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Abdel Hamid M, Habib A, Mabrouk M, Hammad S, Elshahawy M. Formation of plasmonic silver nanoparticles by glucosamine reduction: Application to a colorimetric sensor for determination of glucosamine in its pharmaceutical preparations. J Pharm Biomed Anal 2023; 236:115705. [PMID: 37690186 DOI: 10.1016/j.jpba.2023.115705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 08/18/2023] [Accepted: 09/02/2023] [Indexed: 09/12/2023]
Abstract
The purpose of this study is to develop a novel method for synthesizing silver nanoparticles using glucosamine as reducing agent and to utilize the developed method for colorimetric detection and quantitative determination of the non-chromophoric drug, glucosamine. Silver nanoparticles are prepared by reducing 0.02 mol/L silver nitrate by glucosamine in 0.075 mol/L ammonia and stabilizing the nanoparticles with 0.1% polyvinylpyrrolidone and the mixture is heated at 90 °C for 5 min. The prepared silver nanoparticles dispersed in water exhibit a bright yellow color due to a localized surface plasmon resonance band at 412 nm. The principle of glucosamine sensing is based on measuring the intensity of the surface plasmon resonance band at 412 nm which is directly proportional to the concentration of glucosamine with a linearity range (1 - 9 μg/mL), limit of detection 0.33 μg/mL and limit of quantitation 1.0 μg/mL. The proposed method was validated according to the ICH guidelines, and it was found to be accurate, precise, selective, and robust. The method was applied for determination of glucosamine in Joflex® capsules using the standard addition approach with mean % recovery ± standard deviation of 100.077 ± 1.786. The method is simple, rapid, and cost-effective and can be used for determination of glucosamine in bulk and in its pharmaceutical preparations.
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Affiliation(s)
- Mohamed Abdel Hamid
- Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Tanta University, Tanta, Egypt
| | - Ahmed Habib
- Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Tanta University, Tanta, Egypt
| | - Mokhtar Mabrouk
- Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Tanta University, Tanta, Egypt
| | - Sherin Hammad
- Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Tanta University, Tanta, Egypt
| | - Mahmoud Elshahawy
- Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Tanta University, Tanta, Egypt.
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Kvasnička F, Kouřimská L, Bleha R, Škvorová P, Kulma M, Rajchl A. ELECTROPHORETIC DETERMINATION OF CHITIN IN INSECTS. J Chromatogr A 2023; 1695:463952. [PMID: 37011523 DOI: 10.1016/j.chroma.2023.463952] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 03/22/2023] [Accepted: 03/25/2023] [Indexed: 03/30/2023]
Abstract
An electrophoretic method (on-line coupled capillary isotachophoresis with capillary zone electrophoresis with conductometric detection (cITP-CZE-COND)) for the determination of chitin in insects based on the analysis of glucosamine after acidic hydrolysis of the sample is described. Chitin is deacetylated and hydrolyzed to glucosamine by acidic hydrolysis (6 M sulfuric acid, 110 °C, 6 h). Under optimized electrophoresis conditions, glucosamine (GlcN) is separated from other sample components in cationic mode and detected with a conductometer within 15 min. The performance method characteristics of the GlcN assay, i.e., linearity (0.2-20 μmol), accuracy (103 ± 5%), repeatability (1.9%), reproducibility (3.4%), limits of detection (0.06 μmol/L) and quantification (0.2 μmol/L), were evaluated. On a series of 28 insect samples, it was proven that cITP-CZE-COND provides results of chitin content in insects comparable to the literature data. The important features of the developed cITP-CZE-COND method are easy sample treatment, high sensitivity and selectivity, and low running costs. It is clear from the above that the cITP-CZE-COND method is suitable for analysis of insect samples for chitin content.
