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Yu S, You J, Shi X, Zou X, Lu Z, Wang Y, Tan J, Sun Z, Li Z, Ji Z, Song C. Rapid Analysis of Estrogens in Meat Samples by High Performance Liquid Chromatography with Fluorescence Detection. J Fluoresc 2024; 34:425-436. [PMID: 37284963 DOI: 10.1007/s10895-023-03248-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Accepted: 04/18/2023] [Indexed: 06/08/2023]
Abstract
A novel reagent named 4-(N-methyl-1,3-dioxo-benzoisoquinolin-6-yl-oxy)benzene sulfonyl chloride (MBIOBS-Cl) for the determination of estrogens in food samples by high-performance liquid chromatography (HPLC) with fluorescence detection has been developed. Estrogens could be easily labeled by MBIOBS-Cl in Na2CO3-NaHCO3 buffer solution at pH 10.0. The complete labeling reaction for estrogens could be accomplished within five minutes, the corresponding derivatives exhibited strong fluorescence with the maximum excitation and emission wavelengths at 249 nm and 443 nm, respectively. The derivatization conditions, such as the molar ratio of reagent to estrogens, derivatization time, pH, temperature, and buffers were optimized. Derivatives were sufficiently stable to be efficiently analyzed by HPLC with a reversed-phase Agilent ZORBAX 300SB-C18 column with a good baseline resolution. Excellent linear correlations were obtained for all estrogen derivatives with correlation coefficients greater than 0.9998. Ultrasonic-Assisted extraction was used to optimize the extraction of estrogens from meat samples with a recovery higher than 82%. The detection limits (LOD, S/N = 3) of the method ranged from 0.95 to 3.3 μg· kg-1. The established method, which is fast, simple, inexpensive, and environment friendly, can be successfully applied for the detection of four steroidal estrogens from meat samples with little matrix interference.
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Affiliation(s)
- Shuiqiang Yu
- Key Laboratory of Life-Organic Analysis of Shandong Province, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, 273165, People's Republic of China
| | - Jinmao You
- Key Laboratory of Life-Organic Analysis of Shandong Province, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, 273165, People's Republic of China.
- College of Chemistry and Chemical Engineering, Shaoxing University, Shaoxing, 312000, People's Republic of China.
| | - Xinxin Shi
- Key Laboratory of Life-Organic Analysis of Shandong Province, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, 273165, People's Republic of China
| | - Xiaocong Zou
- Key Laboratory of Life-Organic Analysis of Shandong Province, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, 273165, People's Republic of China
| | - Zhihao Lu
- Key Laboratory of Life-Organic Analysis of Shandong Province, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, 273165, People's Republic of China
| | - Yu Wang
- Key Laboratory of Life-Organic Analysis of Shandong Province, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, 273165, People's Republic of China
| | - Jiangkun Tan
- Key Laboratory of Life-Organic Analysis of Shandong Province, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, 273165, People's Republic of China
| | - Zhiwei Sun
- Key Laboratory of Life-Organic Analysis of Shandong Province, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, 273165, People's Republic of China
| | - Zan Li
- Key Laboratory of Life-Organic Analysis of Shandong Province, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, 273165, People's Republic of China
| | - Zhongyin Ji
- Key Laboratory of Life-Organic Analysis of Shandong Province, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, 273165, People's Republic of China
| | - Cuihua Song
- Key Laboratory of Life-Organic Analysis of Shandong Province, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, 273165, People's Republic of China
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Kaleta M, Oklestkova J, Novák O, Strnad M. Analytical Methods for the Determination of Neuroactive Steroids. Biomolecules 2021; 11:553. [PMID: 33918915 PMCID: PMC8068886 DOI: 10.3390/biom11040553] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 04/01/2021] [Accepted: 04/08/2021] [Indexed: 12/27/2022] Open
Abstract
Neuroactive steroids are a family of all steroid-based compounds, of both natural and synthetic origin, which can affect the nervous system functions. Their biosynthesis occurs directly in the nervous system (so-called neurosteroids) or in peripheral endocrine tissues (hormonal steroids). Steroid hormone levels may fluctuate due to physiological changes during life and various pathological conditions affecting individuals. A deeper understanding of neuroactive steroids' production, in addition to reliable monitoring of their levels in various biological matrices, may be useful in the prevention, diagnosis, monitoring, and treatment of some neurodegenerative and psychiatric diseases. The aim of this review is to highlight the most relevant methods currently available for analysis of neuroactive steroids, with an emphasis on immunoanalytical methods and gas, or liquid chromatography combined with mass spectrometry.
