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Early diagnosis of cancer can be achieved by detecting associated biomarkers before the appearance of symptoms. Herein, we have developed an electrochemical immunosensor of ionic liquid tailored to molybdenum trioxide‐reduced graphene oxide (MoO3‐rGO‐IL) nanocomposite to detect carcinoembryonic antigen (CEA), a cancer biomarker. The MoO3‐rGO‐IL nanocomposite has been synthesized in situ via the hydrothermal method. The functionalization of 1‐butyl‐3‐methylimidazolium tetrafluoroborate IL with MoO3‐rGO synergistically improves the electrochemical and surface properties of the nanocomposite. The characterization studies revealed that the MoO3‐rGO‐IL nanocomposite is a highly appropriate material for the construction of immunosensors. The material exhibits exceptional electrical conductivity, surface properties, stability, and a large electrochemical effective surface area (13.77×10−2 cm2) making it ideal for fabricating immunosensors. The quantitative outcome showed that the developed immunosensor (BSA/anti‐CEA/MoO3‐rGO‐IL/GCE) possesses excellent sensitivity, broad linearity from 25 fg mL−1 to 100 ng mL−1, and a low detection limit of 1.19 fg mL−1. Moreover, the remarkable selectivity, repeatability, and efficiency of detecting CEA in serum specimens demonstrated the feasibility of the immunosensor. Thus, the projected electrochemical immunosensor can potentially be utilized for the quantification of CEA in clinical specimens. [ABSTRACT FROM AUTHOR]

Microbial pathogens have threatened the world due to their pathogenicity and ability to spread in communities. The conventional laboratory‐based diagnostics of microbes such as bacteria and viruses need bulky expensive experimental instruments and skilled personnel which limits their usage in resource‐limited settings. The biosensors‐based point‐of‐care (POC) diagnostics have shown huge potential to detect microbial pathogens in a faster, cost‐effective, and user‐friendly manner. The use of various transducers such as electrochemical and optical along with microfluidic integrated biosensors further enhances the sensitivity and selectivity of detection. Additionally, microfluidic‐based biosensors offer the advantages of multiplexed detection of analyte and the ability to deal with nanoliters volume of fluid in an integrated portable platform. In the present review, we discussed the design and fabrication of POCT devices for the detection of microbial pathogens which include bacteria, viruses, fungi, and parasites. The electrochemical techniques and current advances in this field in terms of integrated electrochemical platforms that include mainly microfluidic‐ based approaches and smartphone and Internet‐of‐things (IoT) and Internet‐of‐Medical‐Things (IoMT) integrated systems have been highlighted. Further, the availability of commercial biosensors for the detection of microbial pathogens will be briefed. In the end, the challenges while fabrication of POC biosensors and expected future advances in the field of biosensing have been discussed. The integrated biosensor‐based platforms with the IoT/IoMT usually collect the data to track the community spread of infectious diseases which would be beneficial in terms of better preparedness for current and futuristic pandemics and is expected to prevent social and economic losses. [ABSTRACT FROM AUTHOR]

The outbreak of the highly contagious disease COVID-19, which is triggered by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), demands a rapid, low-cost, and highly sensitive immunosensor that can detect and identify the virus efficiently. Here, an electrochemical immunosensor based on a nanocomposite consisting of molybdenum disulfide nanosheets decorated with polydopamine (MoS2-PDA) is developed for highly sensitive detection of SARS-CoV-2 nucleocapsid protein (N protein). The MoS2-PDA nanocomposite possesses various hydroxyl and amine groups that have excellent chemistry with crosslinkers and act as adhesive agents to bind with the working electrode surface. Furthermore, the optical, functional, structural, vibrational, and morphological properties of the MoS2-PDA nanocomposite are studied using various characterization techniques such as UV-vis, FTIR, and Raman spectroscopies, XRD, and TEM. The electrochemical immunosensor is fabricated by functionalizing the MoS2-PDA nanocomposite with anti-SARS-CoV-2 nucleocapsid IgG antibody (Ab) and has a very high sensitivity against the N protein with a linear range between 10 ag mL−1 and 100 ng mL−1. The electrochemical immunosensor exhibits a lowest limit of detection (LOD) of 2.80 ag mL−1 and a limit of quantification (LOQ) of 8.48 ag mL−1via electrochemical impedance spectroscopy (EIS). Furthermore, the electrochemical immunosensor is successfully employed to detect the N protein in nasopharyngeal swab specimens and displays good consistency with the conventional RT-PCR test results. The results show that the MoS2-PDA nanocomposite-based electrochemical platform can serve as a highly sensitive and selective detector of N protein and will pave the way for the development of a point-of-care (POC) electrochemical immunosensor for rapid detection of other infectious viruses. [ABSTRACT FROM AUTHOR]

Herein, we develop an electrochemical immunosensor based on a zirconia-reduced graphene oxide-1-ethyl-3-methylimidazolium tetrafluoroborate (EMIM.BF4) ionic liquid (ZrO2-rGO-IL) nanocomposite for the detection of a carcinoembryonic antigen (CEA) breast cancer biomarker. The characterization results of the synthesized ZrO2-rGO-IL nanocomposite show that it has high electroconductivity, oxygen functionalities, and a larger active surface area, which favors high loading of anti-CEA antibodies. The fabricated BSA/anti-CEA/ZrO2-rGO-IL/GCE immunosensor can detect CEA with high sensitivity and selectivity in a broad detection range between 25.0 fg mL–1 and 25.0 ng mL–1 with an ultralow limit of detection (LOD) of 1.23 fg mL–1 through differential pulse voltammetry (DPV). In addition, we tested the CEA in serum samples having linear detection ranges from 100.0 fg mL–1 to 5.0 ng mL–1 with an LOD of 2.25 fg mL–1. Subsequently, the incubation time and selectivity of the immunosensor show a great affinity for CEA. Therefore, the proposed immunosensor can be a promising candidate for CEA detection in clinical specimens. Prospectively, the synthesized nanocomposite will have the potential for the effective detection of other cancer biomarkers. [ABSTRACT FROM AUTHOR]

