JOURNAL OF CHROMATOGRAPHY A
·
2014
·
IF 4.258
Sheng-Ming Xie,Mei Zhang,Zhi-Xin Fei,Li-Ming Yuan
Chiral metal-organic frameworks (MOFs) are a new class of multifunctional material, which possess diverse structures and unusual properties such as high surface area, uniform and permanent cavities, as well as good chemical and thermal stability. Their chiral functionality makes them attractive as novel enantioselective adsorbents and stationary phases in separation science. In this paper, the experimental comparison of a chiral MOF [In 3 O(obb) 3 (HCO 2 )(H 2 O)] solvent used as a stationary phase was investigated in gas chromatography (GC), high-performance liquid chromatography (HPLC) and capillary electrochromatography (CEC). The potential relationship between the structure and components of chiral MOFs with their chiral recognition ability and selectivity are presented.
研究领域:
分析化学
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材料科学
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PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2015
·
IF 4.169
Jian-Jun Zhong,Ningbo Liao,Tian Ding,Xingqian Ye,Dong-Hong Liu
Direct separation of biogenic amines by reversed-phase liquid chromatography (RPLC) is not an easy task because their basic and hydrophilic characteristics can lead to poor retention, column overloading, peak tailing, and hence low efficiency. Rather than routinely resorting to derivatization or using classical hydrophobic ion-pair reagents (IPR), this work proposes a new RPLC method making use of the chaotropic salt KPF 6 as inorganic additive to an acidic acetonitrilic eluent to remedy the difficulties. Amine retention, overload behavior, peak shape, and column efficiency were significantly improved. The use of excess KPF 6 led to a very slight decrease of amine retention. Depending on amine, the dependence of the logarithmic retention factor on the volume percent of acetonitrile could be reasonably linear or quite convex. Coupled with UV detection, the method was applied to trace analysis for six biogenic, aromatic or heterocyclic amines in three types of food after a sample cleanup, as necessary, by ion-pair extraction. The reliability of the whole analysis was demonstrated to be satisfactory. The proposed method outperforms existing methods in that it eliminates the need for long and cumbersome derivatization procedures without losing sensitivity; it also represents a good surrogate for classical ion-pair chromatography (IPC) because of the desirable hydrophilicity of chaotropic salts.
研究领域:
食品科学
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分析化学
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PubMed
高影响因子
Food Science & Nutrition
·
2019
·Vol. 7
·期 6
·2151-2158
·
IF 1.747
Kai Yang,Cheng Zhou,Zhenhuan Yang,Lan Yu,Ming Cai,Changqing Wu,Peilong Sun
Although sulfites are widely used in shrimp processing, the contents of residual sulfite need to be strictly controlled due to their potential toxicity. In this paper, a novel method was developed for determination of the free and total sulfites in shrimps. Major procedures of the method includes separation of free and total sulfites with ultrasound-assisted extraction and pH adjustment for 20 min, then a precolumn derivatization was conducted by 2,2′-Dithiobis (5-nitropyridine) and verified by LC-MS, and finally HPLC coupled with an ultraviolet (UV) detector was carried out. Results indicated that the UV absorption wavelength shifted from 213 (sulfites) to 320 nm (new disulfide compounds), significantly reducing the interference of natural occurring compounds and solvents in the matrix. The standard curves exhibited a good linear range of 3.2–51.2 mg/L ( R 2 = 0.9996). The limit of detection (LOD) and limit of quantification (LOQ) were 0.3 and 1.0 mg/L, respectively. The contents of free and total sulfite in frozen shrimps were 26.58 ± 0.48 and 31.44 ± 0.83 mg/kg calculated by SO 2 , respectively. These were similar ( p > 0.05) to the data obtained by the method of ion chromatography. In conclusion, the new developed method has been proved to be a reliable and economic method for effective determination of free and total sulfites in the shrimps, and the method could be expanded in determination of the sulfites in other food products.
