The Simultaneous Electrochemical Sensing of Magnolol and Honokiol in Traditional Chinese Medicine based on Copper Chelated Porous Coordination Network

Magnolol and honokiol are significant phenolic isomers derived from Magnolia officinalis and are considered promising candidates for potent anticancer drugs. A convenient and rapid method for the simultaneous analysis of magnolol and honokiol is essential for investigating their mechanisms of action and pharmacokinetics. In this study, we developed a composite electrode based on a copper-chelated porous coordination network (PCN-224(Cu)) and carbon nanotubes (CNT). Experimental results demonstrated that the PC-CNT/GCE exhibited a substantial redox potential difference (∼0.14 V) between magnolol and honokiol under differential pulse voltammetry. The modified electrode enabled the simultaneous detection of both compounds in a mixture, showing a linear increase in response current with detection limits (LOD = 3σ/s) of 2.65 μM for magnolol and 11.4 μM for honokiol. Additionally, the sensor exhibited sensitivities of 54.894 μA mM−1 for honokiol and 46.677 μA mM−1 for magnolol. These findings suggest that PCN-224(Cu)-based electrodes hold great potential for the efficient analysis of phenolic isomers in Magnolia officinalis. Furthermore, this study provides a foundation for new applications of porous coordination networks in electrochemical sensing.