Amines In Environmental Water Samples Research Articles

Determination of aromatic amines in environmental water samples by deep eutectic solvent-based dispersive liquid-liquid microextraction followed by HPLC-UV

This study reports a deep eutectic solvent based dispersive liquid-liquid microextraction (DES-DLLME) to extract aromatic amines (4-chloroaniline, 3-nitroaniline, 2-naphtylamine) in environmental water samples before their HPLC-UV determination. The hydrophobic deep eutectic solvent (DES) was prepared by mixing bis(2-ethylhexyl) phosphate (BEHP) as a hydrogen bond acceptor and phenol as a hydrogen bond donor. Affecting factors on the extraction of the aromatic amines were investigated and optimized. Optimum conditions were: DES type: BHHP-Ph ratio: 1 to 2; pH of solution: 8.0; DES volume: 80 µL, salt amount: 10% (w/v). Under optimum conditions, the developed method showed a wide linear range of 0.2–200 µg L−1 (R2 ≥ 0.99) with satisfactory recoveries (≥90.0%). The limit of detections (LODs) and limit of quantifications (LOQs) were in the range of 0.07–0.17 µg L−1 and 0.2–0.5 µg L−1, respectively. The enrichment factors were 170, 180 and 190 for 4-chloroaninile, 3-nitroaniline, 2-naphtylamine, respectively. Based on obtained results, the proposed method is straightforward, efficient, sensitive, and eco-friendly for the extracting and determining of the aromatic amines in environmental water samples.

A novel assay to measure tertiary and quaternary amines in wastewater: An indicator for NDMA wastewater precursors

This study examined the potential of using a novel bulk amine assay as an approximation for the tertiary and quaternary amine load in wastewaters and surface water samples, and this approximation was compared to N-nitrosodimethylamine (NDMA) formation potential using chloramines. An existing colorimetric method was examined and optimized for the detection of amines in environmental water samples. The method consists of liquid-liquid extraction followed by a catalyzed reaction to form a yet-undefined product that is known to be both a strong chromophore and fluorophore. Previous work verified that this reaction was effectively catalyzed by a number of compounds containing tertiary and quaternary amine moieties. Many tertiary and quaternary compounds are also efficient producers of NDMA under chloramination conditions, and a linear correlation was consequently derived from the bulk amine signals vs. NDMA formation potential in various wastewater samples (R2 = 0.74; n = 24; p-value < 0.05). The results provide evidence that approximately 2% of the tertiary and quaternary amines measured can form NDMA and an estimated 0.01–1.3% of nitrogen in dissolved organic nitrogen originates from these bulk amines. The normalization of NDMA concentration by the amine measurement revealed that ozone effectively destroyed those tertiary and quaternary amine structures more likely to form NDMA in treated wastewater samples. This bulk amine assay illustrates that proxy measurements of tertiary and quaternary amines can be linked to the NDMA formation potential of a given sample, and this approach may prove useful as a characterizing tool for NDMA precursors in wastewater.

Determination of aromatic amines in environmental water samples using solid-phase extraction modified with sodium dodecyl sulphate and micellar liquid chromatography

ABSTRACTExtraction and determination of seven aromatic amines in environmental water samples were performed with solid-phase extraction (SPE) and micellar liquid chromatography (MLC) using experimental design. Extraction of aromatic amines was carried out with a C18 cartridge modified with sodium dodecyl sulphate (SDS). The washing solution and elution solvent for extraction of aromatic amines were aqueous solution containing 5% (v/v) acetonitrile and 5% (v/v) acetone and 3 mL methanol, respectively. The chemometrics approach was applied for the separation optimisation of these compounds using MLC. Different mobile phase compositions were used for modelling based on retention times to obtain the best separation using central composite design. The optimum mobile phase composition for separation and determination of analytes in water samples was 69 mM SDS, 9% v/v 1-propanol and pH = 6.4. Recoveries were between 84.8–93.5% with relative standard deviation (RSD) less than 5.8% (n = 5). Limits of detection and linear range were 1–4.5 and 3.1–125.0 µg/L, respectively. The proposed method was applied to determine the aromatic amines in real samples (river and well waters). Amount of 4-nitroaniline and 3-nitroaniline in river water sample were 2.15 and 1.91 µg/L, respectively.