研究领域:
食品科学
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分析化学
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DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2023
·
IF 13.6
Huimei Pan,Boqiang Li,Jie Yang,Wenzhe Liu,Wang Luo,Baiyang Chen
This study revisited a list of inorganic iodine species on their detections and conversions under different water conditions. Several surprising results were found, e.g., UV–vis spectrophotometry is the only reliable method for I 3 – and I 2 determinations with coexisting I – /IO 3 – /IO 4 – , while alkaline eluent of IC and LC columns can convert them into I – completely; IO 4 – can be converted into IO 3 – completely in IC columns and partly in LC columns; a small portion of IO 3 – was reduced to I – in LC columns. To avoid errors, a method for detecting multiple coexisting iodine species is suggested as follows: firstly, detecting I 3 – and I 2 via UV–vis spectrophotometry; then, analyzing IO 4 – (> 0.2 mg/L) through LC; and lastly, obtaining I – and IO 3 – concentrations by deducting I − and IO 3 – measured by IC from the signals derived from I 3 – /I 2 /IO 4 – . As for stability, I − or IO 3 – alone is stable, but mixing them up generates I 2 or H 2 OI + under acidic conditions. Although IO 4 – is stable within pH 4.0–8.0, it becomes H 5 IO 6 /H 3 IO 6 2 – in strongly acidic/alkaline solutions. Increasing pH accelerates the conversions of I 3 – and I 2 into I – under basic conditions, whereas dissolved oxygen and dosage exert little effect. Additionally, spiking ICl into water produces I 2 and IO 3 – rather than HIO.
研究领域:
分析化学
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环境科学
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水处理工程
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DOI
PubMed
高影响因子
Current Pharmaceutical Analysis
·
2021
·Vol. 17
·期 7
·873-884
·
IF 0.89
Xia Yun-Yan,Zou Qiao-Gen,Yang Yu-Fei,Sun Qian,Han Cheng-Qun
Background: High-Performance Liquid Chromatography (HPLC) method has been used to detect related impurities of perampanel. However, the detection of impurities is incomplete, and the limits of quantification and detection are high. A sensitive, reliable method is badly needed to be
developed and applied for impurity detection of perampanel bulk drug. Objective: Methodologies utilising HPLC and Gas Chromatography (GC) were established and validated for quantitative determination of perampanel and its related impurities (a total of 10 impurities including 2 genotoxic
impurities). Methods: The separation was achieved on a Dikma Diamonsil C18 column (250 mm 4.6 mm, 5 μm) with the mobile phase of 0.01 mol/L potassium dihydrogen phosphate solution (A) and acetonitrile (B) in gradient elution mode. The compound 2-bromopropane was determined on an Agilent
DB-624 column (0.32 mm 30 m, 1.8 μm) by electron capture detector (μ-ECD) with split injection ratio of 1:5 and proper gradient temperature program. Results: Both HPLC and GC methods were established and validated to be sensitive, accurate and robust according to the International
Council for Harmonization (ICH) guidelines. The methods developed were linear in the selected concentration range (R2≥0.9944). The average recovery of all impurities was between 92.6% and 103.3%. The possible production mechanism of impurities during the synthesis
and degradation processes of perampanel bulk drug was also discussed. Five impurities were analyzed by liquid chromatography–mass spectrometry (LC-MS). Moreover, two of them were simultaneously characterized by LC-MS, IR and NMR. Conclusion: The HPLC and GC methods were developed
and optimized, which could be applied for quantitative detection of the impurities, and further stability study of perampanel.
