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Li M, Wang J, Zhang C, Zhao X, Xiong Y, Cao Y, Wang D, Li X, Liang X, Qing G. Single-Molecule Identification and Quantification of Steviol Glycosides with a Deep Learning-Powered Nanopore Sensor. ACS NANO 2024; 18:25155-25169. [PMID: 39189792 DOI: 10.1021/acsnano.4c07038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/28/2024]
Abstract
Steviol glycosides (SGs) are a class of high-potency noncalorie natural sweeteners made up of a common diterpenoid core and varying glycans. Thus, the diversity of glycans in composition, linkage, and isomerism results in the tremendous structural complexity of the SG family, which poses challenges for the precise identification and leads to the fact that SGs are frequently used in mixtures and their variances in biological activity remain largely unexplored. Here we show that a wild-type aerolysin nanopore can detect and discriminate diverse SG species through the modulable electro-osmotic flow effect at varied applied voltages. At low voltages, the neutral SG molecule was drawn and stuck in the pore entrance due to an energy barrier around R220 sites. The ensuing binding events enable the identification of the majority of SG species. Increasing the voltage can break the barrier and cause translocation events, allowing for the unambiguous identification of several pairs of SGs differing by only one hydroxyl group through recognition accumulation from multiple sensing regions and sites. Based on nanopore data of 15 SGs, a deep learning-based artificial intelligence (AI) model was created to process the individual blockage events, achieving the rapid, automated, and precise single-molecule identification and quantification of SGs in real samples. This work highlights the value of nanopore sensing for precise structural analysis of complex glycans-containing glycosides, as well as the potential for sensitive and rapid quality assurance analysis of glycoside products with the use of AI.
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Affiliation(s)
- Minmin Li
- State Key Laboratory of Medical Proteomics, National Chromatographic R. & A. Center, CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
| | - Jing Wang
- State Key Laboratory of Medical Proteomics, National Chromatographic R. & A. Center, CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Chen Zhang
- Jiangxi Provincial Key Laboratory for Pharmacodynamic Material Basis of Traditional Chinese Medicine, Ganjiang Chinese Medicine Innovation Center, Nanchang 330000, P. R. China
| | - Xinjia Zhao
- State Key Laboratory of Medical Proteomics, National Chromatographic R. & A. Center, CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
| | - Yuting Xiong
- State Key Laboratory of Medical Proteomics, National Chromatographic R. & A. Center, CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
- Dalian Lingshui Bay Laboratory, Dalian 116023, P. R. China
| | - Yuchen Cao
- State Key Laboratory of Medical Proteomics, National Chromatographic R. & A. Center, CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Dongdong Wang
- State Key Laboratory of Medical Proteomics, National Chromatographic R. & A. Center, CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
| | - Xiaonong Li
- Jiangxi Provincial Key Laboratory for Pharmacodynamic Material Basis of Traditional Chinese Medicine, Ganjiang Chinese Medicine Innovation Center, Nanchang 330000, P. R. China
| | - Xinmiao Liang
- State Key Laboratory of Medical Proteomics, National Chromatographic R. & A. Center, CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
- Jiangxi Provincial Key Laboratory for Pharmacodynamic Material Basis of Traditional Chinese Medicine, Ganjiang Chinese Medicine Innovation Center, Nanchang 330000, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Guangyan Qing
- State Key Laboratory of Medical Proteomics, National Chromatographic R. & A. Center, CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
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El-Sayed A, Sabry MA, Elmansi H, Eid M, Shalan S. Stability indicating eco-friendly quantitation of terbutaline and its pro-drug bambuterol using quantitative proton nuclear magnetic spectroscopy. BMC Chem 2024; 18:25. [PMID: 38291471 PMCID: PMC10829239 DOI: 10.1186/s13065-024-01120-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Accepted: 01/10/2024] [Indexed: 02/01/2024] Open
Abstract
Quantitative 1H-NMR became an increasingly important issue in pharmaceutical analytical chemistry. This study used NMR spectroscopy to assay the bronchodilator drug terbutaline sulfate and its pro-drug bambuterol hydrochloride in pure form and pharmaceutical preparations. The technique proceeded using deuterium oxide (D2O) as an 1H-NMR solvent and phloroglucinol anhydrous as an internal standard (IS). Comparatively, to the phloroglucinol signal at 5.9 ppm, the resulting quantitative signals of the studied drugs were corrected. The terbutaline singlet signal at 6.3 ppm was chosen for quantification, while the bambuterol quantitative singlet signal was at 2.9 ppm. The two drugs were rectilinear over the concentration range of 1.0-16.0 mg/mL. LOD values were 0.19 and 0.21 mg/mL while LOQ values were 0.58 and 0.64 mg/mL for terbutaline and bambuterol respectively. The developed method has been validated according to the International Conference of Harmonization (ICH) regarding linearity, accuracy, precision, specificity, and robustness. A greenness profile assessment was applied, and the method proved to be green. The method enables the assay of the two drugs in pure drug and pharmaceutical preparations. The method also enables the assay of the two drugs in the presence of each other; thus, it is considered a stability-indicating method where terbutaline is an acid degradation product of bambuterol.
