Unlocking the potential of green-engineered carbon quantum dots for sustainable packaging biomedical applications and water purification

Carbon quantum dots (CQDs) with well-defined architectures offer highly fascinating properties such as excellent water-solubility, exceptional luminescence, large specific surface area, non-toxicity, biocompatibility and tuneable morphological, structural, and chemical features. This review comprehensively overviews recent breakthroughs and critical milestones in the green synthesis of CQDs from renewable sources and provides guidance for their sustainable development towards fulfilling the goals of green chemistry. It also discusses the interaction of CQDs with various biopolymers to improve the material performance and functionality. This paper also highlights the latest technological applications of CQDs in numerous fields, including sustainable packaging, biosensing, bioimaging, cancer therapy, drug delivery as well as water purification. Finally, it summarizes the main challenges and provides an outlook on the future directions of CQDs in packaging and biomedical fields. This review can act as a roadmap to guide researchers for tailoring the properties of CQDs for important composite and biomedical fields.

Nitrogen doped carbon quantum dots: a multifaceted carbon nanomaterial that interferes in an amyloid-forming trajectory

Carbon quantum dots (CQDs) are a versatile class of carbon-based nanomaterial frameworks that have previously been used as a diagnostic device, in sensing for environmental applications, in bioimaging, and for drug delivery systems. Their versatility stems from their ability to be chemically tailored via functionalization to optimize properties for specific applications. In this study, we have synthesized lactic acid-derived nitrogen doped carbon quantum dots (LAdN-CQDs) and examined their ability to intervene in the conversion of soluble, monomeric hen egg-white lysozyme (HEWL) into mature fibrils. Our data indicate that LAdN-CQDs inhibit HEWL fibril formation in a dose-dependent manner (achieving up to 50% inhibition at 2.5 mg mL-1). Furthermore, in a neuroblastoma-derived cell line, LAdN-CQDs were found not to disrupt mitochondrial membrane potential or trigger apoptosis at the same concentration range, suggesting that they are biocompatible. LAdN-CQDs effectively neutralized reactive oxygen species (ROS), with a 50% decrease in ROS levels at just 100 μg mL-1 when challenged with an established free radical generator and protected the cell line from rotenone-induced apoptosis. The ability of LadN-CQDs to inhibit the soluble-to-toxic transformation of HEWL, the tolerance of SHSY-5Y cells to LAdN-CQDs, and their ability to restitute cells from rotenone-induced apoptosis, combined with the biocompatibility findings, suggest that LAdN-CQDs are potentially neuroprotective. The findings indicate that LAdN-CQDs represent a versatile, carbon-based, sustainable nanoplatform that bridges nanotechnology and neuroprotection, promoting the development of green chemistry-based healthcare solutions.

Biowaste-Derived Carbon Dots-Based Molecularly Imprinted Fluorescent Nanosensor for Selective Detection of Rutin

In this work, Waste pine nut shells were used as organic carbon source of biomass to synthesize carbon quantum dots. A highly responsive and selective fluorescent nanosensor (Si-doped biomass-derived carbon dots with molecular imprinted polymers, Si-CDs@MIPs) was designed for determination of Rutin (RT) in Chinese herbal substances like Sophora japonica L.. Not only was the synthesis method simple, environmentally friendly but also can selectively capture and specifically recognize the target compound RT, which was accomplished by a single-step hydrothermal process. The RT content in the real sample is 21%, with a recovery rate ranging from 89.7 to 106.3%, demonstrating excellent reproducibility. The nanosensor can selectively detect RT at a detection limit of 12.5 nmol/L. Therefore, it is showed that Si-CDs@MIPs will be feasible as a sensor for the rapid measurement of RT.

Advances in Carbon Dot Based Enhancement of Photodynamic Therapy of Tumors

Photodynamic therapy has advantages of high selectivity, less invasiveness, and high lethality for cancer cells compared with traditional treatment methods. However, some problems have hindered the development of photodynamic therapy, such as limited penetration depth, lack of oxygen, and toxicity. Carbon dots are widely used in the imaging and treatment of tumors due to their excellent optical and physicochemical properties, so effective methods have been explored to address the issues in photodynamic therapy via carbon dots. This review aims to elucidate the role of carbon dots in photodynamic therapy of cancer. Moreover, we summarize and discuss some strategies to harness carbon dots to enhance photodynamic therapy. Finally, we summarize many cancer synergistic therapeutic modalities involving carbon dots such as chemodynamic therapy, photothermal therapy, and immunotherapy in combination with photodynamic therapy to achieve more effective and safer treatments.