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Affiliation(s)
- František Kvasnička
- Department of Food Preservation, University of Chemistry and Technology Prague, Technická 3, 166 28 Prague 6, Czech Republic.
| | - Lenka Kouřimská
- Department of Microbiology, Nutrition and Dietetics, Czech University of Life Sciences Prague, Kamýcká 129, 165 00 Praha-Suchdol, Czech Republic
| | - Roman Bleha
- Department of Carbohydrates and Cereals, University of Chemistry and Technology Prague, Technická 3, 166 28 Prague 6, Czech Republic
| | - Petra Škvorová
- Department of Microbiology, Nutrition and Dietetics, Czech University of Life Sciences Prague, Kamýcká 129, 165 00 Praha-Suchdol, Czech Republic
| | - Martin Kulma
- Department of Zoology and Fisheries, Czech University of Life Sciences Prague, Kamýcká 129, 165 00 Praha-Suchdol, Czech Republic
| | - Aleš Rajchl
- Department of Food Preservation, University of Chemistry and Technology Prague, Technická 3, 166 28 Prague 6, Czech Republic
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Nguyen QH, Dang THM, Quynh Le TP, Luu THT, Dinh TD, Mai TK, Nguyen TMT, Nguyen TAH, Mai TD. Inexpensive and simple tool for quality control of nutraceutical and tonic products with capillary electrophoresis and contactless conductivity detection: Some developments in Vietnam. J Food Compost Anal 2023. [DOI: 10.1016/j.jfca.2022.104882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Development of a Quantitative UPLC-ESI/MS Method for the Simultaneous Determination of the Chitin and Protein Content in Insects. FOOD ANAL METHOD 2022. [DOI: 10.1007/s12161-022-02411-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Abstract
In a context where the commercial and nutritional interest in insect chitin is always increasing, an accurate and precise method to quantify this biopolymer, especially in food/feed, is required. In addition, quantification of insect crude protein through nitrogen determination is normally overestimated due to the presence of chitin. In this work, for the first time, an RP-UPLC-ESI/MS method for the simultaneous quantification in insects of chitin, as glucosamine (GlcN), and protein, as total amino acids, is presented. The method is based on acid hydrolysis and derivatization of amino acids and GlcN with the AccQ Tag reagent. Method was optimized and validated in terms of linearity, LOD and LOQ, intraday and inter-day repeatability, and accuracy. A hydrolysed commercial chitin was selected as reference standard for calibration. The instrumental LOD and LOQ correspond respectively to a concentration of 0.00068 mM and 0.00204 mM. The intraday precision satisfied the Horwitz ratio. Data from inter-day precision showed the necessity to perform the analysis within 1 week utilizing standard calibration solutions freshly prepared. A matrix effect was observed, which suggested the necessity to use an internal calibration curve or to work in a particular concentration range of GlcN. The chitin and protein content in black soldier fly (Hermetia illucens) and lesser mealworm (Alphitobius diaperinus) were found in agreement with results obtained by independent methods. The optimized method was also tested on two different commercial food supplements, suggesting its applicability on a wide range of matrices. This newly developed method proved to be simple, more accurate, and faster if compared to methods which separately analyse chitin and protein content.
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Huyen My Dang T, Quoc Hoang A, Huy Nguyen Q, Chi Le D, Duc Mai T, Nhi Do Y, Anh Kieu V, Khanh Cao C, Minh Hien Lu T, Minh Thu Nguyen T, Pham B, Anh Huong Nguyen T. Simultaneous determination of vitamin B 6 and magnesium using capillary electrophoresis coupled with contactless conductivity detection: Method development, validation, and application to pharmaceutical and nutraceutical samples. J Chromatogr B Analyt Technol Biomed Life Sci 2022; 1210:123471. [PMID: 36174264 DOI: 10.1016/j.jchromb.2022.123471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Revised: 09/09/2022] [Accepted: 09/13/2022] [Indexed: 11/29/2022]
Abstract
Vitamins and minerals are usually incorporated in pharmaceutical and nutraceutical products, but a simple, rapid, and inexpensive analytical method for their simultaneous determination is still lacking. In this study, we developed a quantification method for pyridoxine (vitamin B6) and magnesium (Mg) by using purpose-made capillary electrophoresis with capacitively coupled contactless conductivity detection (CE-C4D) instrument. Main analytical conditions include: fused silica capillary (total length 55 cm, effective length 40 cm, inner diameter 50 μm); background electrolyte consisted of 10 mM L-arginine/acetic acid (pH 5) with 20% acetonitrile; separation voltage + 20 kV; hydrodynamic injection (siphoning at 20 cm in 25 s). Detection limits of vitamin B6 and Mg were 1 and 0.1 mg/L, respectively. Good linearity (R2 > 0.999) was observed for vitamin B6 and Mg calibration curves over concentration ranges of 3-100 and 0.3-200 mg/L, respectively. The method was applied to analyze vitamin B6 and Mg in several pharmaceutical and nutraceutical samples. The analytical results obtained by our method were in good agreement with reference methods (i.e., HPLC for vitamin B6 and ICP-OES for Mg). High-efficient and low-cost CE-C4D method can accordingly serve as a promising tool for concurrent analysis of inorganic and organic species in pharmaceutical and nutraceutical analysis.
