Polymeric carbon nitride-based materials: Rising stars in bioimaging

Emerging Roles of Graphitic Carbon Nitride-based Materials in Biomedical Applications

Graphite carbon nitride (g-C3N4) is a two-dimensional conjugated polymer with a unique energy band structure similar to graphene. Due to its outstanding analytical advantages, such as relatively small band gap (2.7 eV), low-cost synthesis, high thermal stability, excellent photocatalytic ability, and good biocompatibility, g-C3N4 has attracted the interest of researchers and industry, especially in the medical field. This paper summarizes the latest research on g-C3N4-based composites in various biomedical applications, including therapy, diagnostic imaging, biosensors, antibacterial, and wearable devices. In addition, the application prospects and possible challenges of g-C3N4 in nanomedicine are also discussed in detail. This review is expected to inspire emerging biomedical applications based on g-C3N4.

Graphitic Carbon Nitride Enters the Scene: A Promising Versatile Tool for Biomedical Applications

Graphitic carbon nitride (g-C3N4), since the pioneering work on visible-light photocatalytic water splitting in 2009, has emerged as a highly promising advanced material for environmental and energetic applications, including photocatalytic degradation of pollutants, photocatalytic hydrogen generation, and carbon dioxide reduction. Due to its distinctive two-dimensional structure, excellent chemical stability, and distinctive optical and electrical properties, g-C3N4 has garnered a considerable amount of interest in the field of biomedicine in recent years. This review focuses on the fundamental properties of g-C3N4, highlighting the synthesis and modification strategies associated with the interfacial structures of g-C3N4-based materials, including heterojunction, band gap engineering, doping, and nanocomposite hybridization. Furthermore, the biomedical applications of these materials in various domains, including biosensors, antimicrobial applications, and photocatalytic degradation of medical pollutants, are also described with the objective of spotlighting the unique advantages of g-C3N4. A summary of the challenges faced and future prospects for the advancement of g-C3N4-based materials is presented, and it is hoped that this review will inspire readers to seek further new applications for this material in biomedical and other fields.

Nanoengineered phosphorus doped graphitic carbon nitride based ultrasensitive biosensing platform for Swine flu detection

In the present study, we developed an amino-polyindole modified phosphorus doped graphitic carbon nitride nanomaterial (APIN/P-g-C3N4) based immunosensing biochip for Serum amyloid A (SAA) biomarker towards early diagnosis of Swine flu. The P-g-C3N4 was synthesis via polycondensation and functionalized with APIN. Further, the biochip was fabricated by modifying the working area of SPE with APIN/P-g-C3N4 using drop cast method, APIN introduced the larger loading of -NH2 group moieties onto P-g-C3N4 matrix and benefitted to reinforced the biomolecules via covalent linkages. The monoclonal anti-SAA was conjugated onto APIN/P-g-C3N4/SPE using EDC-NHS chemistry and BSA was added for non-specific site blocking. The structural, chemical, composition and morphological characteristics of the synthesized, functionalized nanomaterial and fabricated biochips were investigated by XRD, XPS, FT-IR spectroscopy, SEM, FE-SEM and TEM techniques. Further, the electrochemical characterization and response studies of fabricated biochip were analyzed using the CV and DPV techniques. Based on the analytical performance of the proposed immunosensing biochip i.e. BSA/anti-SAA/APIN/P-g-C3N4/SPE, it is capable to detect SAA protein with ultra sensitivity of 79.5 μA log (mL ng-1) cm-2, ultralow limit of detection of 5 ng mL-1 and wider linear detection range of 5 ng mL-1-500 μg mL-1 with quick response time of 10 min. Moreover, the fabricated immunosensing biochips was used to analyse SAA protein in spiked serum samples and the achieved results demonstrated the good agreement with the electrochemical response observed in standard SAA protein samples in analytical solution. The proposed biochip can provide insights for developing a wide range of clinical screening tools for detecting various contagious diseases.

Strategies for Improving the Photocatalytic Hydrogen Evolution Reaction of Carbon Nitride-Based Catalysts

Due to the depletion of fossil fuels and their-related environmental issues, sustainable, clean, and renewable energy is urgently needed to replace fossil fuel as the primary energy resource. Hydrogen is considered as one of the cleanest energies. Among the approaches to hydrogen production, photocatalysis is the most sustainable and renewable solar energy technique. Considering the low cost of fabrication, earth abundance, appropriate bandgap, and high performance, carbon nitride has attracted extensive attention as the catalyst for photocatalytic hydrogen production in the last two decades. In this review, the carbon nitride-based photocatalytic hydrogen production system, including the catalytic mechanism and the strategies for improving the photocatalytic performance is discussed. According to the photocatalytic processes, the strengthened mechanism of carbon nitride-based catalysts is particularly described in terms of boosting the excitation of electrons and holes, suppressing carriers recombination, and enhancing the utilization efficiency of photon-excited electron-hole. Finally, the current trends related to the screening design of superior photocatalytic hydrogen production systems are outlined, and the development direction of carbon nitride for hydrogen production is clarified.

Effect of Functional Group Modifications on the Photocatalytic Performance of g-C3 N4

In recent years, photocatalysis has received increasing attention in alleviating energy scarcity and environmental treatment, and graphite carbon nitride (g-C₃ N₄ ) is used as an ideal photocatalyst. However, it still remains numerous challenges to obtain the desirable photocatalytic performance of intrinsic g-C₃ N₄ . Functional group functionalization, formed by introducing functional groups into the bulk structure, is one of the common modification techniques to modulate the carrier dynamics and increases the number of active sites, offering new opportunities to break the limits for structure-to-performance relationship of g-C₃ N₄ . Nevertheless, the general overview of the advance of functional group modification of g-C₃ N₄ is less reported yet. In order to better understand the structure-to-performance relationship at the molecular level, a review of the latest development of functional group modification is urgently needed. In this review, the functional group modification of g-C₃ N₄ in terms of structures, properties, and photocatalytic activity is mainly focused, as well as their mechanism of reaction from the molecular level insights is explained. Second, the recent progress of the application of introducing functional groups in g-C₃ N₄ is introduced and examples are given. Finally, the difficulties and challenges are presented, and based on this, an outlook on the future research development direction is shown.

Emerging Polymer Materials in Trackable Endovascular Embolization and Cell Delivery: From Hype to Hope

Minimally invasive endovascular embolization is a widely used clinical technique used for the occlusion of blood vessels to treat various diseases. Different occlusive agents ranging from gelatin foam to synthetic polymers such as poly(vinyl alcohol) (PVA) have been commercially used for embolization. However, these agents have some drawbacks, such as undesired toxicity and unintended and uncontrolled occlusion. To overcome these issues, several polymer-based embolic systems are under investigation including biocompatible and biodegradable microspheres, gelling liquid embolic with controlled occlusive features, and trackable microspheres with enhanced safety profiles. This review aims to summarize recent advances in current and emerging polymeric materials as embolization agents with varying material architectures. Furthermore, this review also explores the potential of combining injectable embolic agents and cell therapy to achieve more effective embolization with the promise of outstanding results in treating various devastating diseases. Finally, limitations and challenges in developing next-generation multifunctional embolic agents are discussed to promote advancement in this emerging field.