An ultrasensitive heart-failure BNP biosensor using B/N co-doped graphene oxide gel FET

Biosensors for natriuretic peptides in cardiovascular diseases. A review

Heart failure (HF) is a complex clinical syndrome associated with high rates of morbidity and mortality. Over the years, it has been crucial to find accurate biomarkers capable of doing a precise monitor of HF and provide an early diagnosis. Of these, it has been established an important role of natriuretic peptides in HF assessment. Moreover, the development of biosensors has been garnering interest as new diagnostic medical tools. In this review we first provide a general overview of HF, its pathogenesis, and diagnostic features. We then discuss the role of natriuretic peptides in heart failure by characterizing them and point out their potential as biomarkers. Finally, we adress the evolution of biosensors development and the available natriuretic peptides biosensors for disease monitoring.

Recent advances in the peptide-based biosensor designs

Biosensors have rapidly emerged as a high-sensitivity and convenient detection method. Among various types of biosensors, optical and electrochemical are the most commonly used. Conventionally, antibodies have been employed to ensure specific interaction between the transmission material and analytes. However, there has been increasing recognition of peptides as a promising recognition element for biosensor development in recent years. The use of peptides as recognition elements provides high level of specificity, sensitivity, and stability for the detection process. The combination of peptide designs and optical or electrochemical detection methods has significantly improved biosensor efficacy. These advancements present opportunities for developing biosensors with diverse functions that can be used to lay a strong scientific foundation for the development of personalized medicine and various other fields. This paper reviews the recent advancements in the development and application of peptide-based optical and electrochemical biosensors, as well as their prospects as a sensor type.

Review on two-dimensional material-based field-effect transistor biosensors: accomplishments, mechanisms, and perspectives

Field-effect transistor (FET) is regarded as the most promising candidate for the next-generation biosensor, benefiting from the advantages of label-free, easy operation, low cost, easy integration, and direct detection of biomarkers in liquid environments. With the burgeoning advances in nanotechnology and biotechnology, researchers are trying to improve the sensitivity of FET biosensors and broaden their application scenarios from multiple strategies. In order to enable researchers to understand and apply FET biosensors deeply, focusing on the multidisciplinary technical details, the iteration and evolution of FET biosensors are reviewed from exploring the sensing mechanism in detecting biomolecules (research direction 1), the response signal type (research direction 2), the sensing performance optimization (research direction 3), and the integration strategy (research direction 4). Aiming at each research direction, forward perspectives and dialectical evaluations are summarized to enlighten rewarding investigations.

Recent advances of graphene-biomacromolecule nanocomposites in medical applications

In recent years, graphene-based composites have received increasing attention due to their high biocompatibility, large specific surface area, high electrical conductivity and unique mechanical properties. The combination of biomacromolecules and graphene provides a promising route for the preparation of novel graphene-based nanocomposites. Novel graphene-based nanocomposites with unique functions could be applied to medicine, biology, biosensors, environmental science, energy storage and other fields. Graphene-biomacromolecule nanocomposites have excellent biocompatibility, outstanding biofunctionality and low cytotoxicity, and have more advantages and development prospects than other traditional graphene-based materials in biological and biomedical fields. In this work, we summarize the research on the covalent and non-covalent interactions between different biomacromolecules (peptides, DNA/RNA, proteins and enzymes) and graphene, as well as the synthesis methods of novel functionalized graphene-biomacromolecule composites in recent years. We mainly introduce the recent advances (last 5 years) of graphene-biomacromolecule nanocomposites in medical applications, such as medical detection and disease treatment. We hope that this review will help readers to understand the methods and mechanisms of biomolecules modifying the surface of graphene, as well as the synthesis and application of graphene-based nanocomposites, which will promote the future developments of graphene-biomolecule composites in biomedicine, tissue engineering, materials engineering, and so on.