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Affiliation(s)
- Thi Huyen My Dang
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19, Le Thanh Tong, Hanoi 10000, Vietnam
| | - Anh Quoc Hoang
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19, Le Thanh Tong, Hanoi 10000, Vietnam.
| | - Quang Huy Nguyen
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19, Le Thanh Tong, Hanoi 10000, Vietnam; Faculty of Pharmacy, University of Medicine and Pharmacy, Thai Nguyen University, 284, Luong Ngoc Quyen, Thai Nguyen 24000, Vietnam
| | - Dinh Chi Le
- Department of Analytical Chemistry and Toxicology, Hanoi University of Pharmacy, 13-15 Le Thanh Tong, Hanoi 10000, Vietnam
| | - Thanh Duc Mai
- Université Paris-Saclay, CNRS, Institut Galien Paris-Saclay, 92296, Châtenay-Malabry, France
| | - Yen Nhi Do
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19, Le Thanh Tong, Hanoi 10000, Vietnam
| | - Van Anh Kieu
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19, Le Thanh Tong, Hanoi 10000, Vietnam
| | - Cong Khanh Cao
- National Institute for Food Control (NIFC), 65, Pham Than Duat, Hanoi 10000, Vietnam
| | - Thi Minh Hien Lu
- National Institute for Food Control (NIFC), 65, Pham Than Duat, Hanoi 10000, Vietnam
| | - Thi Minh Thu Nguyen
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19, Le Thanh Tong, Hanoi 10000, Vietnam
| | - Bach Pham
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19, Le Thanh Tong, Hanoi 10000, Vietnam
| | - Thi Anh Huong Nguyen
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19, Le Thanh Tong, Hanoi 10000, Vietnam.
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Capillary and microchip electrophoresis with contactless conductivity detection for analysis of foodstuffs and beverages. Food Chem 2021; 375:131858. [PMID: 34923397 DOI: 10.1016/j.foodchem.2021.131858] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 11/29/2021] [Accepted: 12/10/2021] [Indexed: 12/17/2022]
Abstract
The paper provides a comprehensive survey of the use of capillary and microchip electrophoresis in combination with contactless conductivity detection (C4D) for the analysis of drinking water, beverages and foodstuffs. The introduction sets forth the fundamentals of conductivity detection anddescribes an axialC4Dversion. There is also a detailed discussion of the determination of inorganic ions, organic acids, fatty acids, amino acids, amines, carbohydrates, foreign substances and poisons from the standpoint of separation conditions, sample treatment and detection limits. Special attention is paid to the analysis of foodstuffs at microchips with emphasis on the employed material and connection of the microchip with the C4D. The review attempts to draw attention to modern trends, such as dual-opposite injection, field-enhanced sample injection, electromembrane extraction and on-line combination of microdialysis with CE. CE/C4D is characterised by high universality, high speed of analysis, simple sample preparation, small consumption of sample and other chemicals.
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Rocco A, Donati E, Touloupakis E, Aturki Z. Miniaturized separation techniques as analytical methods to ensure quality and safety of dietary supplements. Trends Analyt Chem 2018. [DOI: 10.1016/j.trac.2018.04.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Sanches-Silva A, Ribeiro T, Albuquerque TG, Paseiro P, Sendón R, de Quirós AB, López-Cervantes J, Sánchez-Machado DI, Valdez HS, Angulo I, Aurrekoetxea GP, Costa HS. Ultra-high pressure LC determination of glucosamine in shrimp by-products and migration tests of chitosan films. J Sep Sci 2012; 35:633-40. [PMID: 22517638 DOI: 10.1002/jssc.201100855] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Chitosan, a multiple applications molecule, was isolated from shrimp by-products by fermentation. The amount of chitosan in the solid fraction of the fermented extract was measured after its conversion in the respective glucosamine units. The procedure includes an acid hydrolysis (110 °C, 4 h with HCl 8 M) and a derivatization with 9-fluorenylmethyl chloroformate (Fmoc-Cl). Ultra-high-pressure liquid chromatography method was developed and optimized. Excellent peaks resolution was achieved in just 10 min. The method was evaluated in what concerns to validation parameters such as linearity, repeatability, quantification limit, and recovery. Migration tests of films prepared with chitosan were carried out in two simulants: ultrapure water and ethanol 95% (v/v).
