL, disperser solvent THF (1 mL), extraction solvent tetrachloroethane (22 pL), salt addition — no HPLC-UV LR 1000-500000 ng/L, RSD 2.1%, LOD 200 ng/L, recovery 89.9-95.8% No 2008 [12]
BDE-209 SDME Sample volume 5 mL, extraction solvent toluene, solvent drop volume 3 p.L, extraction time 15 min, stirring speed 600 rpm, salt addition — no HPLCDAD LR 1000-1000000 ng/L, RSD 4.8%, LOD 700 ng/L, recovery 91.5-102.8% No 2007 [13]
BDEs 28, 47, 99, 100 HF-LPME Sample volume 3 mL, 40°C, extraction solvent decane, stirring speed 1000 rpm, extraction time 20 min, salt addition — no GC-ICP-MS LR 200-20000 ng/L, RSD 5.1-9.1%, LOD 15.2-40.5 ng/L, recovery 85-110% No 2007 [14]
BDEs 28, 47, 99, 100, 153, 154, 183 HF-MMLLE Sample volume 100 mL, extraction solvent K-undecane, stirring speed 1200 rpm, extraction time 60 min, salt addition — no GC-MS LR 1-100 ng/L, RSD 16.9%, LOD 1.1 ng/L, recovery 85-110% No 2006 [15]
Table 1. (Contd.)
Analytes Extraction Determination Analytical parameters Uncertainty Year Ref.
BDEs 28, 47, 66, 85, 99, 100, 138, 153, 154 MAE Sample volume 1.5 L, extraction solvent hexane—acetone (1 : 1, v/v) (60 mL), 85°C, extraction time 1 min; two cycles GC—MS/MS LR 500-100000 ng/L, LOD 0.02-0.1 ng/mem-brane,recovery 72-91% No 2006 [16]
BDEs 28, 47, 66, 85, 99, 100, 138, 153, 154 SBSE Sample volume 100 mL, PDMS commercial stir bars, temperature ambient, extraction time 25 h, MeOH addition 20% TD-GC-MS LR 20-600 ng/L, RSD < 20%, LOD 0.3-9.6 ng/L, recovery 94-106% No 2006 [17]
BDEs 3, 47, 85, 99, 100, 153, 154 HS-SPME Sample volume 10 mL, fiber PDMS, extraction temperature 100°C, extraction time 30 min, desorption temperature 280°C, desorption time 2 min, salt addition — no GC-MS-MS LR 0.12-503 ng/L, RSD 1.2-26%, LOD 0.0075-0.190 ng/L, recovery 74-117% No 2004 [18]
Notations: AC — acetone, ACN — acetonitrile, CB — chlorobenzene, CF — chloroform, CPE — cloud point extraction, CTC — carbon tetrachloride, DCM — dichloromethane, DLLME — dispersive liquid—liquid microextraction, EF — enrichment factor, ER — extraction recovery, GC-ECD — gas chromatography with electron capture detector, GC—ICP-MS — gas chromatography—inductively coupled plasma mass spectrometry, GC—MS — gas chromatography mass spectrometry, GC—MS/MS — gas chromatography tandem mass spectrometry, HF-LPME — hollow-fiber liquid phase microextraction, HF-MMLE — hollow-fiber microporous membrane liquid—liquid extraction, HPLC-DAD — high-performance liquid chromatography with diode array detector, HPLC-UV — high-performance liquid chromatography with ultraviolet detector, HS-SPME — headspace solid phase microextraction, LC/NI-APPI—MS/MS — liquid chro-matography-negative ion atmospheric pressure photoionization tandem mass spectrometry, LLE — liquid—liquid extraction, LOD — detection limit, LOQ — limit of quantification, LR — linearity range, MAE — microwave assisted extraction, MeOH — methanol, PBDEs — polybrominated diphenyl ethers, RSD — relative standard deviation, SBSE — stir bar sorptive extraction, SDME — single-drop microextraction, SFOME — solidified floating organic drop microextraction, SPE — solid phase extraction, TA-IL-DLLME — temperature-assisted ionic liquid dispersive liquid—liquid microextraction, TCE — 1,1,2,2-tetrachloroetahne, TD-GC—MS — thermal desorption gas chromatography mass spectrometry; TOC — total organic carbon; UABE — ultrasound-assisted back extraction; USAEME — ultrasound-assisted emulsification-microextraction.
mentally friendly) are typically used, which restrains this method for monitoring applications.
Solid p
Для дальнейшего прочтения статьи необходимо приобрести полный текст. Статьи высылаются в формате PDF на указанную при оплате почту. Время доставки составляет менее 10 минут. Стоимость одной статьи — 150 рублей.