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Affiliation(s)
| | - Jana Oklestkova
- Laboratory of Growth Regulators, Faculty of Science and Institute of Experimental Botany of the Czech Academy of Sciences, Palacký University, Šlechtitelů 27, CZ-78371 Olomouc, Czech Republic; (M.K.); (O.N.); (M.S.)
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Lehner A, Johnson M, Zimmerman A, Zyskowski J, Buchweitz J. Vitamin D analyses in veterinary feeds by gas chromatography-tandem mass spectrometry. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2021; 27:48-62. [PMID: 33722092 DOI: 10.1177/14690667211000244] [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: 06/12/2023]
Abstract
This report examines the feasibility of determination of Vitamin D3, D2 and their 25-hydroxy metabolites utilizing Gas Chromatography Tandem Mass Spectrometry (GC/MS/MS) as a potential alternative to popular Liquid Chromatography Tandem Mass Spectrometric (LC/MS/MS) methodologies. The GC/MS/MS approach was found to operate reasonably well despite long-standing concerns that gas-liquid chromatography of vitamin D compounds invoke thermal rearrangements owing to the relatively high inlet and capillary column temperatures used. The workup procedure involved incubation of feed samples with concentrated potassium hydroxide for overnight fat saponification, extraction of D Vitamins in n-hexane and reaction with N,O-bis(trimethylsilyl)trifluoroacetamide at 70 °C for 30 mins. In addition to parent compounds, small amounts of pyro-, isopyro-, and iso-vitamin D and isotachysterol3 variants were obtained from each Vitamin D-related compound upon extraction and GC/MS/MS analysis. Mass spectral and chromatographic behavior of these compounds are herein described and interpreted. Multiple Reaction Monitoring settings on GC/MS/MS included m/z 456→351 for Vitamin D3 and m/z 486→363 for Vitamin D2. Trimethylsilylation enabled single predominant peaks for Vitamins D3 and D2, and sample workup in the presence of deuterated Vitamin D analogs enabled accurate and precise sensitivity to 1 ppb (ng/g) in feeds. The method could be extended with reasonable accuracy to 25-hydroxy (25OH) compounds, but accuracies would be significantly improved by inclusion of respective 25OH-specific deuterated internal standards. The method was applied to 27 submissions of suspect dog foods of which 22% were discovered elevated and 44% were discovered to contain toxic levels of Vitamin D3. The described method was thus discovered to provide a suitable mass spectrometric approach for Vitamin D, proving itself here specifically of value in detection of ergocalciferol and cholecalciferol in animal feeds. The specificity and sensitivity of the tandem quadrupole approach can enable suitable applicability to serum determination if desired.