Carbon Quantum Dots in Biomedical Applications: Advances, Challenges, and Future Prospects

Carbon quantum dots (CQDs) represent a rapidly emerging class of nanomaterials with significant potential in biomedical applications due to their tunable fluorescence, high biocompatibility, and versatile functionalization. This review focuses on the recent progress in utilizing CQDs for drug delivery, bioimaging, biosensing, and cancer therapy. With their unique optical properties, such as tunable fluorescence, high quantum yield, and photostability, CQDs enable precise bioimaging and sensitive biosensing. Their small size, biocompatibility, and ease of surface functionalization allow for the development of targeted drug delivery systems, enhancing therapeutic precision and minimizing side effects. In cancer therapy, CQDs have shown potential in photodynamic and photothermal treatments by generating reactive oxygen species under light exposure, selectively targeting cancer cells while sparing healthy tissues. Furthermore, CQDs’ ability to penetrate biological barriers including the blood–brain barrier opens new possibilities for delivering therapeutic agents to hard‐to‐reach areas, such as tumors or diseased tissues. However, challenges such as optimizing synthesis, ensuring long‐term stability, and addressing safety concerns in biological environments remain critical hurdles. This review discusses current efforts to overcome these barriers and improve CQD performance in clinical settings, including scalable production methods and enhanced biocompatibility. As research progresses, CQDs are expected to play an important role in improving healthcare by offering more targeted treatment options and contributing to advancements in personalized medicine.

Fluorescent nanoparticles from roast duck induce cell damage and physiological dysfunction in Caenorhabditis elegans

BACKGROUND

The safety of fluorescent nanoparticles (FNPs) that enter the human body through food consumption is uncertain. In this study, the biocompatibility of FNPs derived from roast duck was investigated using pheochromocytoma (PC12) cells and Caenorhabditis elegans.

RESULTS

Fluorescent nanoparticles, at concentrations of 1 and 4 mg mL-1, caused an increase in early apoptosis, altered the cell cycle, elevated reactive oxygen species levels, and decreased mitochondrial membrane potential in PC12 cells. Both acute and prolonged exposure to the FNPs enabled them to permeate C. elegans via its food source, accumulating predominantly in the intestine. At concentrations ranging between 0 and 15 mg mL-1, FNPs did not induce mortality in C. elegans but they did affect its growth, reproductive ability, and motor behavior.

CONCLUSION

This study advances the understanding of FNP safety significantly, facilitates risk assessment for foods containing FNPs, and provides valuable guidance to ensure food safety. © 2024 Society of Chemical Industry.

A new herbal extract carbon nanodot nanomedicine for anti-renal cell carcinoma through the PI3K/AKT signaling pathway

New Re carbon nanodots with narrow size distribution, good water solubility and high cell membrane permeability were prepared from a herbal extract. They exhibited high inhibitory effects on renal cancer A498 cells and renal cell carcinoma. They could stimulate the production of ROS, induce mitochondrial dysfunction, and accelerate the release of intracellular calcium ions in the A498 cells. Transcriptomic tests were performed on A498 cells after administration, and the results were analyzed by qPCR and immunofluorescence. The results suggested that the Re carbon nanodots could downregulate the abnormally activated PI3K/AKT signaling pathway and perform cell cycle arrest in the S phase along with the inhibition of cell proliferation. Finally, in conjunction with the abnormal mitochondrial function, the Re carbon nanodots could ultimately promote the apoptosis of the A498 cells. In vivo tumor-bearing mouse experiments further showed that the Re carbon nanodots had a strong inhibitory effect on xenograft kidney cancer tumors. The prepared Re carbon nanodots have good anti-renal cancer A498 cell and renal cell carcinoma bioactivity and are expected to be a potential drug for the treatment of kidney cancer with low toxicity and high safety.

