ANALYTICAL CHEMISTRY
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2016
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IF 5.886
Zhongmin Feng,Peng Zhu,Hongtao Fan,Shanshan Piao,Liang Xu,Ting Sun
We evaluated the possibility of sampling dissolved orthophosphate using the diffusive gradient in thin films (DGT) technique with a phosphate ion-imprinted polymer (PIP)-based adsorbent and assessed the effect of biofilm on the DGT measurement. The composition of biofilm formed on the DGT surface was analyzed, and the effect of biofouling on the diffusion coefficient of the analyte was investigated. The corrected diffusion coefficient for the biofouled DGT was estimated and used for the calculation of the DGT equation. PIP-binding gels had a higher adsorption affinity for orthophosphate than for the other anions, indicating its selectivity for orthophosphate. The concentrations predicted via DGT agreed well with the concentrations determined in the bulk solutions. Sampling of orthophosphate using PIP-DGT was consistent over a pH range of 3–9 and ionic strength range of 0.01–10 000 μM. Other P compounds cannot be measured using the PIP-DGT technique. The diffusion coefficient of the orthophosphate linearly decreased with increasing thickness of the biofilm. This sampling method performed predictably in freshwater when the biofilm was not formed or when value for the biofilm interference was reduced by using the corrected diffusion coefficient.
研究领域:
环境科学
·
分析化学
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DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2018
·
IF 6.042
Yi-Tao Zou,Zhou Fang,Yuan Li,Runmei Wang,Hao Zhang,Kevin C. Jones,Xin-Yi Cui,Xin-Yao Shi,Daixia Yin,Chao Li,Zhao-Dong Liu,Lena Q. Ma,Jun Luo
Widespread use of organophosphorus flame retardants (OPFRs) and their ubiquity in water results in the need for a robust and reliable monitoring technique to better understand their fate and environmental impact. In situ passive sampling using the diffusive gradients in thin-films (DGT) technique provides time-integrated data and is developed for measuring OPFRs here. Ultrasonic extraction of binding gels in methanol provided reliable recoveries for all tested OPFRs. Diffusion coefficients of TCEP, TCPP, TDCPP, TPrP, TBP, and TBEP in the agarose diffusive gel (25 °C) were obtained. The capacity of an HLB binding gel for OPFRs was >115 μg per disc, and the binding performance did not deteriorate with time up to 131 days. DGT performance is independent of typical environmental ranges of pH (3.12–9.71), ionic strength (0.1–500 mmol L–1), and dissolved organic matter (0–20 mg L–1), and also of diffusive layer thickness (0.64–2.14 mm) and deployment time (3–168 h). Negligible competition effects between OPFRs was found. DGT-measured concentrations of OPFRs in a wastewater treatment plant (WWTP) effluent (12–16 days) were comparable to those obtained by grab sampling, further verifying DGT’s reliability for measuring OPFRs in waters.
研究领域:
环境科学
·
分析化学
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PubMed
高影响因子
ANALYTICAL CHEMISTRY
·
2020
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IF 6.785
Wen Fang,Xinyao Shi,Danxing Yang,Xuan Hu,Paul N. Williams,Bingqing Shi,Zhaodong Liu,Jun Luo
In situ monitoring of Sb speciation improves the understanding of Sb biogeochemistry and toxicity in ecosystems. Precise measurement of Sb is a challenge due to its instability of oxidation and ultratrace concentration. The development of simple and reliable methods specific to SbIII measurement is not only appealing but essential for implementing regulations. Here, we present an in situ speciation analysis method for SbIII, using the diffusive gradients in thin films (DGT) technique, combined with mercapto-functionalized SBA-15 mesoporous silica nanoparticles (MSBA). Laboratory performance tests confirmed MSBA-DGT uptake was independent of pH (4–9) and ionic strength (0.1–200 mmol L–1). DGT devices equipped with MSBA-based binding gels showed a theoretically linear accumulation of SbIII and exhibited a high capacity for SbIII at 65 μg/gel disc, with negligible accumulation of SbV over a 72 h deployment. Compared with commercial 3-mercaptopropyl-functionalized silica (MFS), the nanosized MSBA facilitate its even distribution in the binding gels. Furthermore, the good selectivity and high homogeneity of the MSBA gel enabled it to be applied in a rice rhizosphere in conjunction with AgI gel to investigate the effects of sulfur application on the SbIII solubility. In summary, the newly developed MSBA-DGT provides a selective measurement of SbIII, showing potential for environmental monitoring and further application in understanding the biogeochemical process of Sb.
