Fabrication of a Molecularly Imprinted Nano-Interface-Based Electrochemical Biosensor for the Detection of CagA Virulence Factors of H. pylori

Abstract

H. pylori is responsible for several stomach-related diseases including gastric cancer. The main virulence factor responsible for its establishment in human gastric cells is known as CagA. Therefore, in this study, we have fabricated a highly sensitive MIP-based electrochemical biosensor for the detection of CagA. For this, an rGO and gold-coated, screen-printed electrode sensing platform was designed to provide a surface for the immobilization of a CagA-specific, molecularly imprinted polymer; then it was characterized electrochemically. Interestingly, molecular dynamics simulations were studied to optimize the MIP prepolymerization system, resulting in a well-matched, optimized molar ratio within the experiment. A low binding energy upon template removal indicates the capability of MIP to recognize the CagA antigen through a strong binding affinity. Under the optimized electrochemical experimental conditions, the fabricated CagA-MIP/Au/rGO@SPE sensor exhibited high sensitivity (0.275 µA ng−1 mL−1) and a very low limit of detection (0.05 ng mL−1) in a linear range of 0.05–50 ng mL−1. The influence of other possible interferents in analytical response has also been observed with the successful determination of the CagA antigen.

Molecularly Imprinted Polymer-Based Biomimetic Systems for Sensing Environmental Contaminants, Biomarkers, and Bioimaging Applications

“…were obtained for real saliva glucose determination compared with a finger prick blood sample (Figure 12) [178]. Electro polymerization EIS SARS-CoV-2 10 to 10 8 PFU/mL Saliva-(98 to 104%) [190] Free radical polymerization vinyl phosphonic acid sarcosine 0.04 µM [191] One pot method DPV Creatinine 2 × 10 −2 pg/mL Serum, urine (93.7-109.2%) [192] Methyl methacrylate DPV H. pylori 0.05 ng mL −1 Blood-96% [193] Electro polymerization 2-aminophenol EIS Galectin-3 30 ng/mL [194] Electro Electro polymerization 3-aminophenylboronic acid CV and EIS Interleukin-6 1 pg/mL [179] From these studies, MIPs-based sensors could provide many advantages, such as costeffectiveness, superior stability, rapid, easy synthesis, selectivity, and high sensitivity, which can be utilized for biomedical applications. Apart from all these advantages, one of the main limitations of MIPs is the hydrophobic or hydrophilic nature the monomer, which influences polymer imprinting.…”

Immunosensors for Assay of Toxic Biological Warfare Agents

“…The affinity of the surface to the target molecule is based on the shape and molecular interactions, which are not guaranteed when a homogenous membrane is used, and testing small molecules with defined physical and chemical specifications is an easier task for sensors with molecularly imprinted polymers. Experiences with molecularly imprinted polymers for the preparation of sensors include the Helicobacter pylori virulence factor assay [ 57 ], specific extraction of aflatoxins by molecularly imprinted polymers [ 58 ], and the human immunodeficiency virus drug assay by Tenofovir [ 59 ]. The use of molecularly imprinted polymer will gain more applications when new materials are developed as a platform for in situ membrane manufacturing.…”

Reduced Graphene Oxide Nanosheets Enhance the Sensitivity of p-Cresyl Sulfate Detection Using a Molecularly Imprinted Polymer-Based Electrochemical Sensor

“…Also, the large surface area of the regular rGO nanostructure helps improve movement of the active redox species, eventually enhancing the sensitivity of PMAA@rGO-MIP-based sensors. 23 Additionally, superior surface area provides an immense active center for anchoring electrolytes at the electrode interface. 24 Apart from these properties, rGO also shows biocompatibility and a high chemical stability, which make it an ideal candidate for electrochemical sensing.…”

“…Due to these properties, rGO gives enhanced sensitivity, which helps in sensing low concentrations of analytes. Also, the large surface area of the regular rGO nanostructure helps improve movement of the active redox species, eventually enhancing the sensitivity of PMAA@rGO-MIP-based sensors . Additionally, superior surface area provides an immense active center for anchoring electrolytes at the electrode interface .…”