Nanosensors Made of Halloysite and Kojic Acid Metal Complexes for Dopamine Detection

A nanocomposite sensor has been developed by integrating halloysite nanotubes (HNTs), kojic acid (K), and Cu²⁺ ions (HNTK-Cu), marking a significant advancement in the field of dopamine detection. This cutting-edge sensor leverages the synergistic properties of its components to deliver exceptional analytical performance with promising implications for biomedical diagnostics and food safety monitoring. This innovative sensor exploits the unique properties of halloysite nanotubes and kojic acid to achieve a superior performance. Among its most notable features, the HNTK-Cu sensor exhibits exceptional sensitivity, reaching a limit of detection (LOD) of as low as 68 nM, enabling the accurate quantification of even trace levels of dopamine. Furthermore, it demonstrates remarkable selectivity, effectively discriminating dopamine from structurally similar or commonly interfering substances, a crucial requirement for reliable real-world applications. The sensor also offers excellent operational stability, maintaining a consistent performance across multiple detection cycles, which is critical for long-term and repetitive reuse. From a synthetic standpoint, the fabrication of the HNTK-Cu nanocomposite is both straightforward and environmentally friendly, representing a sustainable and cost-effective alternative to conventional dopamine sensors. Notably, the HNTK-Cu sensor has demonstrated the capability to perform electrochemical detection in complex matrices, including food samples and fetal bovine serum, underscoring its immediate applicability in practical scenarios. The sensor's superior performance arises from the unique synergy between its components: the high surface area and robust mechanical/thermal stability of halloysite nanotubes and the strong metal-chelating ability of kojic acid, which enhances both the loading and coordination of Cu²⁺ ions, critical to the sensor's electrochemical activity.