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Affiliation(s)
- Asmaa El-Sayed
- Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Mansoura University, Mansoura, 35516, Egypt.
| | - Mohamed A Sabry
- Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Mansoura University, Mansoura, 35516, Egypt
| | - Heba Elmansi
- Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Mansoura University, Mansoura, 35516, Egypt
| | - Manal Eid
- Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Mansoura University, Mansoura, 35516, Egypt
| | - Shereen Shalan
- Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Mansoura University, Mansoura, 35516, Egypt
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Dong H, Huang R, Gao L, Yang Y, Xu X, Nie L, Li L, Dong Q, Zhang H, Xu J, Sun J, Zang H. Research on nonlinear quantification of Rebaudioside A crystallization process based on near-infrared sensor fusion. J Pharm Innov 2022. [DOI: 10.1007/s12247-022-09679-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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MUMCU A. A simple and feasible quantification of metabolites in the human follicular fluid using 1H HR-MAS NMR spectroscopy. JOURNAL OF THE TURKISH CHEMICAL SOCIETY, SECTION A: CHEMISTRY 2021. [DOI: 10.18596/jotcsa.986523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Khalil A, Kashif M. Nuclear Magnetic Resonance Spectroscopy for Quantitative Analysis: A Review for Its Application in the Chemical, Pharmaceutical and Medicinal Domains. Crit Rev Anal Chem 2021; 53:997-1011. [PMID: 34752175 DOI: 10.1080/10408347.2021.2000359] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/21/2023]
Abstract
Nuclear magnetic resonance (NMR) is a rapid and accurate analytical tool for qualification and quantification. The capacity of NMR of being quantitative can also justify the calibration of other analytical methods. In pharmaceutical domain, quantitative NMR (qNMR) can be applied in the identification and quantification of drug simultaneously. The early drug development stage requires a minimum sample for analysis. Thus, priority should be given to utilize this technique to attain results with least investment, rapid analysis time and minimum sample consumption. This technique is a significant phenomenon to identify impurities, drug substance, residual solvents of in-process control (IPC) samples and characterizing the formulations. From an analyst's perspective, qNMR proved to be a routine practice in pharmaceutical industry to qualify any drug product. The absolute and relative methods offer great help in quantifying the component of interest in the process control samples and finished products. This review highlights the evolution of NMR application in the pharmaceutical industry, where determining the purity of drug substance, drug product and establishing the identity of impurities and its level are the challenging aspects. NMR in medicinal field emerging as a numero uno for Covid-19 severity detection and its dire consequences, accelerated vaccine development and the mapping of SAR-COV-2 RNA and proteins via chemical shift assignments.
