Colorimetric detection of normetanephrine, a pheochromocytoma biomarker, using bifunctionalised gold nanoparticles.

Colorimetric detection of normetanephrine, a pheochromocytoma biomarker, using bifunctionalised gold nanoparticles. Anal Chim Acta. 2019 May 16;1056:146-152 Authors: Godoy-Reyes TM, Costero AM, Gaviña P, Martínez-Máñez R, Sancenón F Abstract A simple and effective colorimetric method for the detection of normetanephrine (NMN), an O-methylated metabolite of norepinephrine, using functionalised gold nanoparticles is described. This metabolite is an important biomarker in the diagnosis of adrenal tumours such as pheocromocytoma or paraganglioma. The colorimetric probe consists of spherical gold nanoparticles (AuNPs) functionalised with two different ligands, which specifically recognize different functional groups in normetanephrine. Thus, a benzaldehyde-terminated ligand was used for the recognition of the amino alcohol moiety in NMN, by forming the corresponding oxazolidine. On the other hand, N-acetyl-cysteine was chosen for the recognition of the phenolic hydroxyl group through the formation of hydrogen bonds. The selective double molecular recognition between the probe and the hydroxyl and the amino-alcohol moieties of normetanephrine led to interparticle-crosslinking aggregation resulting in a change in the color of the solution, from red to blue, which could be observed by naked eye. The probe was highly selective towards normetanephrine and no color changes were observed in the presence of other neurotransmitter metabolites...
Source: Analytica Chimica Acta - Category: Chemistry Authors: Tags: Anal Chim Acta Source Type: research