Biomass-derived carbon dots with pharmacological activity for biomedicine: Recent advances and future perspectives

Carbon dots (CDs), a type of nanoparticle with excellent optical properties, good biocompatibility, and small size, are finding increasing application across the fields of biology and biomedicine. In recent years, biomass-derived CDs with pharmacological activity (BP-CDs) derived from herbal medicines (HMs), HMs extracts and other natural products with demonstrated pharmaceutical activity have attracted particular attention. Herein, we review recent advances in the development of BP-CDs, covering the selection of biomass precursors, different methods used for the synthesis of BP-CDs from natural sources, and the purification of BP-CDs. Additionally, we summarize the many remarkable properties of BP-CDs including optical properties, biocompatibility and pharmaceutical efficacy. Moreover, the antibacterial, antiviral, anticancer, biosensing, bioimaging, and other applications of BP-CDs are reviewed. Thereafter, we discuss the advantages and disadvantages of BP-CDs and Western drug-derived CDs, highlighting the excellent performance of BP-CDs. Finally, based on the current state of research on BP-CDs, we suggest several aspects of BP-CDs that urgently need to be addressed and identify directions that should be pursued in the future. This comprehensive review on BP-CDs is expected to guide the precise design, preparation, and future development of BP-CDs, thereby advancing the application of BP-CDs in biomedicine.

Safety Evaluation of Carbon Dots in UM-UC-5 and A549 Cells for Biomedical Applications

BACKGROUNG

The rising complexity and associated side effects of cancer treatments highlight the need for safer and more effective therapeutic agents. Carbon-based nanomaterials such as CDs have been gaining prominence for their unique characteristics, opening avenues for diverse applications such as fluorescence imaging, drug and gene transport, controlled drug delivery, medical diagnosis, and biosensing. Despite promising advancements in research, it remains imperative to scrutinize the properties and potential cytotoxicity of newly developed CDs, ensuring their viability for these applications.

METHODS

We synthesized four N-doped CDs through a hydrothermal method. Cell viability assays were conducted on A549 and UM-UC-5 cancer cells at a range of concentrations and incubation times, both individually and with the chemotherapeutic agent 5-fluorouracil (5-FU).

RESULTS

The obtained results suggest that the newly developed CDs exhibit suitability for applications such as bioimaging, as no significant impact on cell viability was observed for CDs alone.

Graphene acid quantum dots: A highly active multifunctional carbon nano material that intervene in the trajectory towards neurodegeneration

Carbon dots (CDs) are carbon nano materials (CNMs) that find use across several biological applications because of their water solubility, biocompatible nature, eco-friendliness, and ease of synthesis. Additionally, their physiochemical properties can be chemically tuned for further optimization towards specific applications. Here, we investigate the efficacy of C70-derived Graphene Acid Quantum Dots (GAQDs) in mitigating the transformation of soluble, monomeric Hen Egg-White Lysozyme (HEWL) to mature fibrils during its amyloidogenic trajectory. Our findings reveal that GAQDs exhibit dose-dependent inhibition of HEWL fibril formation (up to 70 % at 5 mg/mL) without affecting mitochondrial membrane potential or inducing apoptosis at the same density. Furthermore, GAQDs scavenged reactive oxygen species (ROS); achieving a 50 % reduction in ROS levels at a mere 100 µg/mL when exposed to a standard free radical generator. GAQDs were not only found to be biocompatible with a human neuroblastoma-derived SHSY-5Y cell line but also rescued the cells from rotenone-induced apoptosis. The GAQD-tolerance of SHSY-5Y cells coupled with their ability to restitute cells from rotenone-dependent apoptosis, when taken in conjunction with the biocompatibility data, indicate that GAQDs possess neuroprotective potential. The data position this class of CNMs as promising candidates for resolving aberrant cellular outputs that associate with the advent and progress of multifactorial neurodegenerative disorders including Parkinson's (PD) and Alzheimer's diseases (AD) wherein environmental causes are implicated (95 % etiology). The data suggest that GAQDs are a multifunctional carbon-based sustainable nano-platform at the intersection of nanotechnology and neuroprotection for advancing green chemistry-derived, sustainable healthcare solutions.