Preparation of a mixed-mode silica-based sorbent by click reaction and its application in the determination of primary aromatic amines in environmental water samples

Download options Please wait... Article information DOI https://doi.org/10.1039/C3AY42027B Article type Paper Submitted 14 Nov 2013 Accepted 15 Jan 2014 First published 16 Jan 2014 Download Citation Anal. Methods, 2014,6, 2102-2111 BibTex EndNote MEDLINE ProCite ReferenceManager RefWorks RIS Permissions Request permissions Preparation of a mixed-mode silica-based sorbent by click reaction and its application in the determination of primary aromatic amines in environmental water samples Y. Zhu, W. Zhang, L. Li, C. Wu and J. Xing, Anal. Methods, 2014, 6, 2102 DOI: 10.1039/C3AY42027B To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page. If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given. If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page. Read more about how to correctly acknowledge RSC content. Social activity Tweet Share Search articles by author Yuling Zhu Weiya Zhang Lixia Li Caiying Wu Jun Xing

Simultaneous derivatization and air-assisted liquid–liquid microextraction of some aliphatic amines in different aqueous samples followed by gas chromatography-flame ionization detection

The paper presents a new method based on simultaneous derivatization and air-assisted liquid–liquid microextraction (AALLME) for the extraction and preconcentration of some aliphatic amines prior to gas chromatography-flame ionization detection (GC-FID). Primary aliphatic amines are derivatized and extracted simultaneously by a fast reaction with butylchloroformate (derivatization agent/extraction solvent) under mild conditions. The mixture of butylchloroformate and aqueous sample solution is rapidly sucked into a 10-mL glass syringe and then is injected into a test tube with conical bottom and the procedure is repeated seven times. After centrifuging the resulted cloudy solution, the derivatized analytes in the sedimented phase are determined by GC-FID. The influence of main factors on the efficiency of derivatization/extraction procedure is studied. Under the optimal conditions, the enrichment factors (EFs) for aliphatic amines are obtained in the range of 248–360 and limits of detection (LODs) are between 0.30 and 2.6μgL−1. The obtained extraction recoveries ranged from 50 to 72% and the relative standard deviation (RSD) was less than 4.8% for intra-day (n=6) and inter-days (n=4) precision. The method is successfully applied to determine some aliphatic amines in environmental water samples.

A method based on microextraction by packed sorbent-programmed temperature vaporizer–fast gas chromatography–mass spectrometry for the determination of aromatic amines in environmental water samples

We report a sensitive method for the determination of 15 aromatic amines in environmental water samples. They have been included in the list of priority pollutants in surface water by the European Union. The method is based on analyte enrichment using microextraction by packed sorbent (MEPS) and later analysis using programmed temperature vaporizer-gas chromatography-mass spectrometry (PTV-GC-MS). All MEPS steps were carried out manually. The detection limits were of the order of nanograms per liter for most of the compounds. The results were compared with those obtained without MEPS using the method exclusively based on direct injection of the sample into the PTV-GC-MS. External calibration in ultrapure water was used in the determination of the compounds studied in five types of water samples (sea, river, tap, influent, and effluent waste water) since no significant matrix effect was found. The results obtained can be considered highly satisfactory and they revealed the presence of aniline in the sea and the influent and effluent waste water samples.

Development of a vortex-assisted ionic liquid microextraction method for the determination of aromatic amines in environmental water samples

A vortex-assisted ionic liquid microextraction method coupled with ultra fast liquid chromatographic separation and detection was developed for the analysis of three aromatic amines, 4-chloroaniline, 1-naphthylamine and 4-aminobiphenyl, in environmental water samples. 1-Hexyl-3-methylimidazolium hexafluorophosphate [C6MIM][PF6] was used as the extraction solvent as it can disperse in water completely and quickly with the aid of vortex mixing. A dispersive solvent was not required. Several parameters such as type and volume of extraction solvent, vortex velocity, extraction time, centrifugation time, pH of sample solution and ionic strength in sample solution were investigated. Under the optimized conditions, the intra-day and inter-day precision of the proposed method were 2.3–3.5% (n = 5) and 2.8–5.3% (n = 5), respectively. The limits of detection and quantification were in the range of 0.24–0.57 μg L−1 and 0.80–1.90 μg L−1, respectively. The proposed method was applied in the determination of three aromatic amines in several real water samples. Acceptable recoveries of the analytes, ranging from 79% to 111% (the relative standard deviations ≤6.0%), were obtained.

