Emerging contaminants: the application of a homemade electrochemical IoT-enabled device to solve a global challenge

• Need for robust, useful devices for monitoring emerging environmental contaminants • Simultaneous voltammetric detection of paracetamol, salicylic acid, and carbamazepine • Recovery studies of globally used drugs in river and tap water • Chromatographic studies of PAR+SA+CBZ and comparison with electrochemical results • Application of 2 portable strategies: commercial SensitSmart and homemade IoT device Pharmaceuticals have emerged as contaminants in aquatic ecosystems, challenging the water quality concept. These compounds enter wastewater treatment plants, where inefficient treatments pose concerns for long-term river and tap water quality, consequently impacting environmental and human health. Considering this, the present study first reports the simultaneous quantification of paracetamol, salicylic acid, and carbamazepine by electrochemistry with carbon screen-printed electrodes, as well as liquid chromatography-tandem mass spectrometry (LC-MS/MS). At pH 7.4 and by optimized DPV, LODs were 0.783, 1.53, and 0.113 μM for paracetamol, salicylic acid, and carbamazepine, respectively. The recovery values obtained by LC-MS/MS in tap water are not satisfactory regarding the data obtained in river water with DPV electrochemical experiments. Moreover, in both analytical methods, the highest sensitivity was obtained for carbamazepine, with the lowest RSD values. These analytical data highlight the remarkable sensitivity and detection skills of DPV and LC-MS/MS analysis. Developing portable potentiostats for in situ pharmaceutical detection and monitoring outside the labs is crucial for ensuring environmental and health safety. Herein two portable approaches are tested: commercial SensitSmart® and homemade electrochemical Internet-of-Things (IoT)-enabled devices. The results of SensitSmart® are reliable but lower than those obtained with a benchtop potentiostat and require a USB connection with PCs, tablets, or smartphones. The practical application of a homemade IoT device was validated with potassium ferricyanide with an output similar to benchtop potentiostat, which represents a proof of concept.