MICROCHEMICAL JOURNAL
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2023
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IF 4.8
Yang Li,Xiaohuan Zang,Yahuan Li,Shuaihua Zhang,Chun Wang,Zhi Wang
A defective UiO-66 with rich defect sites was synthesized by a modulator-induced defect formation approach and used as the solid-phase microextraction (SPME) fiber coating material. The extraction experimental results showed that the defective UiO-66 coating can selectively extract the fungicides chlorothalonil, vinclozolin, dimethachlon, procymidone and iprodione with a high adsorption capability. The superior adsorption capability can be attributed to hydrophobic, Lewis acid-base and hydrogen bonding interactions. After optimization, a SPME with the defective UiO-66 as the fiber coating combined with GC–MS detection was established for the sensitive and selective determination of the five fungicides in fruit samples. Under the optimized experimental conditions, the quantitative linear response was in the range of 0.83–300 ng g −1 , with the coefficients of determination in the range from 0.9970 to 0.9986 and the limits of detection between 0.25 and 9.0 ng g −1 for the analytes. The method was successfully applied for the determination of the fungicides in different fruit samples. Satisfactory method recoveries (82.7%-117.7%) and good precisions with the relative standard deviations being from 3.2% to 12% were achieved.
研究领域:
分析化学
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环境科学
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食品科学
✓ 已验证
产品关联
DOI
高影响因子
Analytical Methods
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2019
·Vol. 11
·期 42
·5421-5430
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IF 2.378
Yaliang Wang,Li Xu,Hui Zhu,Junguo Dong,Ping Cheng,Zhen Zhou
The unique ionization characteristics of plasma can be used in multimodal ion sources, which have expanded plasma-based ambient ionization mass spectrometry rapidly to accommodate a range of analytical applications. In this work, microwave plasma torch (MPT) and low-temperature plasma (LTP) ion sources coupled with an atmospheric-pressure interface linear ion trap time-of-flight spectrometry (LIT-TOFMS) instrument, respectively, were developed. Instead of desorption sampling, spray-inlet sampling was used for MPT- and LTP-LIT-TOFMS instruments, respectively, to analyze agrochemicals, and the results were compared to those obtained from traditional ESI-TOFMS. For the methanol solutions of eight reference samples (atrazine, chlorpyrifos, dimethoate, diphenylamine, imazalil, imidacloprid, isoprocorb, and triazophos), spray-inlet MPT and LTP exhibited similar high sensitivity with limits of detection at parts-per-billion, which was comparable to or higher than that exhibited by ESI. However, the spectra obtained from ambient mass spectrometric analysis of the pesticide residues in apple and grape peel extracts using MPT and LTP were comparable, and showed much higher ion measurements than those from the ESI spectra. In order to verify the stability of this method, eight agrochemicals were added to the apple peel extract at concentrations of 0.1 ng mL−1 for atrazine, diphenylamine, imazalil, isoprocorb, and triazophos, and 1 ng mL−1 for chlorpyrifos, dimethoate, and imidacloprid. The determined recovery rates for MPT-, LTP-, and ESI-LITMS are 61.7–83.3%, 60.0–97.5%, and 19.3–61.9%, respectively, probably due to ionization suppression caused by the matrix effect. This study shows that spray-inlet coupled MPT- and LTP-LIT-TOFMS can be effectively used for direct and rapid identification of various compounds with high sensitivity and high reproducibility in a very complex matrix, and are more suited for food quality control for contamination, fraud or authenticity checks, and even environmental quality assessment for pollutant screening, etc.
研究领域:
分析化学
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食品科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Surfaces and Interfaces
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2021
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IF 4.837
Xiao-Ting Zhen,Ya-Ling Yu,Min-Zhen Shi,Si-Chen Zhu,Tian-Ci Yan,Zi-Xuan Yue,Yu-Xin Gu,Hui Zheng,Jun Cao
The Hawthorn kernel activated carbon (HKAC), acquired from food waste (hawthorn kernel) by a two-step method including carbonization operation and thermally activating potassium hydroxide process, was prepared. Morphological integrity and crystalline state of the HKAC were characterized by scanning electron microscopye and X-ray diffraction. Structural feature of the HKAC was investigated by the Brunauer–Emmett–Teller method, Fourier transform infrared spectroscopy , Raman spectroscopy together with zeta potential . The HKAC contained a specific surface area of 1269.92 m 2 /g and pore volume of 0.67 cm 3 /g. The optimized adsorption conditions were to use HKAC with a carbonization temperature of 550 °C were at a concentration of 0.6 g/L for adsorption in a solution with a temperature of 60 °C and a pH of 6.0. The kinetic studies proved that the pseudo-second-order model fitted experimental data best with the high correlation coefficient values of 0.9968–0.9993. Besides, experimental results revealed that Langmuir isotherm model gave the best fit among the studied isotherm models with a maximum adsorption capacity of 100.00 mg/g, the experimental results revealed that the Langmuir isotherm model was more consistent than the Freundlich isotherm model with a maximum adsorption capacity of 100.00 mg/g, and the adsorption of fungicides onto HKAC was endothermic spontaneous process. Moreover, it was confirmed in tap water and Dendrobium that the removal rate of the six fungicides remained at 86.3% to 96.2% after five cycles of HKAC even in a complex matrix. The aforesaid satisfying experimental results proved that HKAC was a cost-effective and green adsorbent for removing water and plant contaminated by fungicides.
