Influence of Nitrogen-Doped Carbon Dot and Silver Nanoparticle Modified Carbon Paste Electrodes on the Potentiometric Determination of Tobramycin Sulfate: A Comparative Study

Two inexpensive and simple methods for synthesis of carbon nanodots were applied and compared to each other, namely a hydrothermal and microwave-assisted method. The synthesized carbon nanodots were characterized using transmission electron microscopy (TEM), ultraviolet-visible (UV-Vis), photoluminescence (PL), Fourier transform-infrared spectroscopy (FTIR), and X-ray diffraction (XRD). The synthesized microwave carbon nanodots had smaller particle size and were thus chosen for better electrochemical performance. Therefore, they were used for our modification process. The proposed electrodes performance characteristics were evaluated according to the IUPAC guidelines, showing linear response in the concentration range 10−6–10−2, 10−7–10−2, and 10−8–10−2 M of tobramycin with a Nernstian slope of 52.60, 58.34, and 57.32 mV/decade for the bare, silver nanoparticle and carbon nanodots modified carbon paste electrodes, respectively. This developed potentiometric method was used for quantification of tobramycin in its co-formulated dosage form and spiked human plasma with good recovery percentages and without interference of the co-formulated drug loteprednol etabonate and excipients.

Ultrasmall and highly biocompatible carbon dots derived from natural plant with amelioration against acute kidney injury.

BACKGROUND: Acute kidney injury (AKI) refers to a tricky clinical disease, known by its high morbidity and mortality, with no real specific medicine for AKI. The carbonization product from Pollen Typhae (i.e., Pu-huang in China) has been extensively employed in clinic, and it is capable of relieving the renal damage and other diseases in China since acient times. RESULTS: Inspired by the carbonization process of Traditional Chinese Medicine (TCM), a novel species of carbon dots derived from Pollen Typhae (PT-CDs) was separated and then collected using a one-pot pyrolysis method. The as-prepared PT-CDs (4.85 ± 2.06 nm) with negative charge and abundant oxygenated groups exhibited high solubility, and they were stable in water. Moreover, the rhabdomyolysis (RM)-induced AKI rat model was used, and it was first demonstrated that PT-CDs had significant activity in improving the level of BUN and CRE, urine volume and kidney index, and histopathological morphology in RM-induced AKI rats. It is noteworthy that interventions of PT-CDs significantly reduced degree of inflammatory reaction and oxidative stress, which may be correlated with the basial potential mechanism of anti-AKI activities. Furthermore, cytotoxicity assay and biosafety evaluation exhibited high biocompatibility of PT-CDs. CONCLUSION: This study offers a novel relieving strategy for AKI based on PT-CDs and suggests its potential to be a related candidate for clinical applications.

Three birds, one stone: Disinfecting and turning waste medical masks into valuable carbon dots for sodium hydrosulfite and Fe3+ detection enabled by a simple hydrothermal treatment.

Disposable medical masks are widely used to prevent respiratory infections due to their ability to block virus particles from entering the human body. The coronavirus disease 2019 (COVID-19) pandemic highlighted the importance of medical masks, leading to their widespread use around the world. However, a large number of disposable medical masks have been discarded, some carrying viruses, which have posed a grave threat to the environment and people's health, as well as wasting resources. In this study, a simple hydrothermal method was used for the disinfection of waste medical masks under high-temperature conditions as well as for their transformation into high-value-added carbon dots (CDs, a new type of carbon nanomaterial) with blue-emissive fluorescence, without high energy consumption or environmental pollution. Moreover, the mask-derived CDs (m-CDs) could not only be used as fluorescent probes for sensing sodium hydrosulfite (Na2S2O4), which is widely used in the food and textile industries but is seriously harmful to human health, but also be used for detecting Fe3+ which is harmful to the environment and human health due to its wide use in industries.

Development of fluorescent lateral flow immunoassay for SARS-CoV-2-specific IgM and IgG based on aggregation-induced emission carbon dots.