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Affiliation(s)
- Adila Khalil
- Analytical Chemistry Section, Department of Chemistry, Aligarh Muslim University, Aligarh, Uttar Pradesh, India
| | - Mohammad Kashif
- Analytical Chemistry Section, Department of Chemistry, Aligarh Muslim University, Aligarh, Uttar Pradesh, India
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El-Masry AA, El-Wasseef DR, Eid M, Shehata IA, Zeid AM. Quantitative proton nuclear magnetic resonance method for simultaneous analysis of fluticasone propionate and azelastine hydrochloride in nasal spray formulation. ROYAL SOCIETY OPEN SCIENCE 2021; 8:210483. [PMID: 34277026 PMCID: PMC8278066 DOI: 10.1098/rsos.210483] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Accepted: 06/10/2021] [Indexed: 06/13/2023]
Abstract
A facile, rapid, accurate and selective quantitative proton nuclear magnetic resonance (1H-qNMR) method was developed for the simultaneous determination of fluticasone propionate (FLP) and azelastine hydrochloride (AZH) in pharmaceutical nasal spray for the first time. The 1H-qNMR analysis of the studied analytes was performed using inositol as the internal standard and dimethyl sulfoxide-d6 (DMSO-d6) as the solvent. The quantitative selective proton signal of FLP was doublet of doublet at 6.290, 6.294, 6.316 and 6.319 ppm, while that of AZH was doublet at 8.292 and 8.310 ppm. The internal standard (inositol) produced a doublet signal at 3.70 and 3.71 ppm. The method was rectilinear over the concentration ranges of 0.25-20.0 and 0.2-15.0 mg ml-1 for FLP and AZH, respectively. No labelling or pretreatment steps were required for NMR analysis of the studied analytes. The proposed 1H-qNMR method was validated efficiently according to the International Council on Harmonisation guidelines in terms of linearity, limit of detection, limit of quantification, accuracy, precision, specificity and stability. Moreover, the method was applied to assay the analytes in their combined nasal spray formulation. The results ensured the linearity (r 2 > 0.999), precision (% RSD < 1.5), stability, specificity and selectivity of the developed method.
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Affiliation(s)
- Amal A. El-Masry
- Department of Medicinal Chemistry, Mansoura University, 35516 Mansoura, Egypt
| | - Dalia R. El-Wasseef
- Department of Medicinal Chemistry, Mansoura University, 35516 Mansoura, Egypt
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Delta University for Science and Technology, 35712 Gamasa, Egypt
| | - Manal Eid
- Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Mansoura University, 35516 Mansoura, Egypt
| | - Ihsan A. Shehata
- Department of Medicinal Chemistry, Mansoura University, 35516 Mansoura, Egypt
| | - Abdallah M. Zeid
- Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Mansoura University, 35516 Mansoura, Egypt
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Morlock GE, Heil J. HI-HPTLC-UV/Vis/FLD-HESI-HRMS and bioprofiling of steviol glycosides, steviol, and isosteviol in Stevia leaves and foods. Anal Bioanal Chem 2020; 412:6431-6448. [PMID: 32328691 PMCID: PMC7442773 DOI: 10.1007/s00216-020-02618-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 03/20/2020] [Accepted: 03/25/2020] [Indexed: 12/13/2022]
Abstract
Food products and botanicals on the global market need to be investigated in a more comprehensive way to detect effects, falsifications or adulterations. This is especially true for such ones containing Stevia leaves, Stevia extracts, or steviol glycosides. A multi-imaging profiling was developed exploiting hydrophilic interaction liquid chromatography (HILIC). A minimalistic sample preparation, different mixtures of acetonitrile and water/buffer on the silica gel phase as well as derivatization reagents and optional hyphenation with high-resolution mass spectrometry were exploited. The hydrophilic interaction high-performance thin-layer chromatography (HI-HPTLC) development took 10 min for 48 analyses. It was used to screen Stevia leaf extracts and 20 different food products. For the first time, the biological and biochemical profiling of Stevia leaf products by HI-HPTLC-UV/Vis/FLD-assay pointed to 19 different bioactive compound bands found in the more natural multicomponent Stevia leaf extracts, whereas most of these activities were not existent for the steviol glycosides. The chemically isolated, purified, and EU-regulated steviol glycosides ease risk assessment and food product development. However, multipotent botanicals may have subtle impact on homeostasis via several metabolic pathways, providing benefits for the consumer's health. Analyzed side by side by means of the effect-directed profiling, their individual activity profiles were visualized as image and individual substances of importance were pointed out. Multi-imaging (comprehensive detection) plus non-targeted bioprofiling (focus on known and unknown bioactivity) allows for a fast detection of questionable product changes that occur along the global food chain and are particularly related to food safety. Graphical abstract.