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Affiliation(s)
- Ana Sanches-Silva
- Food and Nutrition Department, National Institute of Health Dr Ricardo Jorge, Lisbon, Portugal.
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Abstract
AbstractCapillary electrophoresis (CE) is an attractive technique in separation science because of its high separation performance, short analysis time and low cost. Electrochemical detection (EC) is a powerful tool for CE because of its high sensitivity. In this review, developments of CE-EC from 2008 to August, 2011 are reviewed. We choose papers of innovative and novel results to demonstrate the newest and most important progress in CE-EC.
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Akamatsu S, Mitsuhashi T. Development of a simple capillary electrophoretic determination of glucosamine in nutritional supplements using in-capillary derivatisation with o-phthalaldehyde. Food Chem 2012. [DOI: 10.1016/j.foodchem.2011.08.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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11
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Jin P, Yan X, Wang Z, Wu X, Zou D, Hu X, Sun C. DEVELOPMENT, COMPARISON, AND PEAK VALIDATION OF A HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY METHOD FOR DIRECT DETERMINATION OF GLUCOSAMINE HYDROCHLORIDE IN PHARMACEUTICAL FORMULATIONS. J LIQ CHROMATOGR R T 2011. [DOI: 10.1080/10826076.2011.591032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Affiliation(s)
- Pengfei Jin
- a Department of Pharmaceutical Science , Beijing Hospital , Beijing , China
| | - Xiaoyan Yan
- a Department of Pharmaceutical Science , Beijing Hospital , Beijing , China
| | - Zhihong Wang
- a Department of Pharmaceutical Science , Beijing Hospital , Beijing , China
| | - Xuejun Wu
- a Department of Pharmaceutical Science , Beijing Hospital , Beijing , China
| | - Ding Zou
- a Department of Pharmaceutical Science , Beijing Hospital , Beijing , China
| | - Xin Hu
- a Department of Pharmaceutical Science , Beijing Hospital , Beijing , China
| | - Chunhua Sun
- a Department of Pharmaceutical Science , Beijing Hospital , Beijing , China
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Song M, Hang TJ, Wang C, Yang L, Wen AD. Precolumn derivatization LC-MS/MS method for the determination and pharmacokinetic study of glucosamine in human plasma and urine. J Pharm Anal 2011; 2:19-28. [PMID: 29403716 PMCID: PMC5760825 DOI: 10.1016/j.jpha.2011.08.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Accepted: 08/30/2011] [Indexed: 10/28/2022] Open
Abstract
A selective precolumn derivatization liquid chromatography-tandem mass spectrometric (LC-MS/MS) method for the determination of glucosamine in human plasma and urine has been developed and validated. Glucosamine was derivatized by o-phthalaldehyde/3-mercaptopropionic acid. Chromatographic separation was performed on a Phenomenex ODS column (150 mm×4.6 mm, 5 μm) using linear gradient elution by a mobile phase consisting of methanol (A), and an aqueous solution containing 0.2% ammonium acetate and 0.1% formic acid (B) at a flow rate of 1 mL/min. Tolterodine tartrate was used as the internal standard (IS). With protein precipitation by acetonitrile and then the simple one-step derivatization, a sensitive bio-assay was achieved with the lower limit of quantitation (LLOQ) as low as 12 ng/mL for plasma. The standard addition calibration curves suitable for clinical sample analysis showed good linearity over the range of 0.012-8.27 μg/mL in plasma and 1.80-84.1 μg/mL in urine. The fully validated method has been successfully applied to a pharmacokinetic study of compound glucosamine sulfate dispersible tablets in health Chinese volunteers receiving single oral doses at 500, 1000 and 1500 mg of glucosamine sulfate, as well as multiple oral doses of 500 mg t.i.d. for 7 consecutive days.