研究领域:
环境科学
·
生物地球化学
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DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2023
·Vol. 30
·期 17
·51061-51074
·
IF 5.8
Zheng Siheng,Sheng Feng,Gu Cheng,Li Yanying,Fang Zhou,Luo Jun
Triazines are frequently detected in nature water and agricultural soils worldwide. They are considered harmful to plants, animals, and the human health. In this study, diffusive gradients in thin films (DGT) method was developed for the assessment of several triazines. DGT device was used for the in situ measurement of atrazine in a pesticide factory and obtained reliable data. The atrazine concentrations measured by DGT, and solvent extraction method was in a constant ratio. The DIFS model was coupled with DGT technique to study the desorption kinetics of atrazine in four kinds of different soils. The yellow–brown soil was more inclined to adsorb atrazine than other three soils. 2_D DIFS model was used to obtain the partition coefficient for labile atrazine ( K dl ), the values of the response time ( T c ), and desorption/adsorption rates ( k 1 and k −1 ). The yellow–brown soil has a larger labile pool size, and a faster resupply speed of atrazine. The 1_D DIFS model was used to simulate the profiles of atrazine concentrations in soil solution and solid phase. The results show that the desorption of atrazine in soil was limited by kinetic limitation at short time, and was limited by the solid phase reservoir at long time.
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高影响因子
ANALYTICA CHIMICA ACTA
·
2026
·
IF 6.1
Xianghua Wu,Dongjun Li,Haiying Lin,Qingge Feng,Lixin Huang,Qiuyan Hu,Chun Lv,Jie He,Guanjian He
A homogeneous membrane enabled Hg(II) capture and trace-level Hg(II) determination. • S- and N-containing groups dominated Hg(II) binding with a capacity of 639.12 mg/g. • The assembled DGT achieved superior performance with additional correction. • Field trials in coastal aquaculture area yielded Hg(II) concentrations of 1.24–2.62 ng/L. Background Mercury is highly toxic. Hg(II) methylation produces methylmercury, which biomagnifies in aquatic food webs and poses neurological risks. Grab sampling may not represent average labile Hg(II) concentrations during deployment in estuarine and coastal aquaculture waters. Diffusive gradients in thin films (DGT) provides time-integrated measurements, but matrix interference and ion-dependent corrections limit some binding phases. Reliable monitoring requires a matrix-tolerant binding phase. Results A homogeneous thiol-functionalized chitosan membrane (CS-MSA/PVA) was fabricated as a DGT binding layer. The membrane exhibited a maximum Hg(II) capacity of 639.12 mg/g and high affinity at trace levels, with S- and N-containing sites jointly participating in binding. CS-MSA/PVA@DGT achieved 99.0–100.5% elution within 20 min using HCl-thiourea. Hg(II) was measured by hydride generation-atomic fluorescence spectrometry (HG-AFS). The method blank and LOD were 0.45 ± 0.094 ng and 0.28 ng/disc. Hg(II) accumulated linearly in ultrapure water, river water and seawater, with effective diffusion coefficients of 17.9, 16.8 and 16.2 × 10 −6 cm 2 /s, respectively. C DGT /C SOL remained within 0.90–1.10 across pH 3.6–9.6, ionic strength 0–800 mmol/L, fulvic acid below 25 mg/L, major seawater ions, and Mg 2+ /Cl − gradients, requiring no Mg 2+ or Cl − correction. Static and stepwise dynamic spike-recovery tests confirmed time-weighted average Hg(II) determination in river water and seawater ( C DGT /C SOL = 0.91–1.08). After temperature and diffusive boundary layer correction, field DGT-labile Hg(II) concentrations were 1.24–2.62 ng/L, agreeing with purge-trap HG-AFS measurements within 10% deviation. Significance The homogeneous membrane combines efficient Hg(II) capture and quantitative elution with tolerance to coastal water matrices. CS-MSA/PVA@DGT supports labile Hg(II) monitoring and assessment of Hg exposure and aquaculture water quality. Download: Download high-res image (455KB) Download: Download full-size image
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高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2025
·
IF 11.3
Yixuan Liang,Hanbing Li,Yaming Li,Lei Yan,Sumei Li,Xiaowei Wang,Danyang Li,Sha Chen