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Affiliation(s)
- Andreas Lehner
- Michigan State University Veterinary Diagnostic Laboratory, Toxicology Section, Michigan State University, East Lansing, MI, USA
| | - Margaret Johnson
- Michigan State University Veterinary Diagnostic Laboratory, Toxicology Section, Michigan State University, East Lansing, MI, USA
| | - Alan Zimmerman
- Michigan State University Veterinary Diagnostic Laboratory, Toxicology Section, Michigan State University, East Lansing, MI, USA
| | - Justin Zyskowski
- Michigan State University Veterinary Diagnostic Laboratory, Toxicology Section, Michigan State University, East Lansing, MI, USA
| | - John Buchweitz
- Michigan State University Veterinary Diagnostic Laboratory, Toxicology Section, Michigan State University, East Lansing, MI, USA
- Department of Pathobiology & Diagnostic Investigation, Michigan State University College of Veterinary Medicine, Michigan State University, East Lansing, MI, USA
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Conklin SE, Knezevic CE. Advancements in the gold standard: Measuring steroid sex hormones by mass spectrometry. Clin Biochem 2020; 82:21-32. [PMID: 32209333 DOI: 10.1016/j.clinbiochem.2020.03.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 03/16/2020] [Accepted: 03/16/2020] [Indexed: 12/12/2022]
Abstract
Sex hormones, such as testosterone and estrogens, play an essential role in regulating physiological and reproductive development throughout the lifetime of the individual. Although variation in levels of these hormones are observed throughout the distinct stages in life, significant deviations from reference ranges can result in detrimental effects to the individual. Alterations, by either an increase or decrease, in hormone levels are associated with physiological changes, decreased reproductive capabilities, and increased risk for diseases. Hormone therapies (HTs) and assisted reproductive technologies (ARTs) are commonly used to address these factors. In addition to these treatments, gender-affirming therapies, an iteration of HTs, are also a prominent treatment for transgender individuals. Considering that the effectiveness of these treatments relies on achieving therapeutic hormone levels, monitoring of hormones has served as a way of assessing therapeutic efficay. The need for reliable methods to achieve this task has led to great advancements in methods for evaluating hormone concentrations in biological matrices. Although immunoassays are the more widely used method, mass spectrometry (MS)-based methods have proven to be more sensitive, specific, and reliable. Advances in MS technology and its applications for therapeutic hormone monitoring have been significant, hence integration of these methods in the clinical setting is desired. Here, we provide a general overview of HT and ART, and the immunoassay and MS-based methods currently utilized for monitoring sex hormones. Additionally, we highlight recent advances in MS-based methods and discuss future applications and considerations for MS-based hormone assays.
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Affiliation(s)
- Steven E Conklin
- Department of Pathology, The Johns Hopkins University School of Medicine, 1800 Orleans St. Zayed B1020, Baltimore, MD 21287, USA.
| | - Claire E Knezevic
- Department of Pathology, The Johns Hopkins University School of Medicine, 1800 Orleans St. Zayed B1020, Baltimore, MD 21287, USA.
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Denver N, Khan S, Homer NZM, MacLean MR, Andrew R. Current strategies for quantification of estrogens in clinical research. J Steroid Biochem Mol Biol 2019; 192:105373. [PMID: 31112747 PMCID: PMC6726893 DOI: 10.1016/j.jsbmb.2019.04.022] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 04/24/2019] [Accepted: 04/29/2019] [Indexed: 12/22/2022]
Abstract
Estrogens and their bioactive metabolites play key roles in regulating diverse processes in health and disease. In particular, estrogens and estrogenic metabolites have shown both protective and non-protective effects on disease pathobiology, implicating the importance of this steroid pathway in disease diagnostics and monitoring. All estrogens circulate in a wide range of concentrations, which in some patient cohorts can be extremely low. However, elevated levels of estradiol are reported in disease. For example, in pulmonary arterial hypertension (PAH) elevated levels have been reported in men and postmenopausal women. Conventional immunoassay techniques have come under scrutiny, with their selectivity, accuracy and precision coming into question. Analytical methodologies such as gas and liquid chromatography coupled to single and tandem mass spectrometric approaches (GC-MS, GC-MS/MS, LC-MS and LC-MS/MS) have been developed to quantify endogenous estrogens and in some cases their bioactive metabolites in biological fluids such as urine, serum, plasma and saliva. Liquid-liquid or solid-phase extraction approaches are favoured with derivatization remaining a necessity for detection in lower volumes of sample. The limits of quantitation of individual assays vary but are commonly in the range of 0.5-5 pg/mL for estrone and estradiol, with limits for their bioactive metabolites being higher. This review provides an overview of current approaches for measurement of unconjugated estrogens in biological matrices by MS, highlighting the advances in this field and the challenges remaining for routine use in the clinical and research environment.