Optimization of simultaneous derivatization and extraction of aliphatic amines in water samples with dispersive liquid–liquid microextraction followed by HPLC

Dispersive liquid-liquid microextraction based on solidification of floating organic droplet (DLLME-SFO) with simultaneous derivatization followed by high-performance liquid chromatography-diode array detection (HPLC-DAD) was applied for preconcentration and determination of primary and secondary aliphatic amines in environmental water samples. A ternary mixture consisting of a disperser, an extractant and a derivatization reagent was used for the simultaneous derivatization and extraction of aliphatic amines in different water samples. The effects of various experimental parameters on derivatization and extraction efficiency were studied simultaneously using experimental design. A Plackett-Burman design was performed for screening of variables in order to determine the significant variables affecting the extraction efficiency. Then, the significant factors were optimized by using a Box-Behnken design (BBD) and the response surface equations were derived. Under optimal conditions, the preconcentration factors were between 210 and 290. The limit of detections (LODs) ranged from 0.005 to 0.02 μg/L and dynamic linear ranges (DLRs) of 0.05-500 and 0.1-500 μg/L were obtained for most of analytes. The performance of the method was evaluated for extraction and determination of primary and secondary aliphatic amines in environmental water samples in micrograms per liter and satisfactory results were obtained (RSDs <12.5%).

Dispersive liquid phase micro-extraction of aromatic amines in environmental water samples

A new, rapid and sensitive method for the determination of aromatic amines such as o-nitroaniline (NIT), alpha-naphtylamine (NAP), o-chloroaniline (CHL) in environmental water samples was developed with dispersive liquid phase micro-extraction coupled with high performance liquid chromatography. Preliminary experiments indicated that excellent achievements were obtained when chlorobenzene and acetonitrile were employed as the extraction solvent and dispersive solvent, respectively. Some other parameters that would have important effect on the pre-concentration of aromatic amines were investigated in detail. Under the optimal conditions, the method had excellent linear relationship between the peak area and the concentration for NIT, NAP and CHL in the concentration range of 1 ∼ 50 µg L−1. The limits of detection and precisions of the proposed method were in the range of 0.1 ∼ 0.7 µg L−1 and 6.3 ∼ 9.7%, respectively. The proposed method has been validated with two real water samples, and the results showed that excellent spiked recoveries in the range of 92.8% ∼ 111.5% were achieved. All these demonstrated that the proposed method would be very useful and applicable for the determination of such pollutants in the future.

Ionic Liquid-Based Submerged Single Drop Microextraction: a New Method for the Determination of Aromatic Amines in Environmental Water Samples

A novel microextraction method termed ionic liquid-based submerged single drop microextraction combining liquid chromatography (LC) was developed for the determination of aromatic amines in environmental water samples. This method is simple and rapid for the determination of three aromatic amines (2-nitroaniline, 3-chloroaniline and 4-bromoaniline) which were selected as model compounds for validation of this new mode of microextraction. This technique combines extraction and preconcentration of the analytes in one step before determination by LC-UV, and the ionic liquid was used instead of the organic solvent as extractant. Several important parameters influencing the extraction efficiency such as the volume of the aqueous sample solution (donor phase), extraction time, pH of the donor phase and salt effect were investigated. Under the optimized conditions, acceptable enrichment factors (132–186) and relative recoveries (82–98%) were obtained for the extraction of the target analytes in real water samples. The calibration curves were linear with correlation coefficients ranging from 0.9983 to 0.9989 and RSDs (n = 5) of 4.9–6.8%. The LODs for the three aromatic amines were 1–2.5 μg L−1 at a signal-to-noise ratio (S/N) of 3.