Environmental challenges of antibiotics contamination have emerged to address severe impacts on ecological stability and human health. Active sampling methods are not well-fitted to study the emerging pollutants since complicated and unstable enrichment devices/chemicals are significantly required for measurements. Diffusive gradients in thin-films (DGT) are proved to be useful for organic compound detection, but limited by its non-specificity for quinolones (QNs) and tetracyclines (TCs) in waters. Consequently, a metal-organic framework derived carbon specific to QNs and TCs was used as binding agent to develop selective DGT (qt-DGT) in this study. qt-DGT had highly selective adsorption capacity for QNs at 85.45–112.59 μg and TCs at 79.19–85.92 μg in a pH range of 4–9 and ionic strength from 0.001 to 0.05 M. Masses of antibiotics accumulated by qt-DGT increased linearly with time in 24 h. After the deployment in a wastewater treatment plant (WWTP) of Beijing, the qt-DGT exhibited stable and selective uptake of QNs and TCs in comparison with traditional HLB-DGT and active sampling methods. With qt-DGT measurements, QNs and TCs up to 1202.3 ng/L from influent forced WWTP became the major sink of antibiotics, and 830.1–966.3 ng/L from effluent warned the inefficient treatment leading to elevated threats on natural waters.
研究领域:
环境科学
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分析化学
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污染物监测
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水处理
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药物代谢
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生态毒理学
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PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2023
·
IF 9.8
Fan Dong,Fan Ge,Xinting Zhao,Daming Sun,Suyu Ren,Yan Wang,Feng Tan
Extensive use of per- and polyfluoroalkyl substances (PFASs) has resulted in their widespread presence in natural waters. Concern for public health requires reliable measurement methods for determining their distribution and risks. Here, a sampling method based on diffusive gradients in thin films (DGT) was developed for measuring PFASs in drinking water sources. Fluorinated graphite (FG) particles were used to prepare the DGT binding gel for selective enrichment of trace PFASs in an aqueous environment. The FG-DGT method did not show sensitivity to relevant environmental parameters including pH (5.0–9.0), ionic strength (0.001–0.5 M), or DOM concentration (0–30 mg/L). The FG-DGT had enough capacity for deployment of up to four months. Six traditional and emerging PFASs including PFOS, PFOA, PFHpA, PFHxS , PFNA, and 6:2 FTSA at the ng/L level were detected in two major reservoirs serving as public drinking water sources by FG-DGT method coupled with liquid chromatography tandem mass spectrometry (LC-MS/MS). PFOA appeared at the highest observed concentrations in the drinking water sources. The research demonstrates that FG-DGT is an effective and efficient tool for monitoring PFASs in drinking water.
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高影响因子
ENVIRONMENTAL GEOCHEMISTRY AND HEALTH
·
2026
·Vol. 48
·期 5
·227
·
IF 4.3
Zeng Yue,Liu Zhennan,Jiang Yajie,Li Yunqin,Yu Wei,Yu Rong,Xu Xiang,Xiao Meiling
Arsenic (As), particularly in its bioavailable species of inorganic As(Ⅲ) known for its significant toxicity and mobility, is a carcinogenic risk to humans. Serving as an innovative analytical tool, the diffusive gradients in thin films (DGT) technique facilitates on-site detection of bioavailable metals. However, the options of DGT binding gels tailored for As(Ⅲ) detection remain elusive. This study undertook the modification of tetraethyl orthosilicate with a 3-mercaptopropyl-trimethoxysilane to synthesize cost-effective nanomaterials endowed with the capacity for selective adsorption of As(Ⅲ) through copolymerization and atmospheric pressure drying. The synthesized materials were systematically characterized using X-ray diffraction, scanning electron microscopy, and C/H/N/S elemental analysis, revealing a specific surface area of 472.39 m 2 /g, a particle size of 12.7 nm, and a loading capacity of 3.115 mmol/g. The DGT combined with gel prepared from this material has a specific affinity for As(III) without adsorbing As(V).Its adsorption efficiency for As(III) may reach 84.5% within the first hour. This DGT technique has a linear detection range of 0.5–15 mg/L (R 2 = 0.99995), an elution recovery of 85.1%–102.7% (RSD < 10%, n = 3), and a maximum adsorption capacity of 301.7 μg/cm 2 , meeting requirements for long-term environmental monitoring. The experiment studied the effects of interfering factors, including pH values ranging from 3–9, ionic strength of 10–500 mmol/L NaNO₃, Fe 2 ⁺ 0–5.0 mg/L, Mn 2 ⁺ 0–1.0 mg/L, As(V) 0–5.0 mg/L, dissolved organic carbon 0–20.0 mg/L, SO₄ 2 ⁻ 0.55–1.10 g/L, and PO₄ 3 ⁻ 5.0–10.0 mg/L. The device maintained a stable treatment performance under all these conditions. When the DGT device was deployed in spiked river water, estuarine water, and seawater, a comparison of its adsorption performance with existing methods showed that the device had a comparable adsorption performance and demonstrated excellent long-term stability in practical water environment applications.
