Challenging genosensors in food samples: The case of gluten determination in highly processed samples

Electrochemical Affinity Biosensors in Food Safety

“…They are classified according to the type of used bioreceptor. The bioreceptors most commonly used are specific antibodies [93][94][95][96][97][98][99][100][101][102][103][104], single-stranded DNA molecules [105][106][107][108], aptamers [109][110][111][112], and other affinity receptors like lectins [113] and peptides [114]. The affinity reaction between these bioreceptors, which are immobilized onto electrodes or solid supports like magnetic beads (MBs), and the target allergen has been monitored using (chrono)amperometry [68,94,97,99,[101][102][103][104]109], voltammetry [93,95,96,98,102,103,106,107,[112][113][114] and electrochemical impedance spectroscopy [105,110,111].…”

“…Regarding DNA sensors, all the reported works use specific thiolated probes self-assembled on gold electrodes [105] or AuNPs-modified electrodes [106][107][108]. While linear DNA probes were used for the implementation of sandwich hybridization assays for the determination of Ara h 2 [107] and α2-gliadin [108], direct assays were implemented for Ara h 1 determination using dual-labeled stem-loop probes [105,106].…”

“…While linear DNA probes were used for the implementation of sandwich hybridization assays for the determination of Ara h 2 [107] and α2-gliadin [108], direct assays were implemented for Ara h 1 determination using dual-labeled stem-loop probes [105,106]. The strategy developed by Martin-Fernández et al [108] is based on sandwich hybridization of target DNA with a thiolated capture probe immobilized together with MCH onto Au-SPEs and a fluorescein isothiocyanate (FITC)-modified detector probe. After labeling the FITC-modified sandwich duplex with an antiFITC-HRP conjugate, the hybridization event was electrochemically monitored by chronoamperometry upon addition of tetramethylbenzidine (TMB) and H 2 O 2 .…”

“…In addition, given the sensitivity required for some allergens detection, many biosensor devices with improved sensitivity based on the use of nanomaterials, such as QDs [115], AuNPs [93,100,101,[106][107][108], MWCNTs [93] and graphene [95,96,106] have been developed. Worth to mention also the increasing tendency to fabricate these electrochemical biosensors onto screen-printed electrodes (SPEs) [85,[95][96][97][98][99][100][101][102][103][104]107,109,112,113] since they are suitable to be fabricated with different materials, to be drawn in diverse geometries and multiplexed formats and Recently, Sugawara et al [116] developed an electrochemical biosensor to detect ovalbumin (OVA) by adsorbing a specific peptide probe (peptide-1) conjugated with the electroactive daunomycin on a GCE.…”

“…Particularly relevant is the progress in the determination of gluten content in food, ensuring the celiac disease sensitized population safety [109]. In this sense, it is worth to mention that although quantification of food allergens using genosensors is a challenging task which has been rarely addressed probably because results in terms of DNA concentration are meaningless for consumers which need often yes/no tools, a genosensor that allows for the first time to quantify the gluten content in food products has been described recently [108].…”