查找使用阿拉丁产品的科研文献

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.

Simultaneous preconcentration and quantification of ultra-trace tin and lead species in seawater by online SPE coupled with HPLC-ICP-MS

Feng Guo,Pingxiu Zeng,Jinhua Liu,Hongmei Hu,Wenbin Zhu,Yuanchao Wang,Heyong Cheng

Background Tin and lead contamination is a global threat to marine ecosystems considering their species-specific toxicity, bioavailability and mobility. Hence simultaneous measurement of multiple tin and lead compounds at μg L −1 to pg L −1 levels in environmental water is always an indispensable but challengeable task. High performance liquid chromatography coupled with inductively coupled plasma mass spectrometry (HPLC-ICP-MS) is one of the most widely used choices for this purpose because of good sensitivity, strong separation power and good compatibility. Previous HPLC-ICP-MS methods based on a single elemental speciation strategy are low-efficiency and sensitivity-insufficient for a large set of unstable samples and interaction of multiple metal(loid)s down to ng L −1 levels. Results In this study, we developed a sensitive, efficient and environment-friendly analytical method for accurate quantification of inorganic and organic species of tin and lead simultaneously based on HPLC-ICP-MS with online integration of solid phase extraction (SPE). By using graphene oxide modified silica conditioned with 1 mM benzoic acid to enrich tin and lead species from 10 mL sample, detection limits were improved to 2–8 pg per liter due to satisfactory enrichment factors (522−2848 folds). The SPE-HPLC-ICP-MS method was applicable to quantification of ultra-trace tin and lead species at pg L −1 levels in uncontaminated seawater . Tributyltin was the only tin species detected at subnanograms per liter levels while Pb(II) was the only lead species detected at several nanograms per liter in thirteen coastal seawater samples collected in Hangzhou Bay, indicating light contamination of tin and lead. Significance Overall, the proposed SPE-HPLC-ICP-MS method is highly sensitive, efficient and environment-friendly that are fairly suitable to routine speciation analysis of tin and lead in environmental, food, and biological samples.

Simultaneous quantification of 12 water-soluble vitamins in MDCK cell culture media by eco-friendly ion-pairing reagent-free HPLC-UV

Zhou Lei,Zhang Mengting,Sun Huinan,Duan Liyuan,Meng Qingwei

This study establishes the first reversed-phase HPLC-UV method for simultaneous baseline separation of 12 structurally diverse water-soluble vitamins (WSVs) within 25 min. The eco-friendly approach utilizes a methanol–potassium dihydrogen phosphate (pH 4.85) gradient on a ChromCore C18 column (250 × 4.6 mm, 5 μm) with dual-wavelength detection (210/266 nm), eliminating environmentally detrimental ion-pairing reagents. Rigorous validation per ICH Q2(R1) guidelines confirmed excellent linearity (R² > 0.999), precision (RSD < 2.1%), accuracy (spike recoveries: 93.9–106.8%), and sensitivity (LODs: 0.01–0.78 µg/mL). The method resolved key analytical challenges including polarity disparities, matrix interference, and vitamin instability. Successful quantification of endogenous vitamins in DMEM medium showed ≤ 5.1% deviation from certified values for 11/12 analytes. Applied to five commercial MDCK cell culture media, the method revealed significant inter-product variability in vitamin composition – notably universal under-supplementation of riboflavin (0.576–0.741 µg/mL, 10× lower than other vitamins) and inconsistent biotin/adenine supplementation. This robust, cost-effective platform provides biomanufacturers with a powerful quality control tool for optimizing vitamin supplementation in vaccine production systems, addressing a critical gap in cell culture analytics.