Luminous blue carbon quantum dots employing Anisomeles indica (catmint) induce apoptotic signaling pathway in triple negative breast cancer (TNBC) cells

Herein, luminous blue carbon quantum dots (CDs) employing Anisomeles indica (Catmint) were reported with imaging, self-targeting, and therapeutic effects on triple-negative breast cancer (TNBC, MDA-MB-231) cells. The salient features of CDs generated from catmint are as follows: i) optical studies confirm CDs with excitation-dependent emission; ii) high-throughput characterization authenticates the formation of CDs with near-spherical shape with diameter ranging between 5 and 15 nm; iii) CDs induce cytotoxicity (3.22 ± 0.64 μg/ml) in triple-negative breast cancer (TNBC, MDA-MB-231) cells; iv) fluorescence microscopy demonstrates that CDs promote apoptosis by increasing reactive oxygen species (ROS) and decreasing mitochondrial membrane potential; v) CDs significantly up-regulate pro-apoptotic gene expression levels such as caspases-8/9/3. Finally, our work demonstrates that catmint-derived CDs are prospective nanotheranostics that augment cancer targeting and imaging.

Removal of Mo(VI), Pb(II), and Cu(II) from wastewater using electrospun cellulose acetate/chitosan biopolymer fibers

Environmentally friendly polymers such as cellulose acetate (CA) and chitosan (CS) were used to obtain electrospun fibers for Cu2+, Pb2+, and Mo6+ capture. The solvents dichloromethane (DCM) and dimethylformamide (DMF) allowed the development of a surface area of 148 m2 g-1 for CA fibers and 113 m2 g-1 for cellulose acetate/chitosan (CA/CS) fibers. The fibers were characterized by IR-DRIFT, SEM, TEM, CO2 sorption isotherms at 273 K, Hg porosimetry, TGA, stress-strain tests, and XPS. The CA/CS fibers had a higher adsorption capacity than CA fibers without affecting their physicochemical properties. The capture capacity reached 102 mg g-1 for Cu2+, 49.3 mg g-1 for Pb2+, and 13.1 mg g-1 for Mo6+. Furthermore, optimal pH, adsorption times qt, and C0 were studied for the evaluation of kinetic models and adsorption isotherms. Finally, a proposal for adsorbate-adsorbent interactions is presented as a possible capture mechanism where, in the case of Mo6+, a computational study is presented. The results demonstrate the potential to evaluate the fibers in tailings wastewater from copper mining.

Fluorescent Nanocarbons: From Synthesis and Structure to Cancer Imaging and Therapy

Nanocarbons are emerging at the forefront of nanoscience, with diverse carbon nanoforms emerging over the past two decades. Early cancer diagnosis and therapy, driven by advanced chemistry techniques, play a pivotal role in mitigating mortality rates associated with cancer. Nanocarbons, with an attractive combination of well-defined architectures, biocompatibility, and nanoscale dimension, offer an incredibly versatile platform for cancer imaging and therapy. This paper aims to review the underlying principles regarding the controllable synthesis, fluorescence origins, cellular toxicity, and surface functionalization routes of several classes of nanocarbons: carbon nanodots, nanodiamonds, carbon nanoonions, and carbon nanohorns. This review also highlights recent breakthroughs regarding the green synthesis of different nanocarbons from renewable sources. It also presents a comprehensive and unified overview of the latest cancer-related applications of nanocarbons and how they can be designed to interface with biological systems and work as cancer diagnostics and therapeutic tools. The commercial status for large-scale manufacturing of nanocarbons is also presented. Finally, it proposes future research opportunities aimed at engendering modifiable and high-performance nanocarbons for emerging applications across medical industries. This work is envisioned as a cornerstone to guide interdisciplinary teams in crafting fluorescent nanocarbons with tailored attributes that can revolutionize cancer diagnostics and therapy.