Understanding the dynamic changes in antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is essential for evaluating the effectiveness of the vaccine and the stage for the recovery of the COVID-19 disease. A rapid and accurate method for the detection of SARS-CoV-2-specific antibodies is still urgently needed. Here, we developed a novel fluorescent lateral flow immunoassay (LFA) platform for the detection of SARS-CoV-2-specific IgM and IgG by the aggregation-induced emission carbon dots conjugated with the SARS-CoV-2 spike protein (SSP). The aggregation-induced emission carbon dots (AIE-CDs) are one of the best prospect fluorescent probe materials for exhibiting high emission efficiency in both aggregate and solid states. The AIE-CDs were synthesized and displayed dual fluorescence emission, which provides a new perspective for the design of a high sensitivity testing system. In this work, the novel LFA platform adopted the AIE carbon dots, which are used to detect SARS-CoV-2-specific IgM and IgG conveniently. Furthermore, this sensor had a low LOD of 100 pg/ml. Therefore, this newly developed strategy has potential applications in the areas of public health for the advancement of clinical research.

COVID-19 mitigation: nanotechnological intervention, perspective, and future scope

COVID-19 infections and severe acute respiratory syndrome (SARS) have caused an unprecedented health crisis across the globe with numerous deaths, as well as causing a tremendous economic crash worldwide. To combat this acute pathogenic coronavirus strain, a vital strategy of safe and effective diagnostic and therapeutic measures is highly important and demanding at present. Instead of conventional diagnosis tools, nanotechnology offers inspiring options for therapeutic applications that can ward off the disease from spreading further and remove the threat of this virus causing future pandemics. Physicochemically tuned nanomaterials can be exploited in upgrading detection schemes for viral antigens, nano-vaccines, and inhibitors of the cytokine storm, which are vital in the fight against COVID-19. The one-of-a-kind nanoscale biosynthesis of synthetic nanoparticles can efficiently imitate and interact with the structurally similar spike proteins present on the viral surface. Given this, we envision the precise and concurrent amalgamation of nanoscience and nanotechnology, leading to new avenues that can disrupt the development of viruses and limit the length of the viral lifespan. Current and developing nanotechnology approaches enable the development of therapeutic and precautionary pathways to curb this disease and identify crucial methods in the field of nanoscience for developing upcoming antiviral systems. In this review article, we also present a synopsis of the latest studies on the efficacy of nanoparticles (NPs) as antiviral or diagnostic devices against most viruses. Engineered NPs capable of tempering the patient's immune response can have a pronounced impact in mitigating inflammatory reactions as well as the design of potent nano-vaccines and drugs against viral pandemics such as COVID-19. In summary, state-of-the-art approaches based on nanotechnology can be critically deployed to counter future pandemics including COVID-19 and function at the forefront in tackling various new dangerous viral threats.

Recent advances of carbon dots as new antimicrobial agents

Due to the COVID‐19 pandemic, many rapid antimicrobial agents have developed intensively. Carbon dots (CDs), a new type of carbon‐based nanomaterials, shows great potential against emerging infectious diseases and antimicrobial‐resistant infections due to their unique optical properties, excellent biocompatibility, and easy surface modification. With the definition of the CDs structure and properties, synthesis, and characteristic technology improvement, the research on the CDs as antimicrobial agents has made significant progress. However, the lack of high repeatable and exact preparation methods, and the regular antimicrobial activity make it far from practical application. In this review, we summarize the most recent progress and challenges of CDs antimicrobial. First, an overview of the characteristics and properties is given, and the advantage of CDs applied to antimicrobial is further discussed. Then, it focuses on research progress on antimicrobial mechanisms under different conditions, the critical factors affecting their antimicrobial activity, and the practical antimicrobial applications. Finally, the main challenges and future research perspectives of antimicrobial CDs are proposed.

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.

Fluorescent-based nanosensors for selective detection of a wide range of biological macromolecules: A comprehensive review.