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Affiliation(s)
- Gertrud E Morlock
- Institute of Nutritional Science, Chair of Food Science, and TransMIT Center for Effect-Directed Analysis, Justus Liebig University Giessen, Heinrich-Buff-Ring 26-32, 35392, Giessen, Germany.
| | - Julia Heil
- Institute of Nutritional Science, Chair of Food Science, and TransMIT Center for Effect-Directed Analysis, Justus Liebig University Giessen, Heinrich-Buff-Ring 26-32, 35392, Giessen, Germany
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Souza ACL, Ramos AS, Mar JM, Boeira LS, de Bezerra JA, Machado MB. Alcoholic beverages from araçá-boi fruit: quantification of antioxidant compounds by NMR ERETIC2. Journal of Food Science and Technology 2020; 57:4733-4738. [PMID: 33087984 DOI: 10.1007/s13197-020-04721-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Revised: 05/26/2020] [Accepted: 08/13/2020] [Indexed: 12/17/2022]
Abstract
Fermentation is a preservation process responsible for increasing food product shelf life. In this context, alcoholic fermentation can add value to unconventional Amazon fruits, e.g., araçá-boi (Eugenia stipitata). This fruit has various antioxidant phenolic compounds with well-known nutraceutical properties. However, araçá-boi is still underexplored by food industry. This rationale led to investigate the influence of five commercial yeasts (Saccharomyces cerevisiae) and filtration process on chemical composition and antioxidant capacity of araçá-boi beverages. DPPH and Folin Ciocalteu assays were used to determine antioxidant capacity and total phenolic content. Organic compounds' contents were assessed by NMR-ERETIC2. In all beverages, ten compounds [tyrosol, sucrose, fructose, (α/β)-glucose, ethanol, malic, citric, gallic, and succinic acids] were identified and quantified. The highest phenolic concentrations [gallic acid (390.0 µM) and tyrosol (380.0 µM)] were found in Biolievito Bayanus (BBA) beverage. The new BBA beverage was used for investigating filtration process influence on chemical composition and antioxidant responses. Alcoholic content (unfiltered: 13.9°GL and filtered: 12.7°GL), antioxidant responses, and total phenolic contents were influenced by filtration process. The yeast type and unfiltered process were determinant for chemical content and antioxidant capacity of beverages. These results might be useful to private sector and future production and commercialization of araçá-boi beverages.
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Affiliation(s)
- Amanda C L Souza
- Núcleo de Estudos Químicos de Micromoléculas da Amazônia - NEQUIMA, Universidade Federal do Amazonas - UFAM, Manaus, Amazonas Brazil
| | - Andrezza S Ramos
- Núcleo de Estudos Químicos de Micromoléculas da Amazônia - NEQUIMA, Universidade Federal do Amazonas - UFAM, Manaus, Amazonas Brazil
| | - Josiana M Mar
- Núcleo de Estudos Químicos de Micromoléculas da Amazônia - NEQUIMA, Universidade Federal do Amazonas - UFAM, Manaus, Amazonas Brazil
| | - Lúcia S Boeira
- Department of Chemistry, Environment and Food, Instituto Federal de Educação, Ciência e Tecnologia do Amazonas - IFAM, Manaus, Amazonas Brazil
| | - Jaqueline A de Bezerra
- Núcleo de Estudos Químicos de Micromoléculas da Amazônia - NEQUIMA, Universidade Federal do Amazonas - UFAM, Manaus, Amazonas Brazil.,Department of Chemistry, Environment and Food, Instituto Federal de Educação, Ciência e Tecnologia do Amazonas - IFAM, Manaus, Amazonas Brazil
| | - Marcos B Machado
- Núcleo de Estudos Químicos de Micromoléculas da Amazônia - NEQUIMA, Universidade Federal do Amazonas - UFAM, Manaus, Amazonas Brazil
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Food Safety Risk Assessment of γ-Butyrolactone Transformation into Dangerous γ-Hydroxybutyric Acid in Beverages by Quantitative 13C-NMR Technique. J FOOD QUALITY 2020. [DOI: 10.1155/2020/8846214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Food safety remains a matter of great concern in most countries and the composition in food is crucial to food safety. It is very important to make sense of the quality and change of food ingredients. In this research, the change of γ-butyrolactone (GBL), one kind of food additive in beverage, had been evaluated by nuclear magnetic resonance (NMR) technique. The 1H-NMR results of seven beverages covering various kinds with spiked GBL indicated that GBL was transformed into dangerous γ-hydroxybutyric acid (GHB) in six popular beverages under certain conditions which could happen during transportation and storage. Further results of quantitative 13C-NMR showed that pH and temperature were two key factors affecting the transforming degree of GBL to GHB. Lower pH and higher temperature will increase the degree of transformation. GHB was a neurotransmitter on the chemical control list, which was absolutely forbidden to be added to food. This nondestructive NMR detecting technology which did not need the complex pretreatment method to directly determine food ingredients can be useful for identifying the risk of food safety from the changes of food composition during transport and storage.
