JOURNAL OF CHROMATOGRAPHY A
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2019
·
IF 3.858
Wei-Qi Xie,Yi-Xian Gong,Kong-Xian Yu
A fast, convenient and commercially available approach for analyzing humic acid content in fertilizer using headspace gas chromatography (HS-GC) is presented in this paper. Humic acid is converted into carbon dioxide based on the oxidation of humic acid in strong acidic medium and can be measured via automatic HS-GC. Conditions for the alkaline extraction and the humic acid oxidation process are also optimized. The new technique proved to be precise (RSD ≤ 3.59%) and accurate (relative errors≤9.46% as compared with the spectrophotometric approach). The newly established technique presents a practical tool to routinely analyze humic acid content in fertilizer during the fertilizer production.
研究领域:
分析化学
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农业科学
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DOI
高影响因子
POLYMER TESTING
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2019
·
IF 2.943
Ning Yan,Xiao-Fang Wan,Xin-Sheng Chai
This paper reports on a novel method for rapid determination of the degree of deacetylation (DD) of chitosan samples by headspace gas chromatography (HS-GC). In this method, overdose of an acid is added to protonate the free amino groups in chitosan, which further reacts with bicarbonate (as an alkali titrant) in a close vial. Based on measuring the HS-GC signal for CO 2 vs. the volume of HCO 3 − added by a stepwise titration, two transition points can be obtained. The DD value is calculated by net volume of HCO 3 − consumed, i.e., by the R NH 3 + groups in chitosan. The results showed that the present method has a good measurement precision (RSD < 0.82%) and accuracy (relative differences < 6.46% when compared with the results measured by a reference method). Since the HS-GC can perform an automated sample reaction equilibration and measurement, it could be much more efficient than the existing methods in the batch sample analysis.
研究领域:
分析化学
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生物材料学
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产品关联
DOI
高影响因子
Foods
·
2020
·Vol. 9
·期 4
·505
·
IF 4.092
Qi Zhou,Guijie Li,Zhu Ou-Yang,Xin Yi,Linhua Huang,Hua Wang
An efficient and practical method for identifying mandarin juice over-blended into not from concentrate (NFC) orange juice was established. Juices were extracted from different cultivars of sweet orange and mandarin fruits. After being pasteurized, the volatile organic compounds (VOCs) in the juice samples were extracted using headspace solid-phase microextraction, and qualitatively and quantitatively analyzed using gas chromatography–mass spectrometry detection. Thirty-two VOCs contained in both the sweet orange juice and mandarin juice were used as variables, and the identification model for discriminating between the two varieties of juice was established by principal component analysis. Validation was applied by using common mandarin juices from Ponkan, Satsuma and Nanfengmiju cultivars blended at series of proportions into orange juices from Long-leaf, Olinda, and Hamlin cultivars. The model can visually identify a blending of mandarin juice at the volume fraction of 10% or above.Keywords:mandarin juice;not from concentrate (NFC);principal component analysis (PCA);headspace solid-phase microextraction (HS-SPME)
研究领域:
食品科学
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分析化学
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农业化学
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产品关联
DOI
PubMed
高影响因子
MOLECULES
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2022
·Vol. 27
·期 14
·4393
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IF 4.927
Chao Li,Huiying Wan,Xinlong Wu,Jiaxin Yin,Limin Zhu,Hanjiang Chen,Xinbo Song,Lifeng Han,Wenzhi Yang,Heshui Yu,Zheng Li
Volatile organic compounds (VOCs) are the main chemical components ofSchizonepetae Spica(SS), which have positive effects on the quality evaluation of SS. In this study, HS-SPME-GC-MS (headspace solid-phase microextraction-gas chromatography-mass spectrometry) and HS-GC-IMS (headspace-gas chromatography-ion mobility spectrometry) were performed to characterize the VOCs of SS from six different regions. A total of 82 VOCs were identified. In addition, this work compared the suitability of two instruments to distinguish SS from different habitats. The regional classification using orthogonal partial least squares discriminant analysis (OPLS-DA) shows that the HS-GC-IMS method can classify samples better than the HS-SPME-GC-MS. This study provided a reference method for identification of the SS from different origins.Keywords:volatile organic compounds;Schizonepetae Spica;HS-SPME-GC-MS;HS-GC-IMS;OPLS-DA
研究领域:
药学化学
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分析化学
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中药学
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产品关联
DOI
PubMed
高影响因子
FOOD SCIENCE AND BIOTECHNOLOGY
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2019
·Vol. 28
·期 5
·1349-1358
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IF 0.888
Lin Jie,Shi Yuanxu,Dong Chunwang,Wang Xiaochang
The perceived aroma of oolong tea is primarily and directly affected by its infusion matrix, and the release persistence of headspace volatiles can better illustrate the persistent aroma. Headspace solid phase microextraction coupled with gas chromatography–mass spectrometry was performed to analyze the headspace constituents of oolong tea. The presence of the infusion matrix seemed to prevent the headspace release of certain odorants. The release of indole, nerolidol, and α -farnesene was also remarkably enhanced or depressed (2.70, 1.56, and 0.69-fold in tea infusion versus in dry leaves). Moreover, the amount of volatile species gradually decreased with increased water ratio. Eight odorants were determined to be stable and persistent during continuous infusion, whereas six were determined to be less persistent (gradually decreased or stopped releasing). The volatile dilution test further confirmed the persistent release of nerolidol.