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Affiliation(s)
- Nina Denver
- Mass Spectrometry Core, Edinburgh Clinical Research Facility, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh, EH16 4TJ, United Kingdom; Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, University Avenue, Glasgow, G12 8QQ, United Kingdom; Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral Street, Glasgow, G4 0RE, United Kingdom.
| | - Shazia Khan
- Mass Spectrometry Core, Edinburgh Clinical Research Facility, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh, EH16 4TJ, United Kingdom; University/BHF Centre for Cardiovascular Science, Queen's Medical Research Institute, University of Edinburgh, 47, Little France Crescent, Edinburgh, UK, EH16 4TJ.
| | - Natalie Z M Homer
- Mass Spectrometry Core, Edinburgh Clinical Research Facility, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh, EH16 4TJ, United Kingdom.
| | - Margaret R MacLean
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral Street, Glasgow, G4 0RE, United Kingdom.
| | - Ruth Andrew
- Mass Spectrometry Core, Edinburgh Clinical Research Facility, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh, EH16 4TJ, United Kingdom; University/BHF Centre for Cardiovascular Science, Queen's Medical Research Institute, University of Edinburgh, 47, Little France Crescent, Edinburgh, UK, EH16 4TJ.
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Mbomson IG, Tabor S, Lahiri B, Sharp G, McMeekin SG, De La Rue RM, Johnson NP. Asymmetric split H-shape nanoantennas for molecular sensing. BIOMEDICAL OPTICS EXPRESS 2017; 8:395-406. [PMID: 28101426 PMCID: PMC5231308 DOI: 10.1364/boe.8.000395] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 12/14/2016] [Accepted: 12/14/2016] [Indexed: 05/20/2023]
Abstract
In this paper we report on a very sensitive biosensor based on gold asymmetric nanoantennas that are capable of enhancing the molecular resonances of C-H bonds. The nanoantennas are arranged as arrays of asymmetric-split H-shape (ASH) structures, tuned to produce plasmonic resonances with reflectance double peaks within the mid-infrared vibrational resonances of C-H bonds for the assay of deposited films of the molecule 17β-estradiol (E2), used as an analyte. Measurements and numerical simulations of the reflectance spectra have enabled an estimated enhancement factor on the order of 105 to be obtained for a thin film of E2 on the ASH array. A high sensitivity value of 2335 nm/RIU was achieved, together with a figure of merit of approximately 8. Our experimental results were corroborated using numerical simulations for the C-H stretch vibrational resonances from the analyte, superimposed on the plasmonic resonances of the ASH nanoantennas.
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Affiliation(s)
- I. G. Mbomson
- School of Engineering, University of Glasgow, Glasgow, G12 8LT, UK
| | - S. Tabor
- School of Engineering, University of Glasgow, Glasgow, G12 8LT, UK
| | - B. Lahiri
- School of Engineering, University of Glasgow, Glasgow, G12 8LT, UK
| | - G. Sharp
- School of Engineering, University of Glasgow, Glasgow, G12 8LT, UK
| | - S. G. McMeekin
- School of Computing and Engineering, Glasgow Caledonian University, Glasgow, G4 0BA, UK
| | - R. M. De La Rue
- School of Engineering, University of Glasgow, Glasgow, G12 8LT, UK
| | - N. P. Johnson
- School of Engineering, University of Glasgow, Glasgow, G12 8LT, UK
