Electrochemical immunosensors for Salmonella detection in food

Abstract

Pathogen detection is a critical point for the identification and the prevention of problems related to food safety. Failures at detecting contaminations in food may cause outbreaks with drastic consequences to public health. In spite of the real need for obtaining analytical results in the shortest time possible, conventional methods may take several days to produce a diagnosis. Salmonella spp. is the major cause of foodborne diseases worldwide and its absence is a requirement of the health authorities. Biosensors are bioelectronic devices, comprising bioreceptor molecules and transducer elements, able to detect analytes (chemical and/or biological species) rapidly and quantitatively. Electrochemical immunosensors use antibody molecules as bioreceptors and an electrochemical transducer. These devices have been widely used for pathogen detection at low cost. There are four main techniques for electrochemical immunosensors: amperometric, impedimetric, conductometric, and potentiometric. Almost all types of immunosensors are applicable to Salmonella detection. This article reviews the developments and the applications of electrochemical immunosensors for Salmonella detection, particularly the advantages of each specific technique. Immunosensors serve as exciting alternatives to conventional methods, allowing "real-time" and multiple analyses that are essential characteristics for pathogen detection and much desired in health and safety control in the food industry.

Electrochemical biosensors for Salmonella: State of the art and challenges in food safety assessment

“…In the last years, various devices for rapid detection of Salmonella spp. were developed, tested and commercialized (Brandão et al, 2015;Law et al, 2015;Lee et al, 2015;Melo et al, 2016;Valderrama et al, 2016). According to current regulation for food control parameters, commercial methods should accomplish several requirements: the devices have to be able to detect a single Salmonella CFU in 25 g of food; they must have a sensitivity and specificity of at least 99%; and operational personnel ideally must need no special skills to perform the analysis (Eijkelkamp et al, 2009).…”

“…Many commercial devices for rapid foodborne pathogen detection were developed recently (Bahadır and Sezgintürk, 2015;Barthelmebs et al, 2010;Law et al, 2015;Lee et al, 2015;Melo et al, 2016;Pashazadeh et al, 2017;Valderrama et al, 2016) but, to the best of our knowledge, the examples of commercial biosensors currently available in the market are limited. The RBD 3000 Micro PRO™ and the Rapid B (Valderrama et al, 2016) biosensors requires flow cytometry equipment and trained personal to perform the analysis and treat the output data.…”

“…is a figurative quantification, since "zero" in analytical measures is unreal, because each method has a limit of detection and there are always errors associated. Even the conventional culture methods recommended by International Organization for Standardization (ISO) (ISO standard 6579:2002) due to their exceptional sensitivity (Melo et al, 2016) are only capable to detect 1 CFU/ 25 g of foodstuffs.…”

Electrochemical Affinity Biosensors in Food Safety

“…Electrochemical immunosensors, genosensors and phagosensors for this particular application were reviewed by Liébana et al [130]. More recently, Araújo et al also reviewed the reported designs of electrochemical immunosensors for Salmonella detection in food [131].…”

Reduced Graphene Oxide-Based Impedimetric Immunosensor for Detection of Enterotoxin A in Milk Samples

“…The main techniques used to detect SEs include the enzyme immunoassay ELISA (enzyme-linked immunosorbent assay), Optimum Sensitivity Plate (OSP), and Polymerase Chain Reaction (PCR), adapted to meet the needs involving time spent for analysis and specificity and sensitivity for detection. Even so, these methods require at least 24 h to 72 h for each analysis and sample pre-treatments in order to reduce interference caused by agents contained in the samples themselves, and in the case of PCR, the detection of enterotoxin coding genes does not imply their presence in the sample [6,7].…”