Protocol for the quantification of melatonin and AFMK in cerebrospinal fluid by LC-MS/MS

  • STAR Protoc. 2025 Oct 23;6(4):104145. doi: 10.1016/j.xpro.2025.104145.
Francisco Artime-Naveda  1 ,  David Hevia-Sánchez  2 ,  Adriana González-Gago  3 ,  Pablo Rodríguez-González  4 ,  Anna Zawadzka  5 ,  Rosa M Sainz  2 ,  Juan C Mayo  6
Affiliations
  • 1. Departamento de Morfología y Biología Celular, Faculty of Medicine, University of Oviedo, Julián Clavería, 6, 33006 Oviedo, Spain.
  • 2. Departamento de Morfología y Biología Celular, Faculty of Medicine, University of Oviedo, Julián Clavería, 6, 33006 Oviedo, Spain; Instituto Universitario de Oncología del Principado de Asturias (IUOPA), University of Oviedo, Fernando Bongera s/n, 33006 Oviedo, Spain; Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Avda. Hospital Universitario s/n, 33011 Oviedo, Spain.
  • 3. Departamento de Química Física y Analítica, Faculty of Chemistry, University of Oviedo, Avda. Julián Clavería, 8, 33006 Oviedo, Spain.
  • 4. Instituto Universitario de Oncología del Principado de Asturias (IUOPA), University of Oviedo, Fernando Bongera s/n, 33006 Oviedo, Spain; Departamento de Química Física y Analítica, Faculty of Chemistry, University of Oviedo, Avda. Julián Clavería, 8, 33006 Oviedo, Spain.
  • 5. Laboratory of Natural Products Chemistry, Faculty of Chemistry, University of Warsaw, Pasteura Str 1, 02-093 Warsaw, Poland.
  • 6. Departamento de Morfología y Biología Celular, Faculty of Medicine, University of Oviedo, Julián Clavería, 6, 33006 Oviedo, Spain; Instituto Universitario de Oncología del Principado de Asturias (IUOPA), University of Oviedo, Fernando Bongera s/n, 33006 Oviedo, Spain; Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Avda. Hospital Universitario s/n, 33011 Oviedo, Spain. Electronic address: [email protected].
PMID: 41134672 DOI: 10.1016/j.xpro.2025.104145
Abstract

Melatonin and its oxidant derivative, N-acetyl-N-formyl-5-methoxykynuramine (AFMK), are indolamines present in higher organisms, which are related to light-darkness circadian rhythms and redox physiology. Here, we present a protocol for the quantification of both in cerebrospinal fluid (CSF). We describe steps for standardization by isotopic dilution or alternatively by internal standard 5-methoxytryptophol (5-MT). We then detail procedures for quantification by using liquid chromatography coupled to tandem mass spectrometry. For complete details on the use and execution of this protocol, please refer to Artime-Naveda et al.1.

Keywords
Cell Biology; Health Sciences; Mass Cytometry; Neuroscience.
Products