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This review addresses the use of screen‐printed electrodes (SPEs) coupled to flow systems such as flow injection analysis (FIA), batch injection analysis (BIA), and high‐performance liquid chromatography (HPLC) systems over the last six years (since 2014). The combination of SPEs and flow systems is a powerful synergy to increase the throughput of measurements, improve electrode lifetime, and reduce reagent consumption and waste generation. Recently, commercial flow cells for SPEs were made available by different companies and potential new users that are unable to construct homemade electrochemical flow cells have been attracted to work in the area. This overview aims to show both trends and future potential for the development of new methods useful for modern electroanalysis and/or portable applications. [ABSTRACT FROM AUTHOR]

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]

Abstract: This work presents a simple electrochemical method for Hg determination in fish oil capsules using anodic stripping voltammetry (ASV) on a screen‐printed gold electrode (SPGE). Samples were treated in an ultrasonic bath for 15 min in the presence of a 1 : 1 (v/v) concentrated HCl/H2O2 mixture at room temperature. The limit of detection (LOD) was estimated as 0.25 μg L−1 (corresponding to 7.6 μg kg−1 of oil) with a linear range between 5 and 400 μg L−1 (90 s of deposition time). The analyzed fish oil samples presented Hg concentration below the LOD value. Recovery values for samples spiked with oil standard containing Hg ranged from 95 to 105 %. The method is precise (inter‐day and intra‐day RSD<4 % for n=3) as well as the SPGE sensors (RSD=4.3 %, n=3), which were used continuously (around 100 analyses without replacement) under such oxidation media. The proposed method is feasible to be applied for on‐site determinations due to the portability of sensing and sample treatment approaches. [ABSTRACT FROM AUTHOR]

This work reports the use of eucalyptus pulp as an adsorbent for metal removal from biodiesel. Fatty acid methyl esters produced from sunflower oil (SfMB) and recycled used cooking oil (RMB), which contained Fe, Mn, and Cu, were treated through filtration on a column filled with the cellulosic adsorbent, and washed with deionized water for comparison. The treatment with cellulose material resulted in the removal of 13–81%, 35–84%, and 40–74% of Fe, Mn, and Cu in biodiesels, while the water washing removed 4–40%, 10–47%, and 4–19%, respectively. In addition to the higher efficiency, the use of cellulose is a more environmentally friendly process than the purification with water, once the latter results in a considerable volume of effluent requiring treatment prior to disposal, besides the high consumption of water. Moreover, the regeneration of the cellulosic adsorbent is demonstrated. [ABSTRACT FROM AUTHOR]