Electronic field effect detection of SARS-CoV-2 N-protein before the onset of symptoms

As part of the efforts to contain the pandemic, researchers around the world have raced to develop testing platforms to detect the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes the Coronavirus disease 2019 (COVID-19). Within the different detection platforms studied, the field effect transistor (FET) is a promising device due to its high sensitivity and fast detection capabilities. In this work, a graphene-based FET which uses a boron and nitrogen co-doped graphene oxide gel (BN-GO gel) transducer functionalized with nucleoprotein antibodies, has been investigated for the detection of SARS-CoV-2 nucleocapsid (N)-protein in buffer. This biosensor was able to detect the viral protein in less than 4 min, with a limit of detection (LOD) as low as 10 ag/mL and a wide linear detection range stretching over 11 orders of magnitude from 10 ag/mL-1 μg/mL. This represents the lowest LOD and widest detection range of any COVID-19 sensor and thus can potentially enable the detection of infected individuals before they become contagious. In addition to its potential use in the COVID-19 pandemic, our device serves as a proof-of-concept of the ability of functionalized BN-GO gel FETs to be used for ultrasensitive yet robust biosensors.

Graphene-Based Biosensors for Molecular Chronic Inflammatory Disease Biomarker Detection

Chronic inflammatory diseases, such as cancer, diabetes mellitus, stroke, ischemic heart diseases, neurodegenerative conditions, and COVID-19 have had a high number of deaths worldwide in recent years. The accurate detection of the biomarkers for chronic inflammatory diseases can significantly improve diagnosis, as well as therapy and clinical care in patients. Graphene derivative materials (GDMs), such as pristine graphene (G), graphene oxide (GO), and reduced graphene oxide (rGO), have shown tremendous benefits for biosensing and in the development of novel biosensor devices. GDMs exhibit excellent chemical, electrical and mechanical properties, good biocompatibility, and the facility of surface modification for biomolecular recognition, opening new opportunities for simple, accurate, and sensitive detection of biomarkers. This review shows the recent advances, properties, and potentialities of GDMs for developing robust biosensors. We show the main electrochemical and optical-sensing methods based on GDMs, as well as their design and manufacture in order to integrate them into robust, wearable, remote, and smart biosensors devices. We also describe the current application of such methods and technologies for the biosensing of chronic disease biomarkers. We also describe the current application of such methods and technologies for the biosensing of chronic disease biomarkers with improved sensitivity, reaching limits of detection from the nano to atto range concentration.

Two-Dimensional Field-Effect Transistor Sensors: The Road toward Commercialization

The evolutionary success in information technology has been sustained by the rapid growth of sensor technology. Recently, advances in sensor technology have promoted the ambitious requirement to build intelligent systems that can be controlled by external stimuli along with independent operation, adaptivity, and low energy expenditure. Among various sensing techniques, field-effect transistors (FETs) with channels made of two-dimensional (2D) materials attract increasing attention for advantages such as label-free detection, fast response, easy operation, and capability of integration. With atomic thickness, 2D materials restrict the carrier flow within the material surface and expose it directly to the external environment, leading to efficient signal acquisition and conversion. This review summarizes the latest advances of 2D-materials-based FET (2D FET) sensors in a comprehensive manner that contains the material, operating principles, fabrication technologies, proof-of-concept applications, and prototypes. First, a brief description of the background and fundamentals is provided. The subsequent contents summarize physical, chemical, and biological 2D FET sensors and their applications. Then, we highlight the challenges of their commercialization and discuss corresponding solution techniques. The following section presents a systematic survey of recent progress in developing commercial prototypes. Lastly, we summarize the long-standing efforts and prospective future development of 2D FET-based sensing systems toward commercialization.

