Air-brush spray coated Ti3C2-MXene-graphene nanohybrid thin film based electrochemical biosensor for cancer biomarker detection

L-Cysteine functionalized magnetite nanoparticle adorned Ti3C2-MXene nanohybrid based screen printed immunosensor for oral cancer biomarker detection

Nanohybrid based non-invasive biosensing platforms are emerging as promising alternatives to detect biomarkers in complex and diverse bio-fluids toward ultrasensitive point-of-care diagnostics. Herein, we report the development of a highly sensitive, facile, non-invasive, label free, affordable, and innovative electrochemical screen printed immunosensor for identifying CYFRA 21-1, an established and crucial biomarker for oral cancer. Until now, no work has been reported utilizing a titanium carbide Ti3C2 MXene nanosheet and L-cysteine (L-Cyst) functionalized magnetite nanoparticle (MNPs) nanohybrid based immunosensor for electrochemical detection of CYFRA 21-1. The L-Cyst@MNPs/Ti3C2-MXene nanohybrid was synthesized via the co-precipitation method and later deposited on a gold screen printed electrode (GSPE) offering enhanced surface area and electrochemical properties. The nanohybrid modified GSPE was then surface immobilized with monoclonal antibodies (anti-CYFRA-21-1) to fabricate an anti-CYFRA-21-1/L-Cyst@MNPs/Ti3C2-MXene/GSPE immunoelectrode and the non-specific locations of the immunoelectrode were covered with bovine serum albumin (BSA). The spectroscopic, morphological, and structural analyses of the synthesized nanohybrid and the fabricated electrodes were performed using different analytical techniques. The electrochemical studies of modified electrodes were evaluated using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV). The fabricated BSA/anti-CYFRA-21-1/L-Cyst@MNPs/Ti3C2-MXene/GSPE immunosensor has shown an excellent limit of detection of 0.023 ng mL-1, a linear detection range of (0.5-30) ng mL-1, a sensitivity of 277.28 μA (ng mL-1)-1 cm-2 and a lower limit of quantification of 0.618 ng mL-1 for electrochemical CYFRA 21-1 determination. Hence, this L-Cyst@MNPs/Ti3C2-MXene nanohybrid could also be explored as a potential candidate for determining other cancer biomarkers.

Multimodal Biosensing of Foodborne Pathogens

Microbial foodborne pathogens present significant challenges to public health and the food industry, requiring rapid and accurate detection methods to prevent infections and ensure food safety. Conventional single biosensing techniques often exhibit limitations in terms of sensitivity, specificity, and rapidity. In response, there has been a growing interest in multimodal biosensing approaches that combine multiple sensing techniques to enhance the efficacy, accuracy, and precision in detecting these pathogens. This review investigates the current state of multimodal biosensing technologies and their potential applications within the food industry. Various multimodal biosensing platforms, such as opto-electrochemical, optical nanomaterial, multiple nanomaterial-based systems, hybrid biosensing microfluidics, and microfabrication techniques are discussed. The review provides an in-depth analysis of the advantages, challenges, and future prospects of multimodal biosensing for foodborne pathogens, emphasizing its transformative potential for food safety and public health. This comprehensive analysis aims to contribute to the development of innovative strategies for combating foodborne infections and ensuring the reliability of the global food supply chain.

MXene-based electrochemical devices applied for healthcare applications

The initial part of the review provides an extensive overview about MXenes as novel and exciting 2D nanomaterials describing their basic physico-chemical features, methods of their synthesis, and possible interfacial modifications and techniques, which could be applied to the characterization of MXenes. Unique physico-chemical parameters of MXenes make them attractive for many practical applications, which are shortly discussed. Use of MXenes for healthcare applications is a hot scientific discipline which is discussed in detail. The article focuses on determination of low molecular weight analytes (metabolites), high molecular weight analytes (DNA/RNA and proteins), or even cells, exosomes, and viruses detected using electrochemical sensors and biosensors. Separate chapters are provided to show the potential of MXene-based devices for determination of cancer biomarkers and as wearable sensors and biosensors for monitoring of a wide range of human activities.