Electrochemical sensor based on PGE/MWCNT/Cu-BTC for simultaneous determination of vitamins B2, B6, and C in biological and dietary samples

Yıldırım Baştemur G.

JOURNAL OF MATERIALS SCIENCE: MATERIALS IN ELECTRONICS, vol.37, no.2, pp.1-16, 2026 (Scopus)

Abstract

In this study, a novel electrochemical sensor was developed for the sensitive and

rapid simultaneous determination of riboflavin (B2), pyridoxine (B6) and ascorbic

acid (C) in biological samples and dietary supplements using voltammetric

techniques. For this purpose, pencil graphite electrode (PGE) was modified with

multi-walled carbon nanotubes (MWCNTs) and copper based metal–organic

framework (Cu-BTC). The electrochemical and surface characterizations of the

sensor were carried out using cyclic voltammetry, electrochemical impedance

spectroscopy (EIS), scanning electron microscopy (SEM) and Fourier transform

infrared spectroscopy (FTIR). To optimize the sensor’s performance, the effects

of electrochemical activation time, MWCNT suspension amount, deposition

time, Cu-BTC concentration, cycle number and supporting electrolyte and

pH were systematically investigated. Differential pulse voltammetry (DPV)

measurements revealed linear detection ranges of 0.1–100 μM for B2, 5–200 μM

for B6, and 1–1000 μM for C, with detection limits of 0.021 μM, 0.011 μM, and

0.071 μM, respectively. Additionally, repeatability, reproducibility, stability, and

interference studies were conducted. The sensor’s applicability in real biological

samples and dietary supplements was evaluated, yielding high recovery values.

These results confirm that the modified electrode is a reliable and efficient

platform for the simultaneous determination of B2, B6, and C.