Water-Based Conductive Ink for the Production of Carbon Black Screen-Printed Electrodes and the Detection of Tryptophan

Author(s)

Camargo, Jessica ; Crapnell, Robert D. ; Bernalte, Elena ; Janegitz, Bruno C. ; Banks, Craig E.

• Document type: Journal article
• Source: ACS APPLIED ELECTRONIC MATERIALS; v. 7, n. 12, p. 12-pg., 2025-06-04.

Abstract

The development of versatile, cost-effective, and reproducible electrochemical sensors has gained importance due to their adaptability to specific applications through variations in composition and design. Water-based conductive inks have emerged as environmentally friendly alternatives to meet sustainability requirements and eliminate hazardous solvents. In this study, a screen-printed electrode (SPE) sensor utilizing a water-based conductive ink composed of Carbon Black Super P (CBSP), poly(vinylpyrrolidone) (PVP) and chitosan is presented. The ink formulation was optimized for a 5% CBSP composition, resulting in a homogeneous surface and superior reproducibility with a relative standard deviation of 7.99% (n = 5). The optimized sensor exhibited quasi-reversible behavior in cyclic voltammetry and an electroactive area 198.57% larger than its geometric area. The analytical performance for tryptophan detection showed a linear range from 0.5 to 300 mu mol L-1 (R 2 = 0.9946), a limit of detection of 0.018 mu mol L-1, and interference rates below 10% for common compounds. The recovery rates for pharmaceutical and beverage samples ranged from 86.2% to 114%. The sustainable design, excellent sensitivity, and cost-effective manufacturing make this SPE sensor a robust tool for point-of-use tryptophan quantification. (AU)

• FAPESP's process: 23/06793-4 - Development of applied multiplex electrochemical systems for detection of biomarkers related to cardiovascular diseases
• Grantee: Bruno Campos Janegitz
• Support Opportunities: Regular Research Grants
• FAPESP's process: 23/00321-3 - Screen-printed carbon electrodes for the detection of clinical and pharmaceutical compounds
• Grantee: Jéssica Rocha Camargo
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate (Direct)
• FAPESP's process: 19/23177-0 - Development of disposable devices with conductive inks and low cost substrates for the biosensing of hormonal dysfunctions and detection of Malaria
• Grantee: Jéssica Rocha Camargo
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)