Highly efficient analysis of fipronil and ethiprole in milk using ternary deep eutectic solvent-functionalized UiO-66-based tip-SPE − HPLC

Yehong Han,Ruiyang Ma,Juntao Wang,Hongyuan Yan,Yufei Shan,Zihan Liu,Zhi Wang

In this study, for the effective determination of fipronil and ethiprole residues in milk, a new analytical approach, which was based on a tip solid-phase extraction (TSPE) by using a newly prepared ternary deep eutectic solvent-functionalized UiO-66 (TDES@UiO-66) as the adsorbent and HPLC-UV detection, was developed. The method integrated the advantages of both the high adsorption capability of the TDES@UiO-66 and the high efficiency of the TSPE, and enabled a rapid extraction of fipronil and ethiprole from milk samples within 8 min by utilizing only 3.0 mg of TDES@UiO-66 adsorbent. The developed method demonstrated an excellent analytical performance, including good linearity (linear rang: 0.02–10 μg/mL; r : 0.9990–0.9997), high precision (relative standard deviations: ≤ 9.9 %), good accuracy (recoveries: 91.1 %–109.8 %), and good sensitivity (limits of quantification: 0.011–0.018 μg/mL). This study provides a rapid and practical approach for the detection of fipronil and ethiprole in different milk samples.

Preparation of magnetic amphiphilic resin microspheres via the one-step polymerization method and extraction of four glucocorticoids for HPLC–MS analysis

Zibo Zhou,Liang He,Tianyi Wang,Hongzhen Tang,Suzi Qin,Xueyan Nan,Wenbo Cheng,Haibo He,Pengli Bai

Amphiphilic materials can be used for sample preparation of chromatography or mass spectrometry. Amphiphilic materials with magnetic properties in combination with magnetic suction devices allow for automated sample preparation. However, conventional synthesis methods are cumbersome and not suitable for the mass production of the material. In this study, a micro-suspension polymerization method was developed to synthesize magnetic amphiphilic resin microspheres (MARMs), providing new ideas for the preparation of amphiphilic microspheres. MARMs with particle sizes ranging from 3 to 6 μm were successfully prepared, with BET surface area up to 653.2 m 2 /g. A magnetic solid-phase extraction method based on MARM-5 was developed for the extraction of four glucocorticoids including Cortisone, Hydrocortisone, Cortodoxone, and Corticosterone. This method had a very short adsorption time of 0.5 min and a total extraction time of only 13 min. The limit of detection for the four glucocorticoids ranged from 0.22 to 0.82 ng/L. There was a good linear relationship between sample concentration and peak area in the range of 25∼500 ng/L. Relative recovery of 98 %∼108 % and internal standard normalized matrix effect factors of 95∼114 % were obtained, and the relative standard deviation was between 2.3 % and 6.3 %. The MARMs would be used as excellent solid extraction material for glucocorticoids.

Determination of six volatile fatty acids in human serum, urine and faeces by low temperature derivatisation combined with HPLC–MS/MS

Qian Li,Yongfu Zeng,Lianfeng Ai,Maolin Wei,Xiaomeng Liu,Xiaochan Zhao,Haoran Zhang,Xiujuan Guo

A stable isotope dilution-liquid chromatography tandem mass spectrometry method based on a low-temperature derivatization strategy with 3-nitrophenylhydrazine (3-NPH) was developed for the determination of six volatile fatty acids (VFAs) in serum, urine, and feces. Ice acetonitrile was used to precipitate proteins and extract the target analytes. The extract was derivatized with 3-NPH methanol solution at 4 °C. BEH C8 (1.7 μm, 2.1 × 100 mm) column was used for chromatographic separation, and acetonitrile–water (both containing 0.01 % formic acid) were used as the mobile phase with a gradient elution of 10 min. Electrospray ionization source (ESI) in negative ion multiple reaction monitoring (MRM) mode were used for analyte detection. The regression coefficients R 2 of the calibration curves for the six VFAs were in the range of 0.9963–0.9994, and the LOQs were in the range of 0.02–0.5 μg mL −1 , with the recoveries in the range of 85.3–104.3 %, and the intra- and inter-day precision in the range of 1.8–9.1 %. The method is simple, accurate and reliable, and has been applied in the sensitive determination of VFAs in complex biological samples.