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ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2019
·
IF 7.149
Zhou Fang,Kexin Li,Yuan Li,Hao Zhang,Kevin C. Jones,Xinyu Liu,Shengyu Liu,Lena Q. Ma,Jun Luo
Psychiatric pharmaceuticals are widely distributed in the aquatic environment and have attracted recent attention due to their potential for environmental effects. A robust and reliable in situ passive sampling approach, the diffusive gradients in thin-films (DGT) technique, is developed here to measure 14 psychiatric pharmaceuticals. A new binding material, mixed-mode cation exchange resin (Poly-Sery MCX, 40 μm, CNW, Germany), was used for the first time in DGT and compared to XAD and HLB. Reliable elution efficiencies of the pharmaceuticals from the binding gels were obtained in methanol/ammonia, and diffusion coefficients for all the compounds were determined. The influence of diffusive layer thickness (0.515–2.015 mm), deployment time (3–168 h), and important environmental conditions—pH (3.02–9.45), ionic strength (0.0001–0.5 M), and dissolved organic matter (0–20 mg L–1)—were evaluated. The capacity of XAD, HLB, and MCX gels for binding all the test pharmaceuticals was ∼335 μg per disc, meaning that DGT could theoretically be deployed for over 30 months if there are no competitive effects or confounding factors. The uptake kinetics of psychiatric pharmaceuticals onto MCX gel were much faster than those onto XAD and HLB gels in the first hour. DGT measured concentrations of test pharmaceuticals at two sample points in a river (over 6 days) were comparable to those obtained by grab sampling. This study demonstrates the accuracy and reliability of DGT for measuring psychiatric pharmaceuticals across a wide range of freshwater conditions found in the natural environment.
研究领域:
环境科学
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药学
·
分析化学
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PubMed
高影响因子
JOURNAL OF SOILS AND SEDIMENTS
·
2021
·Vol. 21
·期 6
·2287-2300
·
IF 3.308
Kang Longfei,Zhang Guoqiao,Chu Guixin
Purpose Phosphorus (P) fertilization methods significantly affect soil P availability, transformation, and crops yield. However, contradictory or paradoxical results are often available, and debates about this issue have never ceased so far. Therefore, the aims of this study are to explore influences of different P application methods on availability and transformation of added P in drip-irrigated system, and the responses of maize P uptake and its agronomic performances to P fertigation are also investigated. Materials and methods Here, we conducted a pot and filed experiments in drip-irrigated calcareous soil. Treatments included different P sources (phosphoric acid; polyphosphoric acid) with basal and split repeated application manners. Results and discussion Compared to the basal application, the average values of C DGT -P (P concentrations tested via diffusive gradient in thin films technique), Olsen-P, water-soluble P, and in situ P in the split repeated P application increased by 23.7%, 10.2%, 16.5%, and 34.4%, respectively (pot experiment). Furthermore, the average values of labile P (resin P and NaHCO 3 -P) and moderately labile P (NaOH-P) with the repeated P addition increased by 19.7% and 12.6%, whereas the concentrations of non-labile P lowered by 19.3%, respectively, relative to basal application treatment (pot experiment). The same trend was obtained in field experiment, implying that complete repeated P addition significantly increased P availability, reduced soil P transformation, and decreased P fixation. Therefore, a better agronomic performance of maize (P uptake, grain yield, and phosphorus use efficiency) was achieved in the complete repeated P application rather than basal application. Besides, diffusive gradient in thin film technique (DGT) was proved to be an accurate and powerful approach in testing soil available P. Conclusions Our findings elucidate that repeated delivering P through fertigation method can be recommended as an effective P application strategy in drip-irrigated field, especially in semi-arid and arid regions. The feasibility of DGT method was certified and C DGT -P could well characterize plant-accessible P.