研究领域:
药物分析
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分析化学
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药学
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高影响因子
Natural Products Journal
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2019
·Vol. 9
·期 2
·138-143
·
IF 0
Li Tianyun,Dai Xiling,Li Yichen,Huang Guozheng,Cao Jianguo
Background: Stenoloma chusanum (L.) Ching is a Chinese traditional medicinal fern with high total flavonoid and total phenolic content. Traditionally, phenolic compounds were separated by using column chromatography, which is relatively inefficient. Objective: This study aims to
use an efficient method to separate natural products from S. chusanum by Medium-Pressure Liquid Chromatography (MPLC) and High-Speed Counter-Current Chromatography (HSCCC). Methods: In the present research, firstly, a sample (2.5 g) from the dichloromethane extract of S. chusanum was
separated by MPLC. Next, fraction P5 was purified by HSCCC with a two-phase solvent system composed of hexane-ethyl acetate-methanol-water (HEMWat) at a volume ratio of 2:4:1:4 (v/v/v/v). Result: Four phenolic acids were obtained and their structures were identified by means of NMR and
ESI-mass analysis. They were identified as: 1) protocatechuic acid (34 mg, purity 90.1%), 2) syringic acid (66 mg, purity 99.0%), 3) p-hydroxybenzoic acid (5 mg, purity 91.2%) and 4) vanillic acid (6 mg, purity 99.3%). Conclusion: The combination of MPLC and HSCCC is a high-efficiency
separation method for natural products. This is the first report with regard to the separation of four phenolic acids in one step by MPLC and HSCCC from S. chusanum (L.) Ching.
研究领域:
药用植物化学
·
天然产物分离纯化
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DOI
JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES
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2019
·
IF 2.813
Shang-Zhen Li,Xiang-Ming Guan,Zhao Gao,Hong-Ci Lan,Qiang Yin,Chu Chu,De-Po Yang,E-Hu Liu,Ping Zhou
Citri Reticulatae Pericarpium (CRP), the dried pericarp of Citrus reticulata Blanco, can be divided into “Guangchenpi” (GCP, the dried pericarps derived from Citrus reticulata ‘Chachi’) and “Chenpi” (CP, the dried pericarps derived from other cultivars of Citrus reticulata Blanco). To discriminate between GCP and CP, a simple and reliable high-performance thin-layer chromatography (HPTLC) method was firstly developed to analyze the volatile compound dimethyl anthranilate , and a high-performance liquid chromatography (HPLC) method was established to simultaneously quantify dimethyl anthranilate and three predominant flavonoids (hesperidin, nobiletin and tangeretin) in CRP samples. Both the HPTLC analysis and HPLC-orthogonal partial least squares discrimination analysis (OPLS-DA) indicated that GCP can be effectively distinguished from CP based on analysis of dimethyl anthranilate. Our results indicated that dimethyl anthranilate can be used as a marker compound for discrimination of GCP and CP. This work provided a convenient approach which might be applied for quality evaluation of CRP.
研究领域:
中药学
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分析化学
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DOI
PubMed
高影响因子
CHINESE CHEMICAL LETTERS
·
2011
·
IF 0.775
Pei Jin Xie,Ming Li Ye,Zhong Yang Hu,Guang Wen Pan,Yan Zhu,Jia Jie Zhang
A new method was developed for simultaneous determination of levels of AMP, ADP and ATP in blood by anion-exchange chromatography. The three adenosine phosphates were separated by Dionex IonPac AG18 (50 mm × 4 mm) guard column and IonPac AS18 (250 mm × 4 mm) analytical column using a gradient method and detected with a suppressed conductivity detector. The detection limits (S/N = 3) of AMP, ADP and ATP were 38, 47, 108 ng/L, respectively. The relative standard deviations of retention time, peak area and peak height were all less than 1.87% and a good linear relationship was obtained. This method was applied to analyze human blood samples.
研究领域:
分析化学
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医学
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产品关联
DOI
高影响因子
Journal of Marine Science and Engineering
·
2022
·Vol. 10
·期 1
·93
·
IF 2.744
Yuhua Gao,Xiaoyuan Wang,Xianwen Fang,Xuebo Yin,Lu Chen,Jianling Bi,Yao Ma,Shuai Chen
Fluorine and chlorine are important tracers for geochemical and environmental studies. In this study, a rapid alkaline digestion (NaOH) method for the simultaneous determination of fluorine and chlorine in marine and stream sediment reference samples using ion chromatography is developed. The proposed method suppresses the volatilization loss of fluorine and chlorine and decreases the matrix effects. The results are in good agreement with fluorine ~100%, chlorine ranging from 90 to 95% of the expected concentrations. The detection limits of this method were 0.05 μg/g for fluorine and 0.10 μg/g for chlorine. This method is simple, economical, precise and accurate, which shows great potential for the rapid simultaneous determination of fluorine and chlorine in large batches of geological and environmental samples commonly analyzed for environmental geochemistry studies.
