Laser-Induced Carbon-Based Smart Flexible Sensor Array for Multiflavors Detection.

Area of Science:

• Materials Science
• Sensor Technology
• Analytical Chemistry

Background:

• Electronic tongues offer a method for detecting multiple analytes using a single sensor array through cross-sensitivity.
• Flexible sensor platforms are desirable for versatile applications in chemical sensing.

Purpose of the Study:

• To develop and characterize a flexible sensor array electronic tongue system for multiflavor detection.
• To investigate the system's ability to detect and differentiate various analytes and their concentrations.

Main Methods:

• Fabrication of a six-unit sensor array on a flexible polyamide substrate using laser direct writing.
• Creation of porous carbon electrodes via laser-induced carbonization for high surface-volume ratio and conductivity.
• Surface modification of sensing units with gold plating, reduced graphene oxide, and polyaniline coatings.
• Utilizing Principal Component Analysis (PCA) for data analysis and flavor pattern recognition.

Main Results:

• The sensor system demonstrated effective detection of multiple flavors with a detection limit of approximately 0.1 mM for NaCl and sugar.
• Successfully detected highly diluted commercial table vinegar (5% acetic acid).
• Exhibited high sensitivity and selectivity for mixed analytes, enabling the prediction of concentration ratios.

Conclusions:

• The laser-fabricated flexible electronic tongue is a promising platform for sensitive and selective multiflavor detection.
• The system's cross-sensitivity and data analysis via PCA allow for the identification of complex flavor profiles.
• Achieved detection limits below human sensory thresholds, indicating significant potential for food and beverage analysis.