查找使用阿拉丁产品的科研文献

Targeted metabolites analysis and variety discrimination of Wuyi rock tea by using a whole-process chemometric-assisted HPLC-DAD strategy

Yue-Yue Chang,Hai-Long Wu,Tong Wang,Huan Fang,Xiao-Zhi Wang,Sengsavanh Khanthavong,Phimphone Keobountham,Ru-Qin Yu

As the China’s top-ranked oolong tea, there are many varieties of Wuyi rock tea (WRT) in the market. The prices of different varieties vary greatly, and the differential chemical composition is unclear. Therefore, we developed a rapid and systematic chemometrics-assisted HPLC–DAD strategy for targeted metabolites analysis and variety discrimination of WRT. The strategy involved design of experiment , targeted metabolites quantification, varieties discrimination and differential component screening. Specifically, optimal extraction conditions of WRT are obtained by response surface methodology-Box-Behnken design method. Then, 22 targeted metabolites are rapidly and accurately quantified by alternate trilinear decomposition algorithm (ATLD) with average spiked recoveries ranging from 85.4% to 108.6%. Finally, the four WRT varieties (110 samples) are discriminated by linear discriminant analysis (LDA) and partial least squares-discriminant analysis (PLS-DA) with relative concentration results as model input. The correct classification rates obtained by PLS-DA are greater than 88%, especially for high-quality “Niulankeng rougui” tea, its specificity and sensitivity are 100%. Moreover, ten differential metabolites related to identification are screened by variable importance in projection (VIP). This work scientifically and comprehensively elaborates the whole-process of WRT analysis, which can become a comprehensive food analysis strategy for the purpose of precise quantification and pattern recognition.

Identification of 13 natural antioxidants in green calyx plum using AAPH, ABTS, and FRAP-coupled HPLC-DAD via QTOF-MS/MS

Jing-Wen Hao,Wei-Ting Wang,Nai-Dong Chen,Yan Shen

The novel application of a combined screening method, utilizing AAPH, ABTS, and FRAP assays with HPLC, is first used for screening natural antioxidants in Green Calyx plums (GCP). This method was assumed that the peak areas of compounds with antioxidant activity in HPLC chromatograms would be significantly reduced or disappeared after incubating with the AAPH, ABTS, and FRAP. The thirteen screened antioxidants can be identified by Q-TOF-MS/MS. kaempferol-3-O-rutinoside, narcissoside, and astragalin were first reported in GCP. respectively. The thirteen screened antioxidants were quantified simultaneously at their maximum absorption wavelengths, with concentrations ranging from 0.61 to 79.30 mg/g across three distinct flowering stages. Furthermore, the in vitro activity and molecular docking of oxidative stress-related enzyme xanthine oxidase (XOD) were utilized to evaluate the antioxidant capacity of the screened compounds. Consequently, our method effectively screens for antioxidants within complex mixtures, positioning GCP as a promising reservoir of natural bioactive compounds.

Sensitive detection of phthalates in Chinese Baijiu by online in-tube SPME-HPLC-DAD based on carbonized COF-coated carbon fibers

Yaming Sun,Baoen Su,Ke Zhang,Yuhong Lin,Bing Wang,Min Sun

The monitoring of phthalates (PAEs) is essential for ensuring the quality and safety of Chinese Baijiu. However, the complex matrices and low level pose significant technical challenges. Herein, an online in-tube solid-phase microextraction coupled with high-performance liquid chromatography-diode array detector (IT-SPME-HPLC-DAD) was proposed for detecting PAEs in Baijiu. A covalent organic framework was grown onto carbon fibers, then the material was carbonized to get another fibers (CFs@C-COF). The CFs@C-COF as a sorbent of IT-SPME demonstrated enhanced physicochemical properties, including highly a graphitized structure with mild defects, a high surface area, abundant mesopores and excellent durability. The superior extraction efficiency of CFs@C-COF for PAEs can be ascribed to multiple interactions, such as hydrophobic, π-stacking, and pore-filling effects. The developed online IT-SPME-HPLC-DAD method exhibited the linear ranges (1.0–10.0, 1.5–10.0 μg L −1 ), the limits of detection (0.3–0.5 μg L −1 ), acceptable relative recoveries (72.7 %–125.8 %), and satisfactory repeatability. In addition, the total duration of this online extraction procedure was only 23 min and no any pretreatment of the samples was required except for diluting Baijiu samples. This research not only offered a simple and effective strategy for the analysis of Baijiu but also expanded the application of carbonized COFs in food safety.