研究领域:
地球化学
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环境科学
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DOI
高影响因子
FOOD CHEMISTRY
·
2015
·
IF 3.391
Chengzhu Ni,Binhe Zhu,Nani Wang,Muhua Wang,Suqing Chen,Jiajie Zhang,Yan Zhu
Honeydew is excreted by aphids as a sweet waste and nectar is floral honey. Honeydew and nectar are complicated samples which consist of various sugars and amino acids. In this work, a simple ion chromatography with column-switching method was developed for the simultaneous analysis of 8 monosaccharides and oligosaccharides in honeydew and nectar. A reversed-phase column was used as a pretreatment column to eliminate organics on-line and sugars were eluted from a collection loop to analytical column by using column-switching technique. This method showed good linearity ( r ⩾ 0.9994) and afforded low limits of detection ranging from 1.55 to 10.17 μg L −1 for all the analytes. Recoveries ranged from 95% to 105% and repeatability results were acceptable with relative standard deviation of less than 3.21% ( n = 6). This method was successfully applied to quantification of these sugars in honeydew and nectar. These results showed honeydew had much more oligosaccharides than nectar.
研究领域:
分析化学
·
植物学
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DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2025
·Vol. 192
·期 2
·1-10
·
IF 5.3
Ke Wenrui,Kuang Guochen,Gu Chuangqi,Wang Junhao,Jiang Xiao,Zhu Rongjiao,Wang Haiyuan,Zhang Zhen
A Cr-doped VO 2 nanobelt (Cr/VO 2 ) with remarkable peroxidase-like activity was synthesized and coupled with uricase to catalyze the cascade reaction for detection of uric acid. Notably, the affinity of Cr/VO 2 for 3,3',5,5'-tetramethylbenzidine dihydrochloride hydrate (TMB) and hydrogen peroxide (H 2 O 2 ) is tenfold and 20-fold higher, respectively, than that of horseradish peroxidase (HRP). The Cr/VO 2 exhibits highly reactive and stable peroxidase activity at temperatures of 20-60 ℃. Thus, the reaction catalyzed by Cr/VO 2 can be carried out at room temperature, greatly simplifying the testing process. This enzyme cascade nanozyme based colorimetric assay enables the selective and simple detection of uric acid within 30 min with a detection limit of only 0.34 μM, and has an observable potential in clinical applications. Graphical abstract
研究领域:
生物化学
·
医学诊断
·
纳米技术
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DOI
PubMed
高影响因子
Analytical Methods
·
2015
·Vol. 7
·期 6
·2653-2658
·
IF 1.821
Jing Sun,Zhaoguang Yang,Hsiaowan Lee,Lin Wang
The simultaneous separation and determination of As(III), As(V), monomethylarsenic acid (MMA), dimethylarsenic acid (DMA), Cr(III), Cr(VI) and Cd(II) in water samples have been carried out by anion exchange liquid chromatography with inductively coupled plasma mass spectrometry. Ethylenediaminetetraacetic acid was used to form negatively charged complexes with Cr(III) and Cd(II). For achieving the optimum chromatographic conditions, the effects of competing ion type, mobile phase concentration and pH on speciation have been investigated. By compromising among analysis time, chromatographic resolution and sensitivity, 40 mM ammonium nitrate at pH 8.6 has been selected as the mobile phase for real sample applications. The baseline separation of all the target species has been achieved under isocratic elution conditions. Under the optimized conditions, the limit of detection was in the range of 0.07–0.12 μg L−1 for the various species. The proposed method was applied to the determination of the target species in surface water and drinking water samples. Arsenate was the dominant arsenic species in all the tested samples. Neither MMA nor DMA was detected in real water samples. The recoveries for spikes of individual species in water samples tested ranged from 88% to 116%.
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
高影响因子
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