In-tube solid-phase microextraction directly coupled to tandem mass spectrometry for anandamide and 2-arachidonoylglycerol determination in rat brain samples from an animal model of Parkinson's disease

Author(s)

Carvalho Oliveira, Igor Gustavo ^[1] ; de Souza, Israel Donizeti ^[1] ; do Nascimento, Glauce Crivelaro ^[2] ; Del Bel, Elaine ^[2] ; Costa Queiroz, Maria Eugenia ^[1]

Affiliation

^[1] Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Dept Quim, Ave Bandeirantes 3900, BR-14040901 Ribeirao Preto, SP - Brazil

^[2] Univ Sao Paulo, Fac Odontol Ribeirao Preto, Ave Cafe, BR-14040904 Ribeirao Preto, SP - Brazil

• Document type: Journal article
• Source: Journal of Chromatography A; v. 1636, JAN 11 2021.
• Web of Science Citations: 0

Abstract

To evaluate the endocannabinoid system in an animal model of Parkinson's disease, in-tube solid-phase microextraction (in-tube SPME) was directly coupled to a tandem mass spectrometry (MS/MS) system for determination of the endocannabinoids anandamide (AEA) and 2-arachidonoylglycerol (2-AG) in rat brain samples. In-tube SPME-which consisted of a microtube of restricted access material (RAM) with a hydrophilic diol external surface and a hydrophobic octyl inner surface-efficiently excluded (up to 95%) macromolecules from the biological samples and selectively pre-concentrated the analytes. In-tube SPME parameters, such as sample volume, mobile phases, flow rate, and pre-concentration time, were evaluated to improve the extraction efficiency and throughput performance. The selectivity of the in-tube SPME and MS/MS (MRM mode) techniques allowed them to be directly coupled online, which dismissed the need for the chromatographic separation step. The in-tube SPME-MS/MS method was validated and shown to be linear from 6.0 to 30.0 ng mL(-1) for AEA and from 10.0 to 100.0 ng mL(-1) for 2-AG; the intra-and inter-assay accuracy and precision were lower than 15%. Parallelism between the calibration curves constructed in the matrix and aqueous solution confirmed that there was no matrix effect. The method allowed endogenous concentrations of AEA and 2-AG to be determined in rat brain striatum from unilaterally 6-hydroxydopamine-lesioned animals. The concentrations of these endocannabinoids in striatum ipsilateral and contralateral to the lesion differed significantly (p<0.001). (C) 2020 Elsevier B.V. All rights reserved. (AU)

• FAPESP's process: 19/19485-0 - Development of nitinol fiber chemically coated with zwitterionic polymeric ionic liquids for determination of beta-amyloids in plasma samples from patients with Alzheimer's disease by direct coupling fiber-in-tube SPME and MS/MS
• Grantee: Israel Donizeti de Souza
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 18/06068-0 - Development of the column switching SALLE-UHPLC-MS/MS method to anandamide and 2-arachidonoylglycerol determination in brain samples of rats submitted to an animal model of Parkinsons Disease
• Grantee: Igor Gustavo de Carvalho Oliveira
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 20/00126-8 - Development of the methods of the microextraction hyphenated with LC-MS/MS or directly to MS/MS for the determination of biomarkers in biological samples of patient or rats with neurodegenerative diseases
• Grantee: Maria Eugênia Queiroz Nassur
• Support Opportunities: Regular Research Grants
• FAPESP's process: 14/50891-1 - INCT 2014: Translational Medicine
• Grantee: Jaime Eduardo Cecilio Hallak
• Support Opportunities: Research Projects - Thematic Grants