Simultaneous and specific enrichment of several amphenicol antibiotics residues in food based on novel aptamer functionalized magnetic adsorbents using HPLC-DAD

Shengfeng Huang,Ning Gan,Haibo Liu,You Zhou,Yinji Chen,Yuting Cao

In this work, a novel aptamer functionalized magnetic adsorbent was developed and combined with magnetic dispersive solid phase extraction (MDSPE) for selective enrichment of several amphenicol antibiotics residues (chloramphenicol(CAP), thiamphenicol(TAP) and florphenicol(FF)) in foodstuff then determined by High Performance Liquid Chromatography (HPLC)-Diode array detector(DAD). Firstly, a magnetic silica-coated Fe 3 O 4 microsphere(Fe 3 O 4 @SiO 2 ) was synthetized by sol-gel method, then it was functionalized by amino groups through 3-Aminopropyltriethoxysilane (APTES) reagent to form Fe 3 O 4 @SiO 2 -NH 2 ; Thirdly, the amino group on Fe 3 O 4 @SiO 2 -NH 2 was transferred to carboxylic group via the succinic anhydride to form Fe 3 O 4 @SiO 2 -COOH. Finally a kind of DNA aptamer with amino group which can simultaneously recognize CAP, TAP, FF, was functionalized on Fe 3 O 4 @SiO 2 -COOH through adding the EDC/sulfo-NHS coupling reagent (Fe 3 O 4 @SiO 2 @Apt). Therefore, a very stable and useful adsorbent was synthesized for the detection of chloramphenicol series antibiotics. This adsorbent can specifically and simultaneously recognize and enrich CAP, TAP, and FF with high adsorption amount from some complicated food matrix, e.g. milk based on the high affinity of aptamer towards the analytes. The saturated extraction capacities for CAP, TAP and FF by the adsorbent were 2.82, 2.56, 2.72   μg/g (mass of target/adsorbent)respectively and the enrichment folds were more than 100 times. Afterwards, the target analytes were washed away by pH 8.5 0.1   M Tris-HCl buffer solution and detected by HPLC-DAD. The parameters including extraction temperature, extraction capacity, extraction & desorption pH, extraction & desorption time were investigated. With the optimized conditions, the limits of detection (LOD) and limits of quantitation (LOQ) were 0.12–0.17   ng/ml and 0.40–0.55   ng/ml for the amphenicols in milk. The adsorbent also has good reproducibility for extraction which can be reused at least for 60 cycles with the recovery over 80% (Fig. S2). The MDSPE combined with HPLC-DAD detection possessed the advantages of high selectivity, extraction capacity and very convenient for magnetic separation. In addition, this method is environment friendly and employed no organic solution in the period of pretreatment and extracting. It is a universal platform which can be extended to selective enrichment other organic pollutants residues if changing the modified aptamers.

Rapid and Sensitive Detection of Multi-Class Food Additives in Beverages for Quality Control by Using HPLC-DAD and Chemometrics Methods

Sun Xiao-Dong,Wu Hai-Long,Liu Zhi,Chen Yue,Liu Qian,Ding Yu-Jie,Yu Ru-Qin

A rapid and sensitive analytical strategy combining high-performance liquid chromatography-diode array detection (HPLC-DAD) and chemometrics methods was developed for the determination of multi-class food additives in a variety of beverage samples. Different kinds of beverages, which contain diverse unknown interferences, can be directly injected into a chromatographic system after a simple dilution or pretreatment step, and the data were recorded in a short time under a simple gradient elution mode. Although peaks overlapped and changeable interferences existed in the dimension of the chromatographic and spectral in real beverages, all food additives were accurately resolved by using a second-order calibration method based on alternating trilinear decomposition (ATLD) algorithm, and accurate chromatographic profiles, spectral profiles, and concentration profiles were also obtained. Limits of detection for all additives were between 1.40 and 165.1 ng mL −1 , while limits of quantitation ranged from 4.20 to 500.2 ng mL −1 . The spiked recoveries were in the range of 87.3–103% (except amaranth) with RSDs less than 10.2%. Compared with the results obtained by classic HPLC method, our proposed method was more accurate. In all, the proposed method is fast, sensitive, and universal and could be used as a reliable tool to determine food additives and quality monitoring in different complex beverages.