研究领域:
环境科学
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农业科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF FOOD PROTECTION
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2022
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IF 2.745
Jia Zhang,Wei Jiang,Zhihang Jia,Wenjie Zhang,Ting Zhang,Meng Wei
Imazalil is a chiral fungicide widely used to protect strawberries against gray mold, which may pose threats to food safety. This study aims to investigate the stereoselective behavior of imazalil during strawberry growth and strawberry wine production. A method was proposed and validated for the extraction and quantitative analysis of imazalil residues in strawberry, strawberry pomace, and strawberry wine by using ultra-high performance liquid chromatography-tandem mass spectrometry. The method exhibited mean recoveries ranging from 86.2% to 119.7% with relative standard deviations of 0.1–11.3%. The dissipation curve of imazalil during strawberry growth followed the first-order kinetic model with a half-life ranging from 6.5 to 7.1 days. Significant enantioselectivity of imazalil was observed in strawberry grown under field conditions and strawberry wine production process, with enantiomeric fraction values ranging from 0.51 (2 h) to 0.42 (27d) and from 0.48 (0d) to 0.52 (10d), respectively. (+)-imazalil was preferentially degraded in strawberry under field conditions, while (−)-imazalil was preferentially degraded during the fermentation process. The processing factor was lower than 1 for each procedure, indicating that the wine-making process can reduce imazalil residue in strawberry. These findings may facilitate a more accurate risk assessment of imazalil and provide important guidance for the safe and efficacious use of imazalil in agriculture.
研究领域:
食品科学
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农业化学
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产品关联
DOI
PubMed
高影响因子
ANALYTICA CHIMICA ACTA
·
2023
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IF 6.2
Siyu Wei,Xinfang Wang,Xinyu Zhao,Ke Zhao,Linzhe Xu,Yingbo Chen
Background Excessive pesticide residues will seriously endanger human health. The complexity and lag of the current popular analytical methods hinder the timeliness of food safety analysis. Surface-enhanced Raman scattering (SERS) was an ultra-sensitive vibration spectroscopy technology with the advantages of less time cost, non-destructive and semi-quantitative detection, which has attracted much attention in the rapid field detection of pesticide residue. It was clear that we need an efficient and convenient substrate for pesticide residue detection based on SRES technology, which needs to be portable, flexible, transparent and easy to detect irregular object surfaces. Results A novel SERS sensor was designed to detect single and multi-component pesticide residues on irregular fruit and vegetable surfaces by in-situ growth of silver nanoparticles on a flexible and transparent fluorinated polyimide (FPI) substrate. Among them, Ag NPs were synthesized by liquid phase reduction method (AgNO 3 -PVP and NaBH 4 ). The results showed that the detection limit of 1–4 BDT was down to 10 −10 mol L −1 , the enhancement factor (EF) was up to 1.57 × 10 7 , and relative standard deviation (RSD) was 7.49 %. By this method, tricyclazole solution at a concentration of 0.01 mg L −1 was still detectable by the FPI@Ag SERS substrate. The linear quantification was achieved in the range from 100 mg L −1 to 0.01 mg L −1 . Two mixed pesticides, tricyclazole and imazalil, were also successfully distinguished. Significance This represents the formation of a flexible, foldable and transparent substrate for rapid on-site detection. Results can be obtained in <5 min by attaching the substrate to the substance to be tested. And the SERS substrate prepared with high sensitivity, stability, portable and convenient analysis, which provided new ideas for efficient and rapid household food safety detection.
研究领域:
食品安全检测
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分析化学
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产品关联
DOI
PubMed
高影响因子
Journal of Analytical Methods in Chemistry
·
2023
·
IF 2.6
Xiaoyu Yang
Simultaneous enantioseparation of three commonly used chiral antifungal pesticides (diniconazole, hexaconazole, and imazalil) was first studied based on micellar electrokinetic chromatography (MEKC) with hydroxypropyl-γ-CD (HP-γ-CD) as chiral selector. In this study, the importance of experimental parameters such as chiral selector type and concentration, sodium dodecyl sulfate (SDS) concentration, the ratio of methanol, and separation voltage in optimizing were investigated. The simultaneous enantioseparation of diniconazole, hexaconazole, and imazalil was successfully achieved in 30 mM borate buffer (pH 9.0) containing 10 mM HP-γ-CD and 20 mM SDS with methanol (8%) added as organic modifiers. The resolution of diniconazole, hexaconazole, and imazalil was 15.2, 2.12, and 2.78, respectively, and the peak efficiency (N) was over 566,825 plates/m. This study provides an alternative way to systematically separate chiral antifungal pesticides with high efficiency.
研究领域:
分析化学
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农药科学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）