Ultrasensitive Detection of Gallic Acid via Synergistic Enhancement of Single-Walled Carbon Nanotubes@Zeolitic Imidazolate Framework-8: Comprehensive Innovative Experiment for Undergraduates

Gallic acid (GA) with strong antioxidant and antibacterial properties has been widely used in the food and pharmaceutical industries. However, excessive GA may induce gastrointestinal irritation and impose metabolic burdens on the liver and kidneys. Herein, we developed a novel electrochemical sensor based on the single-walled carbon nanotubes@zeolitic imidazolate framework-8 decorated electrode (SCT@ZMF/GCE) for the ultrasensitive detection of GA. SCT with a hollow nanotube structure provided excellent conductivity properties because of the interconnected conductive carbon networks, and ZMF nanoparticles with high porosity exhibited strong adsorption capacity for GA molecules. SCT@ZMF/GCE displayed exceptional GA detection (Linear detection range: 0.1–30 μM; limit of detection: 7.84 nM). This comprehensive innovative experiment was designed for senior undergraduate students majoring in materials science, chemistry, and other related fields. This experiment contains a literature review, nanocomposite preparation, material characterization, electrochemical detection, and data processing. Integrating this experiment into undergraduate teaching will help participants achieve the following objectives: (1) understanding the importance of GA concentration for human health; (2) designing a simple, low-cost, and innovative GA analysis method; (3) optimizing the electrochemical detection condition; and (4) mastering the GA detection mechanism and strengthening the experimental skills and scientific literacy.