This review provides a brief overview of the fabrication and properties of screen-printed electrodes and details the different opportunities to apply them for the detection of antibiotics, detection of bacteria and antibiotic susceptibility. Among the alternative approaches to costly chromatographic or ELISA methods for antibiotics detection and to lengthy culture methods for bacteria detection, electrochemical biosensors based on screen-printed electrodes present some distinctive advantages. Chemical and (bio)sensors for the detection of antibiotics and assays coupling detection with screen-printed electrodes with immunomagnetic separation are described. With regards to detection of bacteria, the emphasis is placed on applications targeting viable bacterial cells. While the electrochemical sensors and biosensors face many challenges before replacing standard analysis methods, the potential of screen-printed electrodes is increasingly exploited and more applications are anticipated to advance towards commercial analytical tools.

In this work we investigate the performance of a simple, disposable electrochemical aptasensor for lysozyme and its usefulness for monitoring the allergen risk along wine production. The sensor relies on screen‐printed gold electrodes modified with gold nanoparticles as the electrochemical transducer, with detection by cyclic voltammetry. This simple method is characterized by a detection limit of 0.32 μg.mL−1 lysozyme and a linear range of 1–10 μg.mL−1, being appropriate for the analysis of lysozyme‐treated wines. Several white wines where sulphur dioxide was partially replaced by lysozyme were produced and analyzed with the aptasensor at critical stages during wine production. The results obtained with the aptasensor were moreover compared with those recorded in parallel by a standard method, high performance liquid chromatography (HPLC). The specific advantages brought by the use of nanomaterial and the limitations of the sensor are discussed. The sensor allowed evaluating the effect of various technological steps along wine production on the content of lysozyme.

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Nanomaterials used in tandem with electrochemical mediators on screen‐printed electrodes enable sensitive, low cost detection of NADH with minimal interferences in real‐world samples. In this work we investigated the combination between the mediator Meldola Blue and several types of commercial screen‐printed carbon electrodes, i. e. modified with mesoporous carbon, single wall carbon nanotubes, graphene or carbon nanofibers (CNF) as NADH detectors. The sensors were compared with bare carbon electrodes and with commercially available Meldola Blue‐modified electrodes. The best sensitivity for NADH detection by amperometry was observed for Meldola Blue/CNF electrodes, and further improvement was obtained by mixing the mediator with graphene oxide prior to dropcasting. The “MB‐erGO/CNF” sensors obtained were characterized by a detection limit of 0.5 μM, a linear range of 1–300 μM and a sensitivity of 80.0±2.5 μA cm−2 mmol−1 L, 10 times higher than that of commercial sensors. While the use of graphene oxide lead to enhanced sensitivity and wider linear range, it didn't improve the operational stability as the mediator gradually desorbed from the electrodes. Furthermore, the sensors were coupled with a new NAD+‐dependent aldehyde dehydrogenase from a psychrophilic bacterium for the analysis of benzaldehyde and proven to be advantageous over commercial electrodes with Meldola Blue in circumstances where the detection was limited by NADH detection, i. e. at pH 9.5.

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