Ratio electrochemical sensing strategy based on hemin/CNT/Ti₃C₂T_x for highly sensitive detection of synephrine in...

Synephrine (SPR) is a characteristic marker of citrus honey, the presence and content of SPR can be used to judge whether citrus honey is authentic. In this work, an innovative ratio electrochemical sensing strategy based on hemin modified carbon nanotube decorated titanium carbide (Hemin/CNT/Ti₃C₂T_x) was developed to enable performance-improving SPR detection for distinguishing the authenticity of citrus honey. Hemin/CNT/Ti₃C₂Tₓ was synthesized as a functional hybrid material, where Ti₃C₂Tₓ is modified with Hemin-functionalized CNT, and the material displays redox catalytic activity. Via systematic characterization, it was confirmed that Hemin/CNT/Ti₃C₂Tₓ has good electrochemical sensing performance, benefiting from its excellent enrichment capacity, high electrical conductivity, and the superior catalytic activity. Based on the differential pulse voltammetry (DPV) method, the SPR was determined using a highly anti-interference ratio electrochemical sensing strategy that is suitable for complex matrix samples. Under the optimized experimental conditions, a linear relationship between I_SPR/I_hemin and the concentrations of SPR was established in the range of 1-100 μM, the limit of detection was down to 0.036 μM. The modified electrode also showed good repeatability, stability and anti-interference ability. More importantly, the successful implementation of the proposed sensing strategy allowed for the specific identification of authentic citrus honey based on synephrine levels in samples, thereby providing a robust guarantee for quality control of citrus honey. Furthermore, this sensing strategy has yielded broad-ranging and constructive effects for both food safety governance and the protection of consumer rights.