Thanks to their unique attributes, such as good sensitivity, selectivity, high surface-to-volume ratio, and versatile optical and electronic properties, fluorescent-based bioprobes have been used to create highly sensitive nanobiosensors to detect various biological and chemical agents. These sensors are superior to other analytical instrumentation techniques like gas chromatography, high-performance liquid chromatography, and capillary electrophoresis for being biodegradable, eco-friendly, and more economical, operational, and cost-effective. Moreover, several reports have also highlighted their application in the early detection of biomarkers associated with drug-induced organ damage such as liver, kidney, or lungs. In the present work, we comprehensively overviewed the electrochemical sensors that employ nanomaterials (nanoparticles/colloids or quantum dots, carbon dots, or nanoscaled metal-organic frameworks, etc.) to detect a variety of biological macromolecules based on fluorescent emission spectra. In addition, the most important mechanisms and methods to sense amino acids, protein, peptides, enzymes, carbohydrates, neurotransmitters, nucleic acids, vitamins, ions, metals, and electrolytes, blood gases, drugs (i.e., anti-inflammatory agents and antibiotics), toxins, alkaloids, antioxidants, cancer biomarkers, urinary metabolites (i.e., urea, uric acid, and creatinine), and pathogenic microorganisms were outlined and compared in terms of their selectivity and sensitivity. Altogether, the small dimensions and capability of these nanosensors for sensitive, label-free, real-time sensing of chemical, biological, and pharmaceutical agents could be used in array-based screening and in-vitro or in-vivo diagnostics. Although fluorescent nanoprobes are widely applied in determining biological macromolecules, unfortunately, they present many challenges and limitations. Efforts must be made to minimize such limitations in utilizing such nanobiosensors with an emphasis on their commercial developments. We believe that the current review can foster the wider incorporation of nanomedicine and will be of particular interest to researchers working on fluorescence technology, material chemistry, coordination polymers, and related research areas.

Exploration of nitrogen-doped grape peels carbon dots for baicalin detection

Baicalin, a flavonoid compound extracted from the rhizome of Scutellar iae Baicalensis, plays a vital role in improving liver function after injury, reducing liver disease and treating primary liver cancer, which is also the first SARS-CoV-2 3CLpro virus inhibitor according to the latest research data published in Bio-Rxiv. Therefore, constructing a simple and highly sensitive analytical method for the determination of baicalin is of great significance for the clinical and pharmacy settings. Herein, for the first time, carbon dots are explored for baicalin detection. Using biomass waste grape peels as the organic carbon source, nitrogen-doped fluorescent carbon dots (PT-NCDs) were fabricated, which were synthesized perfectly by a simple, environmentally friendly and one-step solid-phase thermal method without adding any other organic or acid/base reagents. Based on the synergistic effect of photo-induced electron transfer and dynamic quenching, a quenched fluorescence sensor for the determination of baicalin with a good linear range of 0.1-20 mu M and a satisfactory detection limit of 43.8 nM was constructed, which successfully quantified trace amount of baicalin in baicalin capsules, human serum and urine samples. The results indicate that PT-CDs are expected to become potential sensing materials for the real-time monitoring of baicalin in organisms, which is very important for our health. (C) 2021 Elsevier Ltd. All rights reserved.

Carbon dots for virus detection and therapy.

Recent experience with the COVID-19 pandemic should be a lesson learnt with respect to the effort we have to invest in the development of new strategies for the treatment of viral diseases, along with their cheap, easy, sensitive, and selective detection. Since we live in a globalized world where just hours can play a crucial role in the spread of a virus, its detection must be as quick as possible. Thanks to their chemical stability, photostability, and superior biocompatibility, carbon dots are a kind of nanomaterial showing great potential in both the detection of various virus strains and a broad-spectrum antiviral therapy. The biosensing and antiviral properties of carbon dots can be tuned by the selection of synthesis precursors as well as by easy post-synthetic functionalization. In this review, we will first summarize current options of virus detection utilizing carbon dots by either electrochemical or optical biosensing approaches. Secondly, we will cover and share the up-to-date knowledge of carbon dots' antiviral properties, which showed promising activity against various types of viruses including SARS-CoV-2. The mechanisms of their antiviral actions will be further adressed as well. Finally, we will discuss the advantages and distadvantages of the use of carbon dots in the tangled battle against viral infections in order to provide valuable informations for further research and development of new virus biosensors and antiviral therapeutics.