Determination of Synthetic Phenolic Antioxidants in Edible Oils: A Vortex-Assisted Hydrophilic DES-LLME/HPLC Approach with Focus on PG and TBHQ

Xiaoqi Liu,Chenjia Jiang,Haodong Zhou,Yunfeng Yuan,Jinhua Zhu,Xiuhua Liu,Md. Zaved H. Khan,Minghua Lu

Synthetic phenolic antioxidants PG (propyl gallate), TBHQ (tert-butyl hydroquinone), BHA (butyl hydroxyanisole) are commonly used additives in edible oils, but excessive residues may pose health risks. Conventional detection methods suffer from high organic solvent consumption, complex pretreatment procedures, and environmental concerns. To address these limitations, this study developed a rapid, green and efficient analytical method combining deep eutectic solvent (DES)-based liquid-liquid microextraction (LLME) with high-performance liquid chromatography (HPLC) for the rapid determination of phenolic antioxidants in edible oils. Using an optimized hydrophilic DES system composed of choline chloride and 1,3-butanediol, (molar ratio 1:2), along with simplified extraction conditions (780 μL DES, 11 s vortex at room temperature), efficient extraction and enrichment of the target analytes were achieved. The method demonstrated excellent performance specifically for PG and TBHQ, exhibiting a wide linear range (1-400 μg/mL, R² > 0.9970), low limits of detection (0.12-0.28 μg/mL), satisfactory spiked recoveries (90.2 %-113 %), and good intra-day and inter-day precision (RSD < 5.0%). Analysis of real samples demonstrated that the proposed method is highly sensitive, operationally simple, and environmentally friendly for the analysis of PG and TBHQ, offering a promising alternative for rapid monitoring and food safety regulation of these two antioxidants in edible oils. It should be noted that the current hydrophilic DES system did not achieve optimal extraction efficiency for BHA, highlighting the need for further optimization toward a comprehensive multi-analyte approach.

Facile synthesis of ternary magnetic chitosan-graphene oxide composites for efficient extraction of urinary modified nucleosides prior to HPLC-MS/MS analysis

Qiao Deng,Jianliang Li,Jingjing Xu,Xiaojing Zhao,Dan Wei,Xu Wang

The accurate quantification of urinary modified nucleosides, promising non-invasive cancer biomarkers, is hindered by their trace concentrations and complex matrix interference. To overcome this challenge, we developed the facile synthesis of a novel ternary magnetic composite (MCS-100GO) by integrating chitosan (CS) and graphene oxide (GO) onto the magnetic core, utilized as adsorbent for magnetic solid-phase extraction (MSPE). The adsorbent leverages the combined effects of hydrogen bonding (from CS and GO) and π-π interactions (from GO) for highly efficient capture, while the magnetic core enables rapid and simple separation. Systematic optimization demonstrated exceptional performance for 3-methylcytidine (m 3 C) and 7-methylguanosine (m 7 G). The MCS-100GO composite achieved rapid adsorption equilibrium (3 min), high maximum adsorption capacities (0.7730 mg/g for m 3 C and 0.7561 mg/g for m 7 G). The developed MCS-100GO based MSPE-HPLC-MS/MS method, validated according to FDA guidelines, exhibited excellent sensitivity (LODs: 0.015–0.030 μg/L), a wide linear range (0.050–50 μg/L; R 2 > 0.9995), and high precision (RSD < 6.4 %). Furthermore, parallelism experiments with a coefficient of variation (CV) of 9.7 % confirmed no significant matrix effects. Compared to existing methods, this approach offers a superior balance of low adsorbent dosage, sensitivity, speed, presenting a promising and efficient strategy for high-throughput analysis of urinary nucleoside biomarkers.

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.