研究领域:
农业
·
土壤学
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植物营养
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环境科学
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高影响因子
MICROCHIMICA ACTA
·
2015
·Vol. 182
·期 15
·2419-2425
·
IF 3.741
Feng Zhongmin,Guo Tingting,Jiang Zhiwen,Sun Ting
We have investigated the possibility of sampling ammonium ion using the diffusive-gradients-in-thin-films technique (DGT) by introducing a novel binding agent that is based on micro-sized zeolite. The performance of zeolite-DGT was characterized by measurement of the following parameters: (1) the diffusion coefficient of ammonium ion in hydrogel; (2) the adsorption rate of ammonium ion by the zeolite binding gel; (3) the elution efficiency, and (4) the effects of pH, ionic strength and interfering ions on DGT. The method was validated by studying the uptake of ammonium ion from in freshwaters by zeolite gels which was found to be fast enough to meet the requirements of DGT. The concentrations determined via DGT agreed well with the concentrations determined in bulk solutions. Sampling of ammonium ion using zeolite-DGT was consistent over the pH 3 to 8 range and the 0.001 to 10 mM ionic strength range. The method also performs predictably in natural waters containing various metal ions. The technique is considered to be a viable passive tool for sampling ammonium from aqueous solutions.
Schematic representation of the principle of DGT and the determination of mass accumulated on the binding gel.
研究领域:
环境科学
·
分析化学
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高影响因子
Analytical Methods
·
2025
·
IF 2.6
Zhaoyang Gu,Yongming Huang,Beichen Lin,Kunde Lin
Current methods for determining dissolved reactive phosphorus (DRP) in sediment porewater mainly rely on ex-situ analysis, which can be labor-intensive and introduces errors due to changes in the concentration and morphology during sampling and transportation. Therefore, there is a clear need for in-situ measurement methods for DRP in sediment porewater. In this study, a novel in-situ analytical method was developed by combining diffusive gradients in thin-films (DGT) and digital imaging techniques, based on the classic phosphomolybdenum blue (PMB) method. During deployment, DRP in sediment porewater diffuses into the DGT device, while reducing reagent (ascorbic acid) from the diffusive gel simultaneously diffuses into the binding gel and reacts with ammonium molybdate, resulting in the formation of PMB compounds. The color of the PMB compounds was recorded in-situ using a digital imaging technique, and the resulting images were analyzed to calculate the concentration of DRP in surface sediment porewater. By using the new method, analytical data of DRP in surface sediment porewater could be quickly obtained in the field near real-time, without water sampling and any further sample treatment, transportation and instrumental analysis in laboratories. The key parameters including the loading procedure for colorimetric reagents in the gels, the concentrations of ammonium molybdate and ascorbic acid, the amount of C18, and the thickness of the C18 binding gel, were systematically optimized. The optimized method demonstrated a wide linear range (4 ‒ 1000 μmol L-1, R2=0.993), with satisfactory accuracy (-6.23% ‒ 8.68%, n = 3) and good precision (6.60% ‒ 13.46%, n = 3) at an exposure time of 60 min. The method also performed well across different salinities (0 ‒ 35) and in the presence of interfering ions (SiO32‒, AsO33‒, F‒, and S2‒). The method was successfully applied to both freshwater and seawater sediments, with results comparable to those obtained using traditional analytical methods. Overall, the proposed method provides a new strategy for in-situ determination of DRP in surface sediment porewater.
研究领域:
环境分析化学
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海洋与淡水沉积物分析
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原位传感技术
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比色检测
·
地球化学
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PubMed
高影响因子
危险品化学品经营许可证（带存储）