Nanobiotechnology in combating CoVid-19.

Emergence of novel pandemic viral disease CoVid-19 and its mutational behaviour are alarming. The potential use of nano-biotechnology in combating CoVid-19 is promising. We glean available data to explore such possibility in this short note.

Allium sativum derived carbon dots as a potential theranostic agent to combat the COVID-19 crisis.

Coronavirus disease 2019 (COVID-19) is one of the worst pandemics to have hit the humanity. The manifestations are quite varied, ranging from severe lung infections to being asymptomatic. Hence, there is an urgent need to champion new tools to accelerate the end of this pandemic. Compromised immunity is a primary feature of COVID-19. Allium sativum (AS) is an effective dietary supplement known for its immune-modulatory, antibacterial, anti-inflammatory, anticancer, antifungal, and anti-viral properties. In this paper, it is hypothesized that carbon dots (CDs) derived from AS (AS-CDs) may possess the potential to downregulate the expression of pro-inflammatory cytokines and revert the immunological aberrations to normal in case of COVID-19. CDs have already been explored in the world of nanobiomedicine as a promising theranostic candidates for bioimaging and drug/gene delivery. The antifibrotic and antioxidant effects of AS are elaborated, as demonstrated in several studies. It is found that the most active constituent of AS, allicin has a highly potent antioxidant and reactive oxygen species (ROS) scavenging effect. The antibacterial, antifungal, and anti-viral effects along with their capability of negating inflammatory effects and cytokine storm are discussed. The synthesis of theranostic CDs from AS may provide a novel weapon in the therapeutic armamentarium for the management of COVID-19 infection and, at the same time, could act as a diagnostic agent for COVID-19.

Developments in Nano-materials and Analysing its role in Fighting COVID-19.

Nanomaterials like silver, iron, ceramic, graphene carbon nanotubes, etc. These are used to develop and create multifunctional materials to fight the corona virus. This work focuses on analyzing and discussing the developments of Nano-materials and their effectiveness in fighting and preventing the spread of the corona virus. The paper also analyses the use of Nano-materials in the development of vaccines and anti-viral drugs. However, the use of carbon-based materials like carbon dots and other forms of carbon has not only helped in increasing the protection levels in human life but also provided greater security and freedom for people to carry out day-to-day activities without any fear of being infected by the virus. The application of graphene-based materials for making unique face masks and germ trap technologies is presented. Nano-compounds blended with hand sanitizers have played an active role in the control of coronavirus along with soap-based liquids that are used for handwashing. Some of the Nano-materials like gold nanoparticles are extensively used in the making of detection devices like RT-PCR, etc. The use of Nano-polymer coatings has created a safe environment for users by preventing the spread of coronavirus through surfaces. Different coating methods used for the application of nanomaterials are explained with suitable technical interpretations The anti-viral efficiency of different coatings is also discussed through surfaces. Nano-materials and contributions from the synthetic biology area have helped to develop vaccines and anti-viral drugs which are presently used to cure and prevent the spread of coronavirus infected patients. The method followed in analyzing the Nano-materials and their applications mainly focused on tracing the development and applications of Nano-materials. This analysis proves and shows that Nano-materials are playing a vital role in fighting the corona virus.

Functionality of nanomaterials and its technological aspects - Used in preventing, diagnosing and treating COVID-19.