Development and validation of a hydrophilic interaction liquid chromatographic method for determination of aromatic amines in environmental water

A simple, precise, and accurate hydrophilic interaction liquid chromatographic (HILIC) method has been developed for the determination of five aromatic amines in environmental water samples. Chromatography was carried out on a bare silica column, using a mixture of acetonitrile and a buffer of NaH(2)PO(4)-H(3)PO(4) (pH 1.5, containing 10mM NaH(2)PO(4)) (85:15, v/v) as a mobile phase at a flow rate of 1 mL min(-1). Aromatic amines were detected by UV absorbance at 254 nm. The linear range of amines was good (r(2)>0.998) and limit of detection (LOD) within 0.02-0.2 mg L(-1) (S/N=3). The retention mechanism for the analytes under the optimum conditions was determined to be a combination of adsorption, partition and ionic interactions. The proposed method was applied to the environmental water samples. Aromatic amines were isolated from aqueous samples using solid-phase extraction (SPE) with Oasis HLB cartridges. Recoveries of greater than 75% with precision (RSD) less than 12% were obtained at amine concentrations of 5-50 microg L(-1) from 100mL river water and influents from a wastewater treatment plant (WWTP). The present HILIC technique proved to be a viable method for the analysis of aromatic amines in the environmental water samples.

Simultaneous conduction of two- and three-phase hollow-fiber-based liquid-phase microextraction for the determination of aromatic amines in environmental water samples

This paper describes a simultaneously performed two-/three-phase hollow-fiber-based liquid-phase microextraction (HF-LPME) method for the determination of aromatic amines with a wide range of p K a (−4.25 to 4.6) and log K OW (0.9–2.8) values in environmental water samples. Analytes including aniline, 4-nitroaniline, 2,4-dinitroaniline and dicloran were extracted from basic aqueous samples (donor phase, DP) into the microliter volume of organic membrane phase impregnated into the pores of the polypropylene hollow fiber wall, then back extracted into the acidified aqueous solution (acceptor phase, AP) filling in the lumen of the hollow fiber. The mass transfer of the analytes from the donor phase through the organic membrane phase into acceptor phase was driven by both the counter-coupled transport of hydrogen ions and the pH gradient. Afterwards, the hollow fiber was eluted with 50 μL methanol to capture the analytes from both the organic membrane and the acceptor phase. Factors relevant to the enrichment factors (EFs) were investigated. Under the optimized condition (DP: 100 mL of 0.1 M NaOH with 2 M Na 2SO 4; organic phase: di- n-hexyl with 8% trioctylphosphine oxide (TOPO); AP: 10 μL of 8 M HCl; extraction time of 80 min), the obtained EFs were 405–2000, dynamic linear ranges were 5–200 μg/L ( R > 0.9976), and limits of detection were 0.5–1.5 μg/L. The presence of humic acid (0–25 mg/L dissolved organic carbon) had no significant effect on the extraction efficiency. The proposed procedure worked very well for real environmental water samples with microgram per liter level of analytes, and good spike recoveries (80–103%) were obtained.

Continuous solid-phase extraction and dansylation of low-molecular-mass amines coupled on-line with liquid chromatography and peroxyoxalate chemiluminescence-based detection

An on-line liquid chromatographic system involving solid-phase extraction, dansylation and peroxyoxalate chemiluminescence-based detection was used to determine low-molecular-mass amines in environmental water samples. Sample volumes of 50 ml were enriched in the amines by passage through an IRC-50 cation-exchange column, elution and on-line derivatization with 0.16 M borate buffer (pH 11) and dansyl chloride, respectively, to a C 18 analytical column, and determined by using an integrated derivatization-chemiluminescence detection unit based on the bis(2,4,6-trichlorophenyl)oxalate–hydrogen peroxide system. Dynamic ranges from 60 ng l −1 to 400 μg l −1, limits of detection at the nanogram-per-litre level and relative standard deviations from 2.2 to 5.0% were thus obtained for the amines. The proposed method surpasses other chromatographic alternatives based on different detection techniques in terms of limits of detection. Also, it affords routine analyses of environmental waters containing low-molecular-mass amines at trace levels.