研究领域:
食品科学
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植物化学
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DOI
PubMed
高影响因子
ELECTROPHORESIS
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2018
·Vol. 39
·期 14
·1771-1776
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IF 2.569
Mei-E Yue,Qiaoyan Lin,Jie Xu,Ting-Fu Jiang
An ionic liquid-based headspace in-tube liquid-phase microextraction (IL-HS-ITLPME) in-line coupled with CE is proposed. The method is capable of quantifying trace amounts of phenols in environmental water samples. In the newly developed method, simply by placing a capillary injected with ionic liquids (IL) in the HS above the aqueous sample, volatile phenols were extracted into the IL acceptor phase in the capillary. After extraction, electrophoresis of the phenols in the capillary was carried out. Extraction parameters such as the extraction time, extraction temperature, ionic strength, volume of the sample solution, and IL types were systematically investigated. Under the optimized conditions, enrichment factors for four phenols were from 1510 to 1985. The proposed method provided a good linearity, low limits of detection (below 5.0 ng/mL), and good repeatability of the extractions (RSDs below 6.7%, n = 6). This method was then utilized to analyze two real environmental samples of Xiaoxi Lake and tap water, obtaining acceptable recoveries and precisions. Compared with the usual HS-ITLPME for CE, IL-HS-ITLPME-CE is a simple, low cost, fast, and environmentally friendly preconcentration technique.
研究领域:
分析化学
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环境科学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF FOOD COMPOSITION AND ANALYSIS
·
2025
·
IF 4.6
Tongtong Yang,Bo Tang,Junyi Tang,Chenqi Xu,Yanlong Hong,Fei Wu,Xiao Lin
Pheretima products are widely used, but the stenchy odor is a constraint to their application. In this study, 86 and 673 volatile components (VOCs) were identified in Pheretima and its extracts using headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS) and headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS), respectively. An increase in acid and amine contents after processing was found, which may explain the increased stenchy odor. Through orthogonal partial least squares discriminant analysis (OPLS-DA), 14 differential markers between aqueous and alcoholic extracts were screened, and 3-methylbutanal, pentanal, and trimethylamine were identified as the key differential odor components. Combined with relative odor activity value (ROAV) analysis, 10 key odor components were identified, including: 3-methylbutanal, 1-octen-3-ol, dimethyl trisulfide, (2 E ,6 Z )-nona-2,6-dienal, methyl mercaptan, guaiacol, isobutyraldehyde, 1,8-cineole, 2-pentylfuran, and pentanal. This study provides theoretical support for the optimization of the odor of Pheretima-containing products and promotes their application.
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产品关联
DOI
高影响因子
SN Applied Sciences
·
2021
·Vol. 3
·期 3
·1-9
·
IF 0
Ma Yinzheng,Wen Yingying,Chen Jinping,Zhang Yunxia,Zhang Haiying,Sui Jinlei,Yi Guohui,He Xiaowen
A rapid and sensitive headspace gas chromatography-mass spectrometry (HS-GC–MS) method was established for the determination of benzyl isothiocyanate (BITC) in the peel, pulp, and seeds of Carica papaya Linn. Tween 80 solution with a concentration of 0.002% ( w/v ) was chosen as a headspace medium for solving the poor solubility of BITC in water without using organic solvents and ensuring high headspace efficiencies. Extraction parameters had been evaluated and optimized by using an orthogonal design with an OA 9 (3 4 ) table. Optimal headspace conditions were obtained when vials were equilibrated at 80 °C for 20 min at a stirring speed of 375 rpm. The calibration curve obtained by using GC–MS was linear in a concentration range of 10–320 ng/mL. The recoveries of peel, pulp, and seeds ranged from 97.3 to 100.6% with RSDs less than 3.0%. The method is simple, rapid, sensitive, and environmentally friendly. It is suitable for analyzing BITC in papaya fruit and is expected to have important application potential in the extraction of water-insoluble volatile components in foods, plants, medicines, and other samples.
研究领域:
食品科学
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分析化学
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植物学
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产品关联
DOI
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2019
·
IF 3.571
Ning Yan,Xiao-Fang Wan,Xin-Sheng Chai
This study reported a new headspace gas chromatography (HS-GC) for simultaneously determining the degree of deacetylation (DD) and the degree of substitution (DS) in carboxymethyl chitosan (CMCS), which were based on HS-GC measuring the amounts of CO2 released from both the bicarbonate decomposition suppressed by -NH2 and the reaction between the bicarbonate and the acidified carboxymethyl and amino groups in CMCS. The results showed that the present method has a good measurement precision (RSD < 2.55%) and accuracy (relative differences <5.90%). Compared with the current titration-based method, the present HS-GC techniques provide a more reliable testing in the quantification of amino and carboxymethyl contents in CMCS. Moreover, since the HS-GC can perform an automated sample reaction equilibration and measurement, it could be much more efficient than the existing methods in the batch sample analysis.
