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Abstract Energy demand for modern society is ubiquitous and the liquid fuels play important role in this context. The market acceptance of liquid fuels depends on a highly rigorous quality control, which requires accurate and precise analytical methods to monitor the chemical parameters established by regulatory agencies. Fast and on-site monitoring of the quality parameters of fuels can be achieved by electrochemical techniques using disposable sensors, such as screen-printed electrodes (SPEs). This revision is devoted to recent development and application of SPEs to monitor quality parameters of liquid fuels (fossil fuels and biofuels), including the determination of organic and inorganic analytes using voltammetric or amperometric detection. Trends of SPE technology for quality control of fuels, based on the reported electrochemical methods that may be considered by regulatory agencies, are highlighted. Highlights • Screen-printed electrodes (SPE) for on-site quality control of fossil fuels and biofuels. • Voltammetric and amperometrci detection of (in) organic contaminants and additives. • Regulatory agencies define severe limits to substances that can be detected on SPE. • Substrate material and chemical modifiers selected to be compatible with liquid fuels. • Perspective on new platforms to detect adulteration and for quality control on-site. [ABSTRACT FROM AUTHOR]

This work presents a portable electrochemical system for the continuous monitoring of corrosion inhibitors in a wide range of matrices including ethanol, seawater and mineral oil following simple dilution of the samples. Proof-of-concept is demonstrated for the sensing of 2,5-dimercapto-1,3,5-thiadiazole (DMCT), an important corrosion inhibitor. Disposable screen-printed graphitic electrodes (SPGEs) associated with a portable batch-injection cell are proposed for the amperometric determination of DMCT following sample dilution with electrolyte (95% v/v ethanol + 5% v/v 0.1 mol L -1 H 2 SO 4 solution). This electrolyte was compatible with all samples and the organic-resistant SPGE could be used continuously for more than 200 injections (100 µL injected at 193 µL s -1 ) free from effects of adsorption of DMCT, which have a great affinity for metallic surfaces, and dissolution of the other reported SPGE inks which has hampered prior research efforts. Fast (180 h -1 ) and precise responses (RSD < 3% n = 10) with a detection limit of 0.3 µmol L -1 was obtained. The accuracy of the proposed method was attested through recovery tests (93–106%) and the reasonable agreement of results of DMCT concentrations in samples analyzed by both proposed and spectrophotometric (comparative) methods. [ABSTRACT FROM AUTHOR]