Improvement of electrochemical detection of transthyretin synthetic peptide and its amino acids on carbon electrodes: Glassy carbon versus amorphous carbon nitride a-CNx

• Published in: Electrochimica acta Vol. 296; pp. 251 - 258
• Main Authors: Faure, M., Billon, F., Le Potier, I., Haghiri-Gosnet, A.-M., Tribollet, B., Pailleret, A., Deslouis, C., Gamby, J.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 10.02.2019; Elsevier BV; Elsevier
• Subjects: Amino acids; Amorphous carbon nitride; Amorphous materials; Analytical chemistry; Aqueous solutions; Carbon; Carbon nitride; Chemical Sciences; Cyclic voltammetry; Derivatives; Differential pulse voltammetry; Electrochemical analysis; Electrodes; Fluorescence; Glass; Glassy carbon; Impedance spectroscopy; Indium tin oxides; Naphthalene; Other; Oxidation; Peptides; Performance enhancement; Pretreatment; Rangefinding; Thin films; Transthyretin peptide; Cyclic voltammetry; Amorphous carbon nitride; Impedance spectroscopy; Transthyretin peptide; Differential pulse voltammetry
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2018.11.022

Amorphous carbon nitride a-CN0.26 thin films were elaborated on transparent and conductive glass/indium-tin oxide (ITO) wafers to improve the electroanalytical detection of transthyretin peptide (PN) and specific amino acids (AA) from its sequence, which constitutes a great challenge for the diagnosis of transthyretin-related familial amyloïd polyneuropathy (ATTR). The naphthalene-2,3-dicarboxyaldehyde (NDA) label was used for the derivatization reaction of PN and AAs to form N-2-substituted-1-cyanobenz-[f]-isoindole derivatives (CBI) which are both fluorescent and electroactive. The results obtained on a-CN0.26 were compared with those observed on glassy carbon (GC) as a reference material. It was shown that a soft anodic pre-treatment protocol on glass/ITO/a-CN0.26 electrode in a KCl aqueous solution drastically improved the performances of the CBI-PN and CBI-AA oxidation peak. The oxidation peak potential for all CBI derivatives varied in the same range than those measured on GC and pre-treated glass/ITO/a-CN0.26, while no discrimination could be obtained on as-grown glass/ITO/a-CN0.26 electrodes. For almost all the tested CBI derivatives, peak areas, full-widths at peak mid-height, peak current density and their standard deviation (SD) values were improved on a pre-treated a-CN0.26 electrode in comparison with GC.