Novel porous iron phthalocyanine based metal–organic framework electrochemical sensor for sensitive vanillin detection

Vanillin is widely used as a flavor enhancer and is known to have numerous other interesting properties, including antidepressant, anticancer, anti-inflammatory, and antioxidant effects. However, as excess vanillin consumption can affect liver and kidney function, simple and rapid detection methods for vanillin are required. Herein, a novel electrochemical sensor for the sensitive determination of vanillin was fabricated using an iron phthalocyanine (FePc)-based metal–organic framework (MOF). Scanning electron microscopy and transmission electron microscopy showed that the FePc MOF has a hollow porous structure and a large surface area, which impart this material with high adsorption performance. A glassy carbon electrode modified with the FePc MOF exhibited good electrocatalytic performance for the detection of vanillin. In particular, this vanillin sensor had a wide linear range of 0.22–29.14 μM with a low detection limit of 0.05 μM (S/N = 3). Moreover, the proposed sensor was successfully applied to the determination of vanillin in real samples such as vanillin tablets and human serum.