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Nasr JJ, Shalan S. Validated 1H and 19F nuclear magnetic resonance for the quantitative determination of the hepatitis C antiviral drugs sofosbuvir, ledipasvir, and daclatasvir in tablet dosage forms. Microchem J 2020. [DOI: 10.1016/j.microc.2019.104437] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Ma K, Li X, Zhang Y, Liu F. Determining High-Intensity Sweeteners in White Spirits Using an Ultrahigh Performance Liquid Chromatograph with a Photo-Diode Array Detector and Charged Aerosol Detector. Molecules 2019; 25:molecules25010040. [PMID: 31861939 PMCID: PMC6983009 DOI: 10.3390/molecules25010040] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 12/13/2019] [Accepted: 12/14/2019] [Indexed: 12/03/2022] Open
Abstract
In China, white spirit is not only an alcoholic drink but also a cultural symbol. A novel and accurate method for simultaneously determining nine sweeteners (most authorized for use in China) in white spirits by ultrahigh performance liquid chromatography (UHPLC) with a photo-diode array detector (PDA) and charged aerosol detector (CAD) was developed. The sweeteners were acesulfame, alitame, aspartame, dulcin, neotame, neohesperidine dihydrochalcone, saccharin, sodium cyclamate, and sucralose. The sweeteners were separated within 16 min using a BEH C18 column and linear gradient-elution program. The optimized method allowed low concentrations (micrograms per gram) of sweeteners to be simultaneously detected. The CAD gave good linearities (correlation coefficients > 0.9936) for all analytes at concentrations of 0.5 to 50.0 μg/g. The limits of detection were 0.16 to 0.77 μg/g. Acesulfame, dulcin, neohesperidine dihydrochalcone, and saccharin were determined using the PDA detector, which gave correlation coefficients > 0.9994 and limits of detection of 0.16 to 0.22 μg/g. The recoveries were 95.1% to 104.9% and the relative standard deviations were 1.6% to 3.8%. The UHPLC-PDA-CAD method is more convenient and cheaper than LC-MS/MS methods. The method was successfully used in a major project called “Special Action against Counterfeit and Shoddy white spirits” and to monitor risks posed by white spirits in China.
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Affiliation(s)
- Kang Ma
- Division of Chemical Metrology and Analytical Science, National Institute for Metrology of China, Beijing 100013, China
- Beijing Key Laboratory of Water Resources and Environmental Engineering, China University of Geosciences (Beijing), Beijing 100083, China
- Correspondence: (K.M.); (F.L.); Tel.: +86-010-64524783 (K.M.); +86-010-82321027 (F.L.); Fax: +86-010-6452478 (K.M.); +86-010-82321081 (F.L.)
| | - Xiaojia Li
- College of Chemistry and Bioengineering, University of Science and Technology Beijing, Beijing 100083, China;
| | - Yiwen Zhang
- Beijing Institute of Metrology, Beijing 100021, China;
| | - Fei Liu
- Beijing Key Laboratory of Water Resources and Environmental Engineering, China University of Geosciences (Beijing), Beijing 100083, China
- Correspondence: (K.M.); (F.L.); Tel.: +86-010-64524783 (K.M.); +86-010-82321027 (F.L.); Fax: +86-010-6452478 (K.M.); +86-010-82321081 (F.L.)
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