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Tseng TTC, Gusviputri A, Hoa LNQ. A simple, sensitive and compact electrochemical ELISA for estradiol based on chitosan deposited platinum wire microelectrodes. J Electroanal Chem (Lausanne) 2015. [DOI: 10.1016/j.jelechem.2015.10.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Liu M, Ingle JN, Fridley BL, Buzdar AU, Robson ME, Kubo M, Wang L, Batzler A, Jenkins GD, Pietrzak TL, Carlson EE, Goetz MP, Northfelt DW, Perez EA, Williard CV, Schaid DJ, Nakamura Y, Weinshilboum RM. TSPYL5 SNPs: association with plasma estradiol concentrations and aromatase expression. Mol Endocrinol 2013; 27:657-70. [PMID: 23518928 DOI: 10.1210/me.2012-1397] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
We performed a discovery genome-wide association study to identify genetic factors associated with variation in plasma estradiol (E2) concentrations using DNA from 772 postmenopausal women with estrogen receptor (ER)-positive breast cancer prior to the initiation of aromatase inhibitor therapy. Association analyses showed that the single nucleotide polymorphisms (SNP) (rs1864729) with the lowest P value (P = 3.49E-08), mapped to chromosome 8 near TSPYL5. We also identified 17 imputed SNPs in or near TSPYL5 with P values < 5E-08, one of which, rs2583506, created a functional estrogen response element. We then used a panel of lymphoblastoid cell lines (LCLs) stably transfected with ERα with known genome-wide SNP genotypes to demonstrate that TSPYL5 expression increased after E2 exposure of cells heterozygous for variant TSPYL5 SNP genotypes, but not in those homozygous for wild-type alleles. TSPYL5 knockdown decreased, and overexpression increased aromatase (CYP19A1) expression in MCF-7 cells, LCLs, and adipocytes through the skin/adipose (I.4) promoter. Chromatin immunoprecipitation assay showed that TSPYL5 bound to the CYP19A1 I.4 promoter. A putative TSPYL5 binding motif was identified in 43 genes, and TSPYL5 appeared to function as a transcription factor for most of those genes. In summary, genome-wide significant SNPs in TSPYL5 were associated with elevated plasma E2 in postmenopausal breast cancer patients. SNP rs2583506 created a functional estrogen response element, and LCLs with variant SNP genotypes displayed increased E2-dependent TSPYL5 expression. TSPYL5 induced CYP19A1 expression and that of many other genes. These studies have revealed a novel mechanism for regulating aromatase expression and plasma E2 concentrations in postmenopausal women with ER(+) breast cancer.
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Affiliation(s)
- Mohan Liu
- Division of Clinical Pharmacology, Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota 55905, USA
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Szarka S, Nguyen V, Prokai L, Prokai-Tatrai K. Separation of dansylated 17β-estradiol, 17α-estradiol, and estrone on a single HPLC column for simultaneous quantitation by LC-MS/MS. Anal Bioanal Chem 2013; 405:3399-406. [PMID: 23371528 DOI: 10.1007/s00216-013-6710-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Revised: 12/16/2012] [Accepted: 01/09/2013] [Indexed: 02/05/2023]
Abstract
We show here that baseline separation of dansylated estrone, 17β-estradiol, and 17α-estradiol can be done, contrary to previous reports, within a short run time on a single RP-LC analytical column packed with particles bonded with phenyl-hexyl stationary phase. The chromatographic method coupled with isotope dilution tandem MS offers a simple assay enabling the simultaneous analysis of these analytes. The method employs (13)C-labeled estrogens as internal standards to eliminate potential matrix effects arising from the use of deuterated estrogens. The assay also offers adequate accuracy and sensitivity to be useful for biological samples. The practical applicability of the validated method is demonstrated by the quantitative analyses of in vivo samples obtained from rats treated with Premarin®.
