Chronoamperometric magnetogenosensing for simultaneous detection of two Roundup Ready™ soybean lines: GTS 40-3-2 and MON89788

Abstract

Development of expeditious analytical methods for the detection of genetically modified organisms (GMOs) is increasingly necessary, not only to verify compliance with labelling, but also to help industry to efficiently control the reception of raw materials. On the basis of this, a disposable electrochemical magnetogenoassay is proposed for simultaneous detection of two Roundup Ready (RR) soybean lines GTS 40-3-2 and MON89788, using gold-coated magnetic nanoparticles (Fe3O4@Au) as nanosupport. To perform this magnetogenoassay, a sandwich-type hybridization assay was used with different enzymatic labelling systems (fluorescein isothiocyanate and digoxigenin) and dual screen-printed carbon electrodes (SPdCEs), which allowed the simultaneous readout of each target. A linear relationship ranging from 0.1 to 2.5 nM and from 0.1 to 1.0 nM was achieved for GTS-40-3-2 and MON89788 events, respectively, and both assays showed a similar detection limit of about 0.1 nM. Furthermore, a good performance in terms of precision and selectivity was achieved. The proposed approach is a step forward for event-specific multiplex detection.

Electrochemical Affinity Biosensors Based on Selected Nanostructures for Food and Environmental Monitoring

“…However, these nanoparticles (MNPs) are more prone to agglomerate and to suffer losses during their more challenging handling than their micrometric analogues [ 15 , 16 ]. In electrochemical biosensing approaches, MNPs have been used mainly as nanosurfaces where affinity conjugation takes place without the need for applying costly and complicated modification procedures to the electrode platforms [ 17 , 18 , 19 , 20 , 21 , 22 , 23 ], but also as catalytic label and as nanocarriers of signalling molecules.…”

“…A variety of uncoated MNPs are commercially available as well as MNPs modified with different coatings which minimize agglomeration, confer biocompatibility and allow modification with a wide variety of biomolecules, thus fueling the preparation of many biosensing designs. Among them, core-shell Fe 3 O 4 @Au [ 10 , 20 , 21 , 23 ] and Fe 3 O 4 @SiO 2 [ 18 , 22 ] MNPs have been profusely utilized. In the first type, the presence of gold nanoparticles provides good conductivity, improves the adsorption capacity of biomolecules and makes it possible to use thiolated derivatives to incorporate functionalities [ 20 ], while SiO 2 increases the stability of the nanoparticles providing a suitable surface for the binding of bioreactives [ 11 ].…”

“…Particular attention is given to the type of nanostructures and their role, target analyte, electrochemical technique and reported application. Although immunosensors and DNA sensors have been mostly prepared, aptasensors and others have been developed for the determination of: food allergens [ 18 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 ]; gluten [ 69 , 70 ]; GMOs [ 10 , 20 , 21 , 23 ]; toxins [ 32 , 71 , 72 ]; antibiotics [ 34 , 59 , 73 , 74 ]; pesticide residues [ 57 ]; bacteria [ 19 , 26 , 36 ]; fungus [ 22 , 75 ]; and yeast [ 76 ]. The biosensors were developed either in integrated formats or by coupling MNPs to conventional or screen-printed electrode substrates.…”

“…An illustrative example is the use of Fe 3 O 4 @Au MNPs modified with self-assembled monolayers (SAMs) of a mercaptoacid further modified covalently using carbodiimide/succinimide with aminated DNA capture probes to develop DNA sandwich hybridization strategies involving FITC or DIG modified-detector probes enzymatically labelled with HRP-conjugated Fab fragments [ 10 , 20 , 21 , 23 ]. By using amperometry in the presence of H 2 O 2 /HQ upon magnetic capturing of the modified MNPs onto SP(d)CEs or homemade AuEs, these methods exhibited a high sensitivity (pM-nM) for the determination of synthetic DNA fragments characteristic of transgenic maize and soybean.…”

Biosensing and Delivery of Nucleic Acids Involving Selected Well-Known and Rising Star Functional Nanomaterials

“…Among the magnetic nanomaterials, superparamagnetic iron oxide nanoparticles (MNPs), with diameters usually ranging between units and various tens of nanometers, have significantly impacted the biosensing of nucleic acids due to the great advantages they provide: large area, easy functionalization and communication with similarly sized biomacromolecules, peroxidase-like activity, rapid assay kinetics, improved sensitivity, matrix effect minimization and easy and effective control of their mobility by an external magnetic field [2,19,20,21,22,23,24,25]. In these biosensing approaches, MNPs can be used as transducer modifiers, as solid nanosupports to perform the affinity assay, which avoids complex and laborious protocols for modifying transducer surfaces [18,26,27,28,29,30], and as labels or nanocarriers of signaling molecules for signal amplification [31,32].…”