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Affiliation(s)
- Min Song
- Department of Pharmaceutical Analysis, China Pharmaceutical University, Nanjing 210009, China
| | - Tai-Jun Hang
- Department of Pharmaceutical Analysis, China Pharmaceutical University, Nanjing 210009, China
| | - Cheng Wang
- Department of Pharmaceutical Analysis, China Pharmaceutical University, Nanjing 210009, China
| | - Lin Yang
- Department of Pharmacy, Xijing Hospital, Xi'an 710032, China
| | - Ai-Dong Wen
- Department of Pharmacy, Xijing Hospital, Xi'an 710032, China
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Chaisuwan P, Kongprasertsak T, Sangcakul A, Smith NW, Nachapricha D, Wilairat P, Uraisin K. Direct injection of human serum and pharmaceutical formulations for glucosamine determination by CE-C4D method. J Chromatogr B Analyt Technol Biomed Life Sci 2011; 879:2185-8. [DOI: 10.1016/j.jchromb.2011.05.045] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2011] [Revised: 05/25/2011] [Accepted: 05/31/2011] [Indexed: 11/24/2022]
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Petrů K, Jáč P, Lužová V, Kuneš J, Polášek M. Determination of muscle relaxants pancuronium and vecuronium bromide by capillary electrophoresis with capacitively coupled contactless conductivity detection. Electrophoresis 2011; 32:890-5. [DOI: 10.1002/elps.201000456] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2010] [Revised: 10/04/2010] [Accepted: 10/04/2010] [Indexed: 11/10/2022]
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Kubáň P, Hauser PC. Capacitively coupled contactless conductivity detection for microseparation techniques - recent developments. Electrophoresis 2010; 32:30-42. [DOI: 10.1002/elps.201000354] [Citation(s) in RCA: 121] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2010] [Revised: 08/12/2010] [Accepted: 08/13/2010] [Indexed: 11/09/2022]
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Recent advances of capillary electrophoresis in pharmaceutical analysis. Anal Bioanal Chem 2010; 398:29-52. [DOI: 10.1007/s00216-010-3741-5] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2010] [Revised: 04/08/2010] [Accepted: 04/09/2010] [Indexed: 01/16/2023]
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Volpi N. Capillary electrophoresis determination of glucosamine in nutraceutical formulations after labeling with anthranilic acid and UV detection. J Pharm Biomed Anal 2009; 49:868-71. [PMID: 19200685 DOI: 10.1016/j.jpba.2009.01.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2008] [Revised: 01/08/2009] [Accepted: 01/08/2009] [Indexed: 10/21/2022]
Abstract
A new robust CE method for the determination of the glucosamine (GlcN) content in nutraceutical formulations is described after its derivatization with anthranilic acid (2-aminobenzoic acid, AA). The CE separation of derivatized GlcN with AA was performed on an uncoated fused-silica capillary tube (50 microm I.D.) using an operating pH 7.0 buffer of 150 mM boric acid/50 mM NaH2PO4 and UV detection at 214 nm. The method was validated for specificity, linearity, accuracy, precision, limit of detection (LOD), and limit of quantitation (LOQ). The detector response for GlcN was linear over the selected concentration range from 240 to 2400 pg (40-400 microg/mL) with a correlation coefficient greater than 0.980. The intra- and inter-day variations (CV%) were between 0.5 and 0.9 for migration time, and between 2.8 and 4.3 for peak area, respectively. The LOD and the LOQ of the method were approximately 200 and 500 pg, respectively. The intra- and inter-day accuracy was estimated to range from 2.8% to 5.1%, while the percent recoveries of GlcN in formulations were calculated to be about 100% after simple centrifugation for 10 min, lyophilization and derivatization with AA. The CE method was applied to the determination of GlcN content, in the form of GlcN-hydrochloride or GlcN-sulfate, of several nutraceutical preparations in the presence of other ingredients, i.e. chondroitin sulfate, vitamin C and/or methylsulfonylmethane (MSM) as well as salts and other agents. The quantitative results obtained were in total conformity with the label claims.
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Affiliation(s)
- Nicola Volpi
- Department of Biologia Animale, University of Modena and Reggio Emilia, Via Campi 213/d, 41100 Modena, Italy.
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