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Affiliation(s)
- Szabolcs Szarka
- Department of Molecular Biology and Immunology, University of North Texas Health Science Center, Fort Worth, TX 76107-2699, USA
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Prokai L, Szarka S, Wang X, Prokai-Tatrai K. Capture of the volatile carbonyl metabolite of flecainide on 2,4-dinitrophenylhydrazine cartridge for quantitation by stable-isotope dilution mass spectrometry coupled with chromatography. J Chromatogr A 2012; 1232:281-7. [PMID: 22342210 PMCID: PMC3303990 DOI: 10.1016/j.chroma.2012.01.067] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Revised: 01/23/2012] [Accepted: 01/23/2012] [Indexed: 10/14/2022]
Abstract
Carbonyl compounds are common byproducts of many metabolic processes. These volatile chemicals are usually derivatized before mass spectrometric analysis to enhance the sensitivity of their detections. The classically used reagent for this purpose is 2,4-dinitrophenylhydrazine (DNPH) that forms the corresponding hydrazones. When DNPH is immobilized on specific cartridges it permits solvent-free collection and simultaneous derivatization of aldehydes and ketones from gaseous samples. The utility of this approach was tested by assembling a simple apparatus for the in vitro generation of trifluoroacetaldehyde (TFAA) and its subsequent capture on the attached DNPH cartridge. TFAA was generated via cytochrome P450-catalyzed dealkylation of flecainide, an antiarrhythmic agent, in pooled human liver microsomes. Stable-isotope dilution mass spectrometry coupled with GC and LC using negative chemical ionization (NCI) and electrospray ionization (ESI) was evaluated for quantitative analyses. To eliminate isotope effects observed with the use of deuterium-labeled DNPH, we selected its (15)N(4)-labeled analog to synthesize the appropriate TFAA adduct, as internal standard. Quantitation by GC-NCI-MS using selected-ion monitoring outperformed LC-ESI-MS methods considering limits of detection and linearity of the assays. The microsomal metabolism of 1.5 μmol of flecainide for 1.5h resulted in 2.6 ± 0.5 μg TFAA-DNPH, corresponding to 9.3 ± 1.7 nmol TFAA, captured by the cartridge.
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Affiliation(s)
- Laszlo Prokai
- Department of Molecular Biology and Immunology, University of North Texas Health Science Center, 3500 Camp Bowie Boulevard, Fort Worth, TX 76107-2699, USA.
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Nguyen HP, Li L, Gatson JW, Maass D, Wigginton JG, Simpkins JW, Schug KA. Simultaneous quantification of four native estrogen hormones at trace levels in human cerebrospinal fluid using liquid chromatography-tandem mass spectrometry. J Pharm Biomed Anal 2010; 54:830-7. [PMID: 21145681 DOI: 10.1016/j.jpba.2010.11.014] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Revised: 11/10/2010] [Accepted: 11/11/2010] [Indexed: 10/18/2022]
Abstract
Estrogens are known to exhibit neuroprotective effects on the brain. Their importance in this regard and in others has been emphasized in many recent studies, which increases the need to develop reliable analytical methods for the measurement of estrogen hormones. A heart-cutting two-dimensional liquid chromatography separation method coupled with electrospray ionization-tandem mass spectrometry (ESI-MS/MS) has been developed for simultaneous measurement of four estrogens, including estriol (E3), estrone (E1), 17β-estradiol (17β-E2), and 17α-estradiol (17α-E2), in human cerebrospinal fluid (CSF). The method was based on liquid-liquid extraction and derivatization of estrogens with dansyl chloride to enhance the sensitivity of ESI-based detection in conjunction with tandem mass spectrometry. Dansylated estriol and estrone were separated in the first dimension by an amide-C18 column, while dansylated 17β- and 17α-estradiol were resolved on the second dimension by two C18 columns (175 mm total length) connected in series. This is the first report of a method for simultaneous quantification of all four endogenous estrogen compounds in their dansylated form. The detection limits for E1, 17α-E2, 17β-E2, and E3 were 19, 35, 26, and 61pg/mL, respectively. Due to matrix effects, validation and calibration was carried out in charcoal-stripped CSF. The precision and accuracy were more than 86% for the two E2 compounds and 79% for E1 and E3 while the extraction recovery ranged from 91% to 104%. The method was applied to measure estrogens obtained in a clinical setting, from the CSF of ischemic trauma patients. While 17β-estradiol was present at a significant level in the CSF of some samples, other estrogens were present at lower levels or were undetectable.
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Affiliation(s)
- Hien P Nguyen
- Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, TX 76019, USA
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