Electrochemical Sensor for Bilirubin Detection Using Screen Printed Electrodes Functionalized with Carbon Nanotubes and Graphene

Abstract

Practice oriented point-of-care diagnostics require easy-to-handle, miniaturized, and low-cost analytical tools. In a novel approach, screen printed carbon electrodes (SPEs), which were functionalized with nanomaterials, are employed for selective measurements of bilirubin, which is an important biomarker for jaundice. Multi-walled carbon nanotubes (MWCNT) and graphene separately deposited on SPEs provide the core of an electrochemical sensor for bilirubin. The electrocatalytic activity towards bilirubin oxidation (bilirubin to biliverdin) was observed at +0.25 V. In addition, a further peak corresponding to the electrochemical conversion of biliverdin into purpurin appeared at +0.48 V. When compared to MWCNT, the graphene type shows a 3-fold lower detection limit (0.3 ± 0.022 nM and 0.1 ± 0.018 nM, respectively), moreover, the graphene type exhibits a larger linear range (0.1–600 µM) than MWCNT (0.5–500 µM) with a two-fold better sensitivity, i.e., 30 nA µM−1 cm−2, and 15 nA µM−1 cm−2, respectively. The viability is validated through measurements of bilirubin in blood serum samples and the selectivity is ensured by inhibiting common interfering biological substrates using an ionic nafion membrane. The presented approach enables the design and implementation of low cost and miniaturized electrochemical sensors.

Broad-Spectrum Theranostics and Biomedical Application of Functionalized Nanomaterials

“…The separate deposition of graphene and multi-walled carbon nanotubes (MWCNT) on screen-printed carbon electrodes (SPE) offersthe electrochemical sensor core for the detection of bilirubin and is evaluated for electroanalytical parameters, such as higher sensitivity, wider linear range and lower detection limit. The data suggested that SPE-based bilirubin sensors can beessential for the management of healthcare and can be used for care diagnosis [ 67 ].…”

Metal Nanoparticles and Carbon-Based Nanomaterials for Improved Performances of Electrochemical (Bio)Sensors with Biomedical Applications

“…Graphene oxide were electrochemically reduced to the SPE surface. Better electroanalytical parameters have been recorded in the case of SPE modified with graphene, explained by a more enhanced electron transfer rate and a higher surface area calculated by electrochemical measurements [ 232 ]. A paper-based sensor was fabricated using graphene and carbon ink for the WE printing.…”

Graphene- and Graphene Oxide-Based Nanocomposite Platforms for Electrochemical Biosensing Applications

“…Electrochemical detection of clinically important biomarkers using non-enzymatic electrodes fabricated using graphene-based nanomaterials is an another important application. Thangamuthu et al developed a non-enzymatic sensor for bilirubin detection, an important biomarker of jaundice, using ErGO [42]. In a screen-printed carbon electrode, ErGO was functionalized and its electrochemical activity towards bilirubin was comparatively studied with MWCNT functionalized electrode.…”

“…( C ) CV profiles of the MGNF electrodes in the solution of 50 mM, pH 7.0 PBS with 1 mM AA, 0.1 mM DA, and 0.1 mM UA. Figures reproduced with permission from: ( A ) [42], MDPI © ; ( B ) [104], Elsevier © ; and ( C ) [105], Wiley Interscience © .…”

“…These oxygen and defect sites could allow for better binding of biomolecules, support efficient electrical wiring of the redox centers of the metalloproteins to the electrode, and improve specificity when multiple analytes are present. Since such defects lead to the higher density of electronic states at the Fermi level, they also help reduce the overpotential associated with biosensing [41,42].…”