Biopharmaceutics and Pharmacokinetics of Timosaponin A-III by a Sensitive HPLC-MS/MS Method: Low Bioavailability Resulting from Poor Permeability and Solubility

Wang Hai-Qiao,Gong Xiao-Mei,Lan Fen,Zhang Yi-Han,Xia Jin-Er,Zhang Hai,Guo Jia-Lin,Liu Min

Background: Timosaponin A-III is one of the most promising active saponins from Anemarrhena asphodeloides Bge. As an oral chemotherapeutic agent, there is an urgent need to clarify its biopharmaceutics and pharmacokinetics to improve its development potential. Objective: This research explores the bioavailability of timosaponin A-III and clarifies its absorption and metabolism mechanisms by a sensitive and specific HPLC-MS/MS method. Methods: Pharmacokinetics and bioavailability studies of timosaponin A-III were performed in Sprague- Dawley rats by oral (20 mg/kg) and intravenous administration (2 mg/kg). Control group was given the same volume of normal saline. The absorption of timosaponin A-III was investigated in a rat intestinal perfusion model in situ and a Caco-2 cell transport model in vitro. The metabolic rate of timosaponin A-III was determined in a rat liver microsome incubation system. Results: After the oral administration, timosaponin A-III reached Cmax of 120.90 ± 24.97 ng/mL at 8 h, and the t1/2 was 9.94 h. The absolute oral bioavailability of timosaponin A-III was 9.18%. The permeability coefficients of timosaponin A-III in four intestinal segments ranged from 4.98 to 5.42 10-7 cm/s, indicating a difficult absorption. A strikingly high efflux transport of timosaponin A-III was found, PappBA 3.27 ± 0.64 10−6 cm/s, which was abolished by a P-gp inhibitor. Rat liver microsome incubation studies showed that timosaponin A-III could hardly be metabolized, with a t1/2 of over 12 h. In addition, the solubility test showed a low solubility in PBS solution, i.e. 30.58 μg/mL. Conclusion: Timosaponin A-III exhibited low oral bioavailability by oral and intravenous administration, which was probably caused by its low permeability and solubility. This study may provide a reference for its rational clinical use and further study on the pharmacology or toxicology of timosaponin A-III.

Synthesis of fully porous silica microspheres with high specific surface area for fast HPLC separation of intact proteins and digests of ovalbumin

Xia Hongjun,Wang Lin,Li Chunyang,Tian Boshi,Li Qingfeng,Zhao Hui,Bai Quan

Fully porous silica microspheres (FPSM) with high specific surface area and hierarchical pore as matrix for HPLC were prepared. First, the porous silica nanospheres with controllable particle size and pore diameter were successfully synthesized using a dual-templating approach, the pore size of nanospheres can be increased to 18.4 nm by changing the molar ratios of octyltrimethylammonium bromide (TOMAB) and cetyltrimethyl ammonium bromide (CTAB), which is suitable for separation and analysis of biomolecules without pore enlargement. Then, the micron FPSM with hierarchical pore were synthesized by polymerization-induced colloid aggregation (PICA) using the porous nanospheres as a silicon source, which has a large mesoporous structure (35.2 nm) and high specific surface area (560 m 2  g −1 ). Subsequently, the FPSM modified with octadecyltrichlorosilane were studied as stationary phase for separation of cytochrome C, lysozyme, ribonuclease A, and ovalbumin, bovine serum albumin, and the baseline separation of five proteins was achieved within 1 min. The prepared column was also applied to the fast separation of digests of ovalbumin, and more chromatographic peaks were obtained compared to a commercial column under the same gradient elution conditions. In addition, the static-binding capacity of the functionalized FPSM for bovine serum albumin (BSA) was measured to be 276 mg g −1 , which was nearly twice the static adsorption given in literature. Therefore, these FPSM with high specific surface area and hierarchical pore structure are expected to have great potential for the separation of complex biological samples using HPLC. A synthetic strategy was provided towards FPSM with hierarchical pores and high specific surface area using porous nanospheres as silicon source. The outstanding performance of the FPSM is that it has a high specific surface area while maintaining a large mesoporous size, which overcomes the disadvantage of sacrificing the specific surface area when increasing the pore size of porous silica microspheres prepared by using the traditional PICA method.