A novel chemometric coupling technique combined with HPLC-DAD for rapid quantification and source apportionment of monoaromatic hydrocarbons in soil samples

Zhen Zhang,You Wang,Xueqi Li,Xinran Wu,Yunyi Hu,Rong An,Ling Xu,Xiangdong Qing

In the contribution, a novel chemometric coupling technique combined with high-performance liquid chromatography with diode array detector (HPLC-DAD) was developed for the rapid quantification and source apportionment of eight monoaromatic hydrocarbons (MACHs) in soil samples. The strategy was built on the three-dimensional calibration based on alternating trilinear decomposition coupling with the unsupervised classification using t-distributed stochastic neighbor embedding (named ATLD-t-SNE). Firstly, a validation set and a spiked soil set were used to investigate the quantitative performance of the developed method. The obtained average recoveries of eight MACHs in soil samples were between (95.0 ± 4.4)% and (111.9 ± 3.3)%, and the limits of detection ranged from 0.0041μg mL −1 to 1.85 μg mL −1 , which were better than the results of parallel factor analysis-alternating least squares (PARAFAC-ALS). Subsequently, the proposed approach was applied to analyze actual soil samples collected from tea plantations (7 samples) and industrial areas (60 samples), revealing the presence of ethylbenzene (EBZ) and (1,3,5)-trimethylbenzene (MTY) in both types of soil samples, could the absence of other six MACHs. Finally, ATLD-t-SNE was utilized to classify these soil samples and a comparison between the new strategy and ATLD combined with feature component analysis as well as principal component analysis (called ATLD-FCA and ATLD-PCA, respectively) was made. The finding indicated that ATLD-t-SNE provided better clustering than other two methods, indicating different sources of organic pollution of MACHs in soil samples.

Quantitative Analysis of Six Phenolic Acids in Artemisia capillaris (Yinchen) by HPLC-DAD and Their Transformation Pathways in Decoction Preparation Process

Fang Tian,Qun-Jia Ruan,Ying Zhang,Hui Cao,Zhi-Guo Ma,Gai-Lian Zhou,Meng-Hua Wu

We aimed to establish a quantitative analysis method of six constituents (5-caffeoylquinic acid, 3-caffeoylquinic acid, 4-caffeoylquinic acid, 1,3-dicaffeoylquinic acid, 3,4-dicaffeoylquinic acid, and 4,5-dicaffeoylquinic acid) in Artemisia capillaris (Yinchen) and its decoction by using HPLC coupled with DAD. Besides, the transformation paths of the six constituents were analyzed in decoction preparation processing. The analytical method was fully validated in terms of linearity, sensitivity, precision, repeatability, and recovery and applied to assess the transformation trend and quantitative analysis of the six constituents in Yinchen decoction. The contents of six constituents varied greatly in Yinchen herb and Yinchen decoction, and there were inextricable internal relationships between them. Presumably 3-caffeoylquinic acid was isomerized to generate 5-caffeoylquinic acid and 4-caffeoylquinic acid. Similarly, 1,3-dicaffeoylquinic acid and 3,4-dicaffeoylquinic acid were produced by isomerization of 4,5-dicaffeoylquinic acid. In conclusion, this study provides a chemical basis for quality control of Yinchen decoction, and the changes of selected markers in decoction could give us some novel perspectives to study the relationship between substances and drug efficacy.

A sensitive and rapid HPLC-DAD method for the determination of 3-hydroxy-1,2-dimethyl-4-pyridone and its distribution in rats

Mengdi Chen,Xuejiao Zhang,Shuling Li,Qiongyao Zhang

Differentiating grades of Xihu Longjing teas according to the contents of ten major components based on HPLC-DAD in combination with chemometrics

Hui-Wen Gu,Xiao-Li Yin,Ying-Xiang Ma,Jing Wang,Fan Yang,Weiqing Sun,Baomiao Ding,Ying Chen,Zhi Liu

A new chemometrics-assisted high performance liquid chromatography-diode array detection (HPLC-DAD) method was developed to rapidly quantify ten major components in nine Xihu Longjing tea samples. This new strategy proved to be a useful tool for handling the co-eluted problems during chromatographic analysis and enabled the quantification of ten major components in tea samples within only 10 min. The average recoveries of these analytes in tea samples ranged from 100.0% to 112.7% except (−)-epigallocatechin gallate (EGCG). The relative standard deviations of intra- and inter-day assays were in the range of 0.14%–5.09% for all the ten analytes. Furthermore, the quantitative results were used as input variables to perform principal component analysis (PCA) and hierarchical cluster analysis (HCA) for differentiating tea grades. Results demonstrated that the nine different grades of Xihu Longjing tea samples were successfully divided into three categories. This study showed that it is possible to perform tea grades differentiation according to the contents of major components using chemometric pattern recognition methods.

