REVIEW PAPER Electrocatalytic (bio)platforms for the determination of tetracyclines Paloma Yáñez-Sedeño 1 & María Pedrero 1 & Susana Campuzano 1 & José M. Pingarrón 1 Received: 4 May 2020 /Revised: 4 May 2020 /Accepted: 7 May 2020 # Springer-Verlag GmbH Germany, part of Springer Nature 2020 Abstract Due to their widespread use in veterinary medicine, the presence of tetracyclines (TCs) and their metabolites in foodstuffs from treated animal represents a growing concern for human health and nutrition and, therefore, many countries have established maximum levels for their presence in foods. The compliance with these legislations requires sensitive and selective methods for the determination of this antibiotics’ family in different matrices. In this sense, electrochemical sensors and biosensors are competitive methodologies versus other approaches commonly used for this purpose such as chromatography and ELISA methods, mainly in terms of low-cost equipment, minimal sample treatment, reduced turnaround time, and compatibility with multiplexed and point-of-care determinations. With this background in mind, this article reviews in a general but comprehensive way recent contributions of electrochemical (bio)sensors developed for the determination of TCs and applied to TC analysis in environmental samples, food, and biological matrices. The highlighted representative methods show the key role played both by the materials (mostly nanomaterials and polymers) employed to impart surface electrocatalytic properties and significant signal amplification, and by different (bio)receptors to provide electrochemical sensing with the sensitivity and selectivity demanded by the determination of TCs in environmental, clinical, and food samples. Main challenges to overcome and future prospects to turn over all the benefits of these simple, rapid, sensitive, selective, and cost effective electroanalytical (bio)tools in single or multiplexed TCs analysis, even at decentralized settings and after minimal sample treatment, are also pointed out. Introduction As it is well known, the global antibiotics consumption has increased significantly and their abuse can prompt residues in waters and soils. A matter of concern is the inappropriate use of these pharmaceuticals that favors their presence in animal and foods originating the emergence of allergies, resistance, and superinfections in humans [1]. Particularly, tetracycline (TC) and its derivatives (Fig. 1) constitute an important class of antibiotics with broad antibacterial spectrum and bacterio- static activity generally used to treat urinary tract infections, chlamydia, and acne [2]. They show activity against a wide range of gram-positive and gram-negative aerobic and anaer- obic bacteria, such as Spirochete, Actinomyces, Rickettsia, and Mycoplasma [3]. Tetracyclines (TCs) bind to the ribosome, block protein building, and can act as antiprotozoal, antican- cer, and antimalarial agents. TCs are extensively used as feed additives for cattle, sheep, poultry, pigs, and fish due mainly to their antibacterial properties in addition to their relatively low toxicity and low cost [4]. It is also known that TCs are not only used for treating infections but also for promoting the growth rate of livestock [5]. The widespread use of TCs in veterinary medicine has led to the generation of residues found in surface soils and water [6]. Moreover, traces of TCs or their metabolites are also found in foodstuff produced from treated animals, which rep- resents a growing concern for human health and nutrition [7–9]. For this reason, several countries and their respective legislations have established maximum residue limits (MRLs) of TCs in foods. For instance, the European Union recom- mends MRLs of 0.6 mg kg -1 (kidney), 0.2 mg kg -1 (eggs), and 0.1 mg kg -1 (milk) for TC [10, 11]. Due to these low limits, sensitive analytical methods are required for their de- termination. Chromatography including high-performance liquid chromatography with UV and diode array detection [12–14], or liquid chromatography–mass spectrometry [15, 16], are commonly used. However, sample preparation is time consuming and their implementation requires relatively ex- pensive equipment [10]. Immunoassay techniques using enzyme-linked immunosorbent assay (ELISA) kits with col- orimetric detection are also used for the analysis of food sam- ples. Competitive examples include the following: * José M. Pingarrón pingarro@quim.ucm.es 1 Departamento de Química Analítica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain Journal of Solid State Electrochemistry https://doi.org/10.1007/s10008-020-04644-9