Multifunctional carbon nanomaterials for diagnostic applications in infectious diseases and tumors

Infectious diseases (such as Corona Virus Disease 2019) and tumors pose a tremendous challenge to global public health. Early diagnosis of infectious diseases and tumors can lead to effective control and early intervention of the patient's condition. Over the past few decades, carbon nanomaterials (CNs) have attracted widespread attention in different scientific disciplines. In the field of biomedicine, carbon nanotubes, graphene, carbon quantum dots and fullerenes have the ability of improving the accuracy of the diagnosis by the improvement of the diagnostic approaches. Therefore, this review highlights their applications in the diagnosis of infectious diseases and tumors over the past five years. Recent advances in the field of biosensing, bioimaging, and nucleic acid amplification by such CNs are introduced and discussed, emphasizing the importance of their unique properties in infectious disease and tumor diagnosis and the challenges and opportunities that exist for future clinical applications. Although the application of CNs in the diagnosis of several diseases is still at a beginning stage, biosensors, bioimaging technologies and nucleic acid amplification technologies built on CNs represent a new generation of promising diagnostic tools that further support their potential application in infectious disease and tumor diagnosis.

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Carbon nanomaterials (CNs) are systematically introduced in this review.

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This review studies the application of CNs in infectious diseases and tumors diagnosis.

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CNs act as potent nanostructures for biosensing, bioimaging, & nucleic acid amplification.

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New CN-based detection methods were introduced to detect SARS-CoV-2.

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The challenges and prospects of CN-based diagnostic assays are also discussed.

Efficacy of graphene oxide-loaded cationic antimicrobial peptide AWRK6 on the neutralization of endotoxin activity and in the treatment of sepsis

Objective: This study is to assess the therapeutic effect of graphene oxide (GO) loaded with AWRK6 on endotoxin-induced sepsis.

Method: AWRK6/GO was prepared by GO loaded AWRK6, with the structure characterization of AWRK6/GO conducted by atomic force microscope (AFM) and ultraviolet spectrophotometer, the sustained release rate of AWRK6/GO detected by high performance liquid chromatography (HPLC), and the neutralization ability of AWRK6/GO to lipopolysaccharide (LPS) tested by in vitro experiments. The levels of IL-8 and TNF-α in mouse cells after drug intervention were detected by ELISA; a LPS mouse model was established to observe the effects of drug intervention on the survival cycle and survival rate of mice.

Results: The sustained drug release rate of AWRK6/GO reached 85% within 24 hours observed under in vitro conditions, with an efficient neutralization effect to LPS (P < 0.01); Compared with the control group, the intervention of LPS succeeded in remarkably elevating the levels of IL-8 and TNF-α in the whole blood and macrophages of the mice (P < 0.01), whose survival cycle and survival rate consequently observed an obvious decline (P < 0.01); The intervention with AWRK6 or AWRK6/GO predominantly brought down the levels of IL-8 and TNF-α in the whole blood and macrophages of mice given LPS (P < 0.01), resulting in an elevation of the survival rate and survival time (P < 0.01).

Conclusion: GO loaded with cationic antimicrobial peptide AWRK6 exerts a rosy neutralization effect on endotoxin activity, with no obvious side effects on mice observed, which is of certain application value in the treatment of sepsis.

A handheld testing device for the fast and ultrasensitive recognition of cardiac troponin I via an ion-sensitive field-effect transistor

Cardiac troponin I (cTnI) is an efficient and specific biomarker for the accurate diagnosis of acute myocardial infarction (AMI), one of the diseases with the highest mortality worldwide. Due to the short course and high fatality of this disease, a rapid, accurate and portable device for quantitative detection is urgently needed for early diagnosis and treatment. In this work, we designed a handheld device based on a dual-gate ion-sensitive field-effect transistor (ISFET) for early and accurate warning of AMI through cTnI detection. A one-step enzyme-linked immunosorbent assay strategy was proposed for use in this device to recognize trace cTnI in serum, converting the cTnI concentration to a drain-source current generated by an ultrasensitive ISFET. This portable device exhibited an ultrahigh sensitivity of 132 pA pg^-1·mL^-1, a wide linear range from 1 to 1000 pg/mL that enabled coverage far exceeding the threshold level (280 pg/mL), and a low detection limit of 0.3 pg/mL for the cTnI assay, which was much lower than the current diagnostic cut-off for a healthy control level for AMI (40 pg/mL). In addition, this handheld device showed satisfactory selectivity and reliable results in the analysis of real serum within 20 min, indicating its potential applications in early screening and diagnosis for the clinical evaluation of AMI.