Metal organic frameworks (MOFs) for magnetic solid-phase extraction of pyrazole/pyrrole pesticides in environmental water samples followed by HPLC-DAD determination

Jiping Ma,Zhidan Yao,Liwei Hou,Wenhui Lu,Qipeng Yang,Jinhua Li,Lingxin Chen

Magnetic metal-organic frameworks (MOFs, [MIL-101]) were prepared and used as magnetic solid-phase extraction (MSPE) adsorbents for preconcentration of four kinds of pyrazole/pyrrole pesticides (flusilazole, fipronil , chlorfenapyr , and fenpyroximate) in environmental water samples, followed by high-performance liquid chromatography-diode-array detector (HPLC-DAD) determination. Several variables affecting MSPE efficiency were systematically investigated, including amount of MIL-101, extraction time, sample pH, salt concentration, type of desorption solvent and desorption number of times. Under optimized conditions, excellent linearity was achieved in the range of 5.0–200.0   μg/L for flusilazole and fipronil, and 2.0–200.0   μg/L for chlorfenapyr and fenpyroximate, with correlation coefficients r >0.9911. Limits of detection and quantification were 0.3–1.5   μg/L and 1.0–5.0   μg/L, respectively. The intra-day and inter-day precision (relative standard deviation, n =6, %) at three spiked levels were 1.1–5.4% and 3.9–7.8% in terms of peak area, respectively. The method recoveries at three fortified concentration levels ranged from 81.8% to 107.5% for reservoir water samples, 81.0–99.5% for river water samples, and 80.2–106.5% for seawater samples. The developed MOFs based MSPE coupled with HPLC method proved to be a convenient, rapid and eco-friendly alternative to the sensitive determination of pyrazole/pyrrole pesticides with high repeatability and excellent practical applicability.

Layered porous organic frameworks as a novel adsorbent for the solid phase extraction of chlorophenols prior to their determination by HPLC-DAD

Wang Qianqian,Li Gaigai,Wang Chun,Wu Qiuhua,Wang Zhi

A layered porous organic framework (L-POF) with high surface area and porous volume was used as a novel adsorbent for adsorption of chlorophenols (CPs). The L-POF showed much higher adsorption capacity for four CPs (2-CP, 3-CP, 2,3-CP, 2,4-CP) compared with corresponding amorphous POF and some commercial adsorbents. Then, an L-POF-based solid-phase extraction method combined with high-performance liquid chromatography for analyzing CPs at the wavelength of 280 nm in water and honey samples was established. Under the optimum conditions, four CPs exhibited good linearity in the range 0.10–80.0 ng mL −1 for water and 2–400 ng g −1 for honey samples with determination coefficient r 2  > 0.996. The method has low limits of detection of 0.03–0.10 ng mL −1 for water and 0.5–1.0 ng g −1 for honey samples. The method presented satisfactory precision and accuracy with relative standard deviations ≤ 7.8% and recoveries of 80–115%. High enrichment factors of 123–190 for water and 63–97 for honey were obtained. The validated method was successfully used to determine CPs in water and honey samples. The L-POF also displayed prominent adsorption performance for many other dyes and organic contaminants. This suggests that it can be an ideal candidate as adsorbent for wide application in separation and analysis. Graphical Abstract

Simultaneous and rapid screening and determination of twelve azo dyes illegally added into food products by using chemometrics-assisted HPLC-DAD strategy

Ming-Yue Dong,Hai-Long Wu,Wan-Jun Long,Tong Wang,Ru-Qin Yu

Edible colorants, as an essential external condition of food products, can increase people’s appetite. Some businesses have used some cheap and illegal dyes instead of edible colorants to gain benefits. It not only deceives consumers, but also seriously endangers their health. In this work, two chemometric algorithms assisted high-performance liquid chromatography with diode array detection (HPLC-DAD) were proposed for screening and quantifying twelve azo dyes illegally added into different food products. All analytes were successfully eluted within 6.5 min. With the aid of the prominent “second-order advantage” of the chemometric algorithms, the overlapping peaks and unknown interferences were solved. The spiked average recoveries obtained by alternating trilinear decomposition (ATLD) and multivariate curve resolution-alternating least squares (MCR-ALS) were 82.8–111.5% with standard deviation (SD) less than 6.5% and 78.7–122.6% with SD less than 18.7%, respectively. The limits of detection were 0.01–2.56 mg kg −1 and 0.01–2.95 mg kg −1 , respectively. The results indicated that two algorithms had practical value for the simultaneous and rapid screening and determination of azo dyes in food products. Compared with other methods based on HPLC, the proposed method could flexibly handle different interferences, and had the advantages of high efficiency, simple operation and being environmentally friendly.