COVID-19 (Coronavirus) has severely affected the life of human beings since December 2019. Many difficulties are faced by human beings to prevent the spread of the corona virus. However, this unexpected evolution of COVID-19 has also thrown many challenges to scientists and researchers so as to develop technologies that can be used to combat COVID-19. In the effort to combat COVID-19, many research universities and academic laboratories are also contributing by developing many technologies like Facing masks, hand sanitizers, hand washing machines, etc., to control and prevent the spread of COVID-19 disease. The use of Nano-materials is proving to be very effective in prevention, detection and diagnosis of COVID-19. In this paper many such technologies that are used to combat COVID-19 are also discussed. Some of the technologies like the germ trap technology used in face masks and hoods are also discussed. The use of nano-coatings, nano materials like graphene and carbon nano materials is playing a key role in preventing the spread of the virus. Antimicrobial nano-materials like silver nanoparticles are also effectively contributing to preventing the spread of the virus. Nano bio-sensors and gold nanoparticles are used in RT-PCR (Reverse transcription polymerase chain reaction) testing devices which are used for detection of coronavirus. The use of many nano chemicals and compounds has helped in making vaccines and anti-viral drugs that are today showing a way to safeguard human beings against the attack of this deadly virus.

Carbon-Based Nanomaterials: Promising Antiviral Agents to Combat COVID-19 in the Microbial-Resistant Era.

Therapeutic options for the highly pathogenic human severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing the current pandemic coronavirus disease (COVID-19) are urgently needed. COVID-19 is associated with viral pneumonia and acute respiratory distress syndrome causing significant morbidity and mortality. The proposed treatments for COVID-19 have shown little or no effect in the clinic so far. Additionally, bacterial and fungal pathogens contribute to the SARS-CoV-2-mediated pneumonia disease complex. The antibiotic resistance in pneumonia treatment is increasing at an alarming rate. Therefore, carbon-based nanomaterials (CBNs), such as fullerene, carbon dots, graphene, and their derivatives constitute a promising alternative due to their wide-spectrum antimicrobial activity, biocompatibility, biodegradability, and capacity to induce tissue regeneration. Furthermore, the antimicrobial mode of action is mainly physical (e.g., membrane distortion), characterized by a low risk of antimicrobial resistance. In this Review, we evaluated the literature on the antiviral activity and broad-spectrum antimicrobial properties of CBNs. CBNs had antiviral activity against 13 enveloped positive-sense single-stranded RNA viruses, including SARS-CoV-2. CBNs with low or no toxicity to humans are promising therapeutics against the COVID-19 pneumonia complex with other viruses, bacteria, and fungi, including those that are multidrug-resistant.

Carbon dot-polymer nanoporous membrane for recyclable sunlight-sterilized facemasks.

Facemasks are considered the most effective means for preventing infection and spread of viral particles. In particular, the coronavirus (COVID-19) pandemic underscores the urgent need for developing recyclable facemasks due to the considerable environmental damage and health risks imposed by disposable masks and respirators. We demonstrate synthesis of nanoporous membranes comprising carbon dots (C-dots) and poly(vinylidene fluoride) (PVDF), and demonstrate their potential use for recyclable, self-sterilized facemasks. Notably, the composite C-dot-PVDF films exhibit hydrophobic surface which prevents moisture accumulation and a compact nanopore network which allows both breathability as well as effective filtration of particles above 100 nm in diameter. Particularly important, self-sterilization occurs upon short solar irradiation of the membrane, as the embedded C-dots efficiently absorb visible light, concurrently giving rise to elevated temperatures through heat dissipation.

Exploring the Potential of Carbon Dots to Combat COVID-19.

Viral diseases are considered as a global burden. The eradication of viral diseases is always a challenging task in medical research due to the high infectivity and mutation capability of the virus. The ongoing COVID-19 pandemic is still not under control even after several months of the first reported case and global spread. Neither a specific drug nor a vaccine is available for public use yet. In the pursuit of a promising strategy, carbon dots could be considered as potential nanostructure against this viral pandemic. This review explores the possibility of carbon nano-dots to combat COVID-19 based on some reported studies. Carbon dots are photoluminescent carbon nanoparticles, smaller than 10 nm in dimension with a very attractive photostable and biocompatible properties which can be surfaced modified or functionalized. These photoluminescent tiny particles have captured much attention owing to their functionalization property and biocompatibility. In response to this pandemic outbreak, this review attempts to summarize the potential use of carbon dots in antiviral therapy with particular emphasis on their probable role in the battlefront against COVID-19 including their possible biosensing applications.