Recently, two-dimensional (2D)-borophene has emerged as a remarkable translational nanomaterial substituting its predecessors in the field of biomedical sensors, diagnostic tools, high-performance healthcare devices, super-capacitors, and energy storage devices. Borophene justifies its demand due to high-performance and controlled optical, electrical, mechanical, thermal, and magnetic properties as compared with other 2D-nanomaterials. However, continuous efforts are being made to translate theoretical and experimental knowledge into pragmatic platforms. To cover the associated knowledge gap, this review explores the computational and experimental chemistry needed to optimize borophene with desired properties. High electrical conductivity due to destabilization of the highest occupied molecular orbital (HOMO), nano-engineering at the monolayer level, chemistry-oriented biocompatibility, and photo-induced features project borophene for biosensing, bioimaging, cancer treatment, and theragnostic applications. Besides, the polymorphs of borophene have been useful to develop specific bonding for DNA sequencing and high-performance medical equipment. In this review, an overall critical and careful discussion of systematic advancements in borophene-based futuristic biomedical applications including artificial intelligence (AI), Internet-of-Things (IoT), and Internet-of-Medical Things (IoMT) assisted smart devices in healthcare to develop high-performance biomedical systems along with challenges and prospects is extensively addressed. Consequently, this review will serve as a key supportive platform as it explores borophene for next-generation biomedical applications. Finally, we have proposed the potential use of borophene in healthcare management strategies. [ABSTRACT FROM AUTHOR]

Despite significant accomplishments in developing efficient rapid sensing systems and nano-therapeutics of higher efficacy, the recent coronavirus disease (COVID-19) pandemic is not under control successfully because the severe acute respiratory syndrome virus (SARS-CoV-2, original and mutated) transmits easily from human to -human and causes life-threatening respiratory disorders. Thus, it has become crucial to avoid this transmission through precautions and keep premises hygienic using high-performance anti-viral nanomaterials to trap and eradicate SARS-CoV-2. Such an antiviral nano-system has successfully demonstrated useful significant contribution in COVID-19 pandemic/endemic management effectively. However, their projection with potential sustainable prospects still requires considerable attention and efforts. With this aim, the presented review highlights various severe life-threatening viral infections and the role of multi-functional anti-viral nanostructures with manipulative properties investigated as an efficient precative shielding agent against viral infection progression. The salient features of such various nanostructures, antiviral mechanisms, and high impact multi-dimensional roles are systematically discussed in this review. Additionally, the challenges associated with the projection of alternative approaches also support the demand and significance of this selected scientific topic. The outcomes of this review will certainly be useful to motivate scholars of various expertise who are planning future research in the field of investigating sustainable and affordable high-performance nano-systems of desired antiviral performance to manage not only COVID-19 infection but other targeted viral infections as well. [ABSTRACT FROM AUTHOR]

Coronavirus disease (COVID-19) is an emerging and highly infectious disease making global public health concern and socio-economic burden. It is caused due to Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2). It has the tendency to spread rapidly through person-to-person. Currently, several molecular diagnostic platforms such as PCR, qRT-PCR, reverse transcription loop-mediated isothermal amplification (RT-LAMP), CRISPR are utilized for the diagnosis of SARS-CoV-2. These conventional techniques are costly, time consuming and require sophisticated instrumentation facility with well trained personnel for testing. Hence, it is tough to provide testing en-masse to the people in developing countries. On the other hand, several serological biosensors such as lateral flow immunosensor, optical, electrochemical, microfluidics integrated electrochemical/fluorescence is currently utilized for the diagnosis of SARS-CoV-2. In current pandemic situation, there is an urgent need of rapid and efficient diagnosis on mass scale of SARS-CoV-2 for early stage detection. Early monitoring of viral infections can help to control and prevent the spreading of infections in large chunk of population. In this review, the SARS-CoV-2 and their biomarkers in biological samples, collection of samples and recently reported potential electrochemical immunosensors for the rapid diagnosis of SARS-CoV-2 are discussed. [ABSTRACT FROM AUTHOR]

Ionic liquids are gaining high attention due to their extremely unique physiochemical properties and are being utilized in numerous applications in the field of electrochemistry and bio-nanotechnology. The excellent ionic conductivity and the wide electrochemical window open a new avenue in the construction of electrochemical devices. On the other hand, carbon nanomaterials, such as graphene (GR), graphene oxide (GO), carbon dots (CDs), and carbon nanotubes (CNTs), are highly utilized in electrochemical applications. Since they have a large surface area, high conductivity, stability, and functionality, they are promising in biosensor applications. Nevertheless, the combination of ionic liquids (ILs) and carbon nanomaterials (CNMs) results in the functional ILs-CNMs hybrid nanocomposites with considerably improved surface chemistry and electrochemical properties. Moreover, the high functionality and biocompatibility of ILs favor the high loading of biomolecules on the electrode surface. They extremely enhance the sensitivity of the biosensor that reaches the ability of ultra-low detection limit. This review aims to provide the studies of the synthesis, properties, and bonding of functional ILs-CNMs. Further, their electrochemical sensors and biosensor applications for the detection of numerous analytes are also discussed. [ABSTRACT FROM AUTHOR]