Real-Time Photoluminescent Biosensing Based on Graphene Oxide-Coated Microplates: A Rapid Pathogen Detection Platform

Abstract

Pathogenic bacterial contamination is a major threat to safety, human health, and ecosystems. Herein, we report an advantageous single-step, wash-free, and real-time bacterial detection platform operating with a single antibody. Escherichia coli was detected as a model analyte. This technology is based on graphene oxide-coated microplates (GOMs) and photoluminescent bioprobes (PLBs). On the one hand, using nonradiative energy transfer, GOMs are conceived to deactivate the photoluminescence of those PLBs that are not experimenting immunoreactions via antibody-bacterial membrane affinity. On the other hand, those PLBs experimenting immunoreactions preserve their photoluminescence because of both (i) the distance between the complex (PLBs-bacteria) and GOMs and (ii) the low affinity between the same complex and GOMs. With an optimal analytical performance of ∼30 min, the resulting bacterial detection platform was demonstrated to be fast and highly sensitive, exhibiting a limit of detection of ∼2 CFU mL–1. Industrial real samples were also successfully analyzed in a widely used format that is amenable to high-throughput applications. Moreover, the proposed technology is highly transformative, as graphene oxide is able to quench different fluorophores, and other analytes can be detected by simply changing the specific antibody.

Principles and Recent Advances in Biosensors for Pathogens Detection

“…Most optical transducers use enzymes that are immobilized on the sensing element to catalytically convert target biomolecules into products. [178][179] The use of biodegradable electrodes is one of the significant advantages of this optical transducer. An optical biosensor is a portable bioanalytical tool comprising a bio-receptor modified electrode coupled or integrated with an optical transducer element.…”

“…Recently, various types of optical biosensors have been used in the food industry for the rapid recognition of contaminants, toxins and pathogens. [178][179] These biosensors need an appropriate spectrometer to characterize the spectro- showing the lab-on-chip platform including a motherboard PCB that facilitates data readout, a cartridge PCB hosting the microchip and microfluidic chamber, the microchip including an array of 4096 ISFET sensors and an external thermal controller. Furthermore, a microphotograph showing a 6 × 6 subset of the ISFET array and (d) cross-section illustration of the lab-on-chip platform showing the reaction interface.…”

Graphene‐Based Nanomaterials for Biomedical, Catalytic, and Energy Applications

“…[54] One recent investigation, represented in Figure 4(B), by Mariana et al, reported the real-time bacterial biosensing platform based on the photoluminescence quenching property of graphene oxide coated microplates (GOMs). [55] A photoluminescent bioprobe (PLB) such as antibody-conjugated quantum dot was used in such a way that Escherichia coli model bacteria-interacting PLBs preserved their photoluminescence while the non-immunointeracting PLBs lose their photoluminescence. Distance between the PLB-Bacteria conjugate and GOMs, as well as the low affinity of the PLB-bacteria conjugate with GO, contributed to the observed fast and highly sensitive detection limit of ∼ 2 CFU ml À 1 .…”

“…Several mechanisms have been employed to enhance chemical reactivity of the graphene materials, either by defect engineering (increasing intrinsic defects, especially edge defects) or heteroatom doping (introducing boron, nitrogen, sulfur, etc. into the lattice [53] Copyright 2020, Elsevier Ltd. (B) Real-time bacterial biosensing platform based on GOMs using PLB conjugated quantum dots, Reproduced with permission, [55] Copyright 2020, American Chemical Society. (C) ZnO, Bi-metallic layer associated BaTiO 3 based SPR biosensor representation, with graphene top layer, Reproduced with permission, [57] Copyright 2020, Taylor & Francis Ltd. structure), which have recently been reviewed by Komeily-Nia et al.…”

“…Figure 4. Graphene-based biosensors; (A) Gold nanoparticle functionalized liquid gated, graphene field-effect transistor (G-FET) biosensor,[53] Copyright 2020, Elsevier Ltd. (B) Real-time bacterial biosensing platform based on GOMs using PLB conjugated quantum dots, Reproduced with permission,[55] Copyright 2020, American Chemical Society. (C) ZnO, Bi-metallic layer associated BaTiO 3 based SPR biosensor representation, with graphene top layer, Reproduced with permission,[57] Copyright 2020, Taylor & Francis Ltd.…”