scholarly journals Rapid and sensitive quantitation of glucose and glucose phosphates derived from storage carbohydrates using gas chromatography mass spectrometry

2019 ◽  
Author(s):  
Lyndsay E.A. Young ◽  
Corey O. Brizzee ◽  
Jessica K. A. Macedo ◽  
Matthew S. Gentry ◽  
Ramon C. Sun
Keyword(s):  
Mass Spectrometry ◽  
Skeletal Muscle ◽  
Gas Chromatography ◽  
Dynamic Range ◽  
High Sensitivity ◽  
Phosphate Esters ◽  
Gas Chromatography Mass Spectrometry ◽  
Glucose Phosphate ◽  
Storage Carbohydrate ◽  
Highly Sensitive

ABSTRACTGlycogen is the primary storage carbohydrate in mammals and it is synthesized in most tissues. Glycogen contains covalently attached phosphate groups on hydroxyls of glucose units. The addition of phosphate modulates branching pattern, granular size, and crystallinity of a glycogen molecule, which all impact its accessibility to glycogen interacting enzymes during catabolism. As glycogen architecture modulates its role in metabolism, it is essential to accurately evaluate and quantify phosphate content in glycogen. Simultaneous quantitation of glucose and its phosphate esters is challenging and requires an assay with high sensitivity and a robust dynamic range. Currently, this method is lacking in the field. Herein, we describe a highly-sensitive method for the detection of both glycogen-derived glucose and glucose-phosphate esters utilizing gas-chromatography coupled mass spectrometry. Using this method, we observed higher glycogen levels in the liver compared to skeletal muscle, but skeletal muscle contained much more phosphate esters. These results confirm previous findings and establish the validity of the method. Importantly, this method can detect femtomole levels of glucose and glucose phosphate esters within an extremely robust dynamic range with excellent accuracy and reproducibility. The method can also be easily adapted for the quantification of glucose from plant starch, amylopectin or other biopolymers as well as covalently attached phosphate within them.

scholarly journals Ultra-High Performance Liquid Chromatography-High Resolution Mass Spectrometry and High-Sensitivity Gas Chromatography-Mass Spectrometry Screening of Classic Drugs and New Psychoactive Substances and Metabolites in Urine of Consumers

2021 ◽  
Vol 22 (8) ◽  
pp. 4000
Author(s):  
Emilia Marchei ◽  
Maria Alias Ferri ◽  
Marta Torrens ◽  
Magí Farré ◽  
Roberta Pacifici ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Mobile Phase ◽  
High Performance ◽  
High Resolution Mass Spectrometry ◽  
High Sensitivity ◽  
Gas Chromatography Mass Spectrometry ◽  
New Psychoactive Substances ◽  
Psychoactive Substances ◽  
Resolution Mass

The use of the new psychoactive substances is continuously growing and the implementation of accurate and sensible analysis in biological matrices of users is relevant and fundamental for clinical and forensic purposes. Two different analytical technologies, high-sensitivity gas chromatography-mass spectrometry (GC-MS) and ultra-high-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) were used for a screening analysis of classic drugs and new psychoactive substances and their metabolites in urine of formed heroin addicts under methadone maintenance therapy. Sample preparation involved a liquid-liquid extraction. The UHPLC-HRMS method included Accucore™ phenyl Hexyl (100 × 2.1 mm, 2.6 μm, Thermo, USA) column with a gradient mobile phase consisting of mobile phase A (ammonium formate 2 mM in water, 0.1% formic acid) and mobile phase B (ammonium formate 2 mM in methanol/acetonitrile 50:50 (v/v), 0.1% formic acid) and a full-scan data-dependent MS2 (ddMS2) mode for substances identification (mass range 100–1000 m/z). The GC-MS method employed an ultra-Inert Intuvo GC column (HP-5MS UI, 30 m, 250 µm i.d, film thickness 0.25 µm; Agilent Technologies, Santa Clara, CA, USA) and electron-impact (EI) mass spectra were recorded in total ion monitoring mode (scan range 40–550 m/z). Urine samples from 296 patients with a history of opioid use disorder were examined. Around 80 different psychoactive substances and/or metabolites were identified, being methadone and metabolites the most prevalent ones. The possibility to screen for a huge number of psychotropic substances can be useful in suspected drug related fatalities or acute intoxication/exposure occurring in emergency departments and drug addiction services.

scholarly journals Sensitive Gas Chromatography-Mass Spectrometry Method for Simultaneous Measurement of MDEA, MDMA, and Metabolites HMA, MDA, and HMMA in Human Urine

2006 ◽  
Vol 52 (9) ◽  
pp. 1728-1734 ◽  
Author(s):  
Stephane O Pirnay ◽  
Tsadik T Abraham ◽  
Marilyn A Huestis
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Human Urine ◽  
Simultaneous Measurement ◽  
Dynamic Range ◽  
Solid Phase ◽  
Gas Chromatography Mass Spectrometry ◽  
Spectrometry Method ◽  
Mass Spectrometry Method ◽  
Chromatography Mass Spectrometry

Abstract Background: A sensitive gas chromatography-mass spectrometry method was developed and validated for the simultaneous measurement of MDEA, MDMA, and its metabolites, 3,4-methylenedioxy-N-ethylamphetamine (MDEA), 3,4-methylenedioxymethamphetamine (MDMA or Ecstasy), and its metabolites, 4-hydroxy-3-methoxyamphetamine (HMA), 3,4-methylenedioxyamphetamine (MDA), and 4-hydroxy-3-methoxyamphetamine (HMMA) in human urine. Methods: We hydrolyzed 1 mL urine, fortified with MDMA-d5, MDA-d5, and MDEA-d6, with 100 μL of concentrated hydrochloric acid at 120 °C for 40 min, then added 100 μL 10 N sodium hydroxide and 3 mL phosphate buffer 0.1 N (pH 6.0) were added to hydrolyzed urine specimens before solid-phase extraction. After elution and evaporation, we derivatized extracts with heptafluorobutyric acid anhydride and analyzed with gas chromatography-mass spectrometry operated in EI-selected ion-monitoring mode. Results: Limits of quantification were 25 μg/L for MDEA, MDMA, and its metabolites. Calibration curves were linear to 5000 μg/L for MDEA, MDMA, HMA, MDA, and HMMA, with a minimum r2 > 0.99. At 3 concentrations spanning the linear dynamic range of the assay, mean overall extraction efficiencies from urine were >85.5% for all compounds of interest. Intra- and interassay imprecisions, produced as CV, were <15% for all drugs at 30, 300, and 3000 μg/L. Conclusions: This gas chromatography-mass spectrometry assay provides adequate sensitivity and performance characteristics for the simultaneous quantification of MDEA, MDMA, and its metabolites HMMA, MDA, and HMA in human urine. The method meets and exceeds the requirements of the proposed Substance Abuse and Mental Health Services Administration’s guidelines for federal workplace drug testing of MDEA and MDMA in urine.

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