Chemiluminometric evaluation of melatonin and selected melatonin precursors' interaction with reactive oxygen and nitrogen species

• Type: Article in International Scientific Journal
• Date: 2012

Authors

Joanna Harasimowicz (Author) Other; Karine L Marques (Author) Other; Ana F T Silva (Author) Other; Renata C B Costa (Author) Other; Joao A V Prior (Author) FFUP; Sofia S M Rodrigues (Author) Other; Joao L M Santos (Author) FFUP

Journal

Title: Analytical Biochemistry

Vol. 420

Pages: 1-6

ISSN: 0003-2697

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 8 Citations

Scopus - 13 Citations

Scientific classification

FOS: Natural sciences > Chemical sciences

Other information

Authenticus ID: P-002-HJM

DOI: 10.1016/j.ab.2011.09.008

Abstract (EN): Melatonin is a hormone, a derivative of tryptophan, that possesses a potent scavenging capacity for the most reactive and dangerous free radicals, being an important protection against oxidative stress. In this work, an automated flow-based procedure for assessment of melatonin, tryptophan, and 5-hydroxytryptophan scavenging capacity was developed. The presented methodology involved a multi-pumping flow system and exploited the ability of selected compounds to inhibit the chemiluminescence reaction of luminol with hydrogen peroxide, hydroxyl radical, and peroxynitrite anion. The system was based on the use of several solenoid actuated micro-pumps as the only active components of the flow manifold. This enabled the reproducible insertion and efficient mixing of very low volumes of sample and reagents as well as the transportation of the sample zone toward detection for monitoring the chemiluminometric response. Furthermore, the high versatility of the proposed multi-pumping flow system allowed the implementation of distinct reactions for the in-line generation of the different reactive species assayed without requiring physical reconfiguration. The results obtained demonstrated that 5-hydroxytryptophan is the most potent scavenger, followed by melatonin and tryptophan. The developed multi-pumping flow system exhibited good measurement precision (relative standard deviations typically <2%, n = 10), low operational costs, and low reagent consumption.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 6