研究领域:
分析化学
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生物材料学
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DOI
高影响因子
JOURNAL OF AOAC INTERNATIONAL
·
2020
·Vol. 104
·期 3
·712-718
·
IF 1.51
Wei Min,Zheng Feng,Song Xuyan,Li Ran,Pan Xi,Guo Guoning,Yu Qiongwei,Feng Yuqi
BackgroundSome volatile compounds in mouthpiece cigarette adhesive emit irritating odors and affect the taste of smoking cigarettes. Therefore, it is necessary to monitor the volatile compounds in mouthpiece cigarette adhesive.ObjectivesA rapid and simple analytical method of volatile compounds in mouthpiece cigarette adhesive was established.MethodsIn this study, headspace (HS) injection coupled with GC–MS was utilized for qualitative and quantitative analysis. Initially, the volatile compounds in mouthpiece cigarette adhesives were detected by HS-GC–MS, followed by spectrum library retrieval. The detected compounds with the similarity to a spectrum library of more than 85% were further identified by comparing the retention time and mass spectra of the detected volatile compounds and those of the corresponding standard samples. The quantitative analysis of nine identified volatile compounds was performed.ResultsEleven volatile compounds in the mouthpiece cigarette adhesive were accurately identified. The quantitative analytical method of nine volatile compounds in mouthpiece cigarette adhesive was validated to have good linearities (R2 > 0.9932) within the range of 20–5000 ng/g. The detection limits of 9 compounds were within the range of 3.1–147.7 ng/g. The intra- and inter-day relative standard deviations were less than 19.8%. The recoveries of these 9 compounds spiked into mouthpiece cigarette adhesive were 68.1–108.3%.ConclusionsThe proposed method is rapid, simple, and accurate for qualitative and quantitative analysis of volatile compounds in the mouthpiece cigarette adhesive.HighlightsThe developed analytical method is expected to be used to monitor volatile compounds in various adhesives.
研究领域:
分析化学
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烟草科学
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产品关联
DOI
PubMed
高影响因子
Analytical Methods
·
2014
·Vol. 6
·期 9
·2965-2972
·
IF 1.938
Qi Wang,Yun-Fei Xie,Wei-Jun Zhao,Peng Li,He Qian,Xiao-Zhi Wang
A fast and quantitative method for the detection of biogenic amines based on the microchip-based high-field asymmetric waveform ion mobility spectrometry (FAIMS) technique was established for evaluating the degree of spoilage of pork stored at room temperature. Trimethylamine (TMA) was selected as a good indicator for its volatility and high proton affinity. Analysis of standard TMA showed the same characteristic peak with the pork sample. The limit of detection of the system for TMA dissolved in deionized water, with 100 μL of 8 mol L−1 NaOH, was 3 ng and the measurement was accomplished within 15 s. The relative standard deviation (RSD) was 6.20%. The delivery of the sample gas was based on the dynamic headspace method. The effect of the storage time on the formation of biogenic amines was examined, and not surprisingly, the content of TMA increases over time. The total volatile basic nitrogen (TVB-N) was measured simultaneously based on the classical semi-micro Kjeldahl method. A good correlation coefficient between these two methods was obtained, the correlation coefficient was 0.952. Therefore the microchip-based FAIMS technique provides a quantitative classification of the spoilage or freshness of pork, especially when a rapid detection is needed.
研究领域:
食品科学
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分析化学
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产品关联
DOI
高影响因子
Food Chemistry-X
·
2025
·
IF 8.2
Tianyu Wang,Hang Lu,Yuanyong Tian,Hui Zhao,Xuefeng Lu,Zhaoxia Wu,Shiwei Niu
Ammonia accumulation in aquaculture systems affects the sensory quality of Eriocheir sinensis , and mechanisms linking ammonia to aroma changes remain unclear. This study investigated how ammonia exposure in aquatic environments (0, 10.47, and 41.87 mg/L total ammonia-N, 48 h) alters aroma profiles of E. sinensis meat. Using HS-SPME-GC–MS and HS-GC-IMS, we identified 26 key volatile organic compounds (VOCs) defining aroma differences. Concurrently, fatty acid profiles were analyzed through GC–MS. Ammonia exposure reduced fishy (trimethylamine, 1-octen-3-ol) and meaty (methional) aromas while enhancing plant-like (phenylethyl alcohol) and nutty (2-methylbutanal) aromas in the low-concentration group; high-concentration ammonia diminished hexanal and sulfur-containing compounds, aligning with aroma evaluation trends. Further, n-3 polyunsaturated fatty acids increased after ammonia exposure, correlating with VOCs derived from lipid metabolism. These findings reveal ammonia-induced metabolic changes in flavor precursors (e.g., fatty acids) and flavor compounds (e.g., VOCs) and provide feasible insights for optimizing aquaculture practices to improve crab quality.
研究领域:
水产养殖
·
食品科学
·
分析化学
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环境毒理学
·
风味化学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）