Microwave-assisted synthesis, characterization and in vitro biomedical applications of Hibiscus rosa-sinensis Linn.-mediated carbon quantum dots

In recent years, carbon quantum dots (CQDs) have garnered considerable attention as a promising material for biomedical applications because of their unique optical and biological properties. In this study, CQDs were derived from the leaves of Hibiscus rosa-sinensis Linn. via microwave-assisted technique and characterized using different techniques such as ultraviolet-visible, Fourier transform infrared, fluorescence spectrometry, X-ray diffraction, dynamic light scattering, transmission electron microscopy and energy-dispersive X-ray spectroscopy. Subsequently, their potential for biomedical applications was investigated through in vitro assays assessing scratch healing, anti-inflammatory, antibacterial, and cytotoxicity properties. It was found that the CQDs were fluorescent, polycrystalline, quasi-spherical, ~ 12 nm in size with presence of -OH and -COOH groups on their negatively charged surfaces, and demonstrated good anti-inflammatory by inhibiting protein denaturation, cyclooxygenase-2 and regulating inflammatory cytokines. The CQDs also exhibited antimicrobial activity against Klebsiella pneumoniae and Bacillus cereus, good biocompatibility, along with excellent promotion of cell proliferation in vitro, indicating their potential as a anti-inflammatory and wound healing material. The properties were more enhanced than their precursor, H. rosa-sinensis leaf extract. Hence, the CQDs synthesized from the leaves of H. rosa-sinensis can serve as a potential biomedical agent.

Carbon Quantum Dots: Properties, Preparation, and Applications

Carbon quantum dots are a novel form of carbon material. They offer numerous benefits including particle size adjustability, light resistance, ease of functionalization, low toxicity, excellent biocompatibility, and high-water solubility, as well as their easy accessibility of raw materials. Carbon quantum dots have been widely used in various fields. The preparation methods employed are predominantly top-down methods such as arc discharge, laser ablation, electrochemical and chemical oxidation, as well as bottom-up methods such as templates, microwave, and hydrothermal techniques. This article provides an overview of the properties, preparation methods, raw materials for preparation, and the heteroatom doping of carbon quantum dots, and it summarizes the applications in related fields, such as optoelectronics, bioimaging, drug delivery, cancer therapy, sensors, and environmental remediation. Finally, currently encountered issues of carbon quantum dots are presented. The latest research progress in synthesis and application, as well as the challenges outlined in this review, can help and encourage future research on carbon quantum dots.

Preparation of lignin-based full-color carbon quantum dots and their multifunctionalization with waterborne polyurethanes

Lignin is a popular material for energy transition and high-value utilization due to its low cost, non-toxicity, renewability, and widespread availability. However, its complex structure has hindered its application. Waterborne polyurethane (WPU) uses water as a dispersion medium, which is safer for humans and the environment but also leads to disadvantages such as poor mechanical properties and water resistance. In this study, we prepared multicolor photoluminescent carbon quantum dots (CQDs) in a wide range of wavelengths from lignin. We successfully prepared panchromatic CQDs by additive mixing. The redshift of the emission wavelength is attributed to the synergistic effect of the sp2 conjugated structure and the surface functional groups. The full-color solid-state luminescence of the CQDs was successfully achieved, and most importantly, the application of full-color CQDs in light-emitting diodes was realized. Moreover, the embedding of the multicolor CQDs in WPU not only makes WPU luminescent but also improves the water resistance and mechanical properties of WPUs. The hydrogen-bonding interactions between the functional groups on the surface of the CQDs and the urethane were responsible for the high performance of the composite. We investigated the UV and strong blue light shielding abilities of WPU/yellow CQDs films, which resulted from the unique absorption peaks of yellow CQDs in the UV region and the strong blue light region. This work provides an efficient method for the high-value utilization of biomass materials and paves the way for the multifunctional application of WPU.

Ultrasound-assisted and subcritical water extraction techniques for maximal recovery of phenolic compounds from raw ginger herbal dust toward in vitro biological activity investigation

This study examined the impact of two green extraction techniques in order to maximize the usage and recovery of phenolic compounds from the by-product of the filter tea industry, the so-called ginger herbal dust. The main phenolic compounds extraction was performed by ultrasound-assisted extraction (UAE) with the sonication amplitude ranging from 20% to 100%, and the subcritical water extraction (SWE), with the temperature ranging from 120 °C to 220 °C. All obtained extracts were characterized in terms of extraction yield, total phenolic content (TPC), and 6-ginerol, 6-shogaol, and 8-ginerol contents using RP-HPLC-DAD. Based on the results, we selected the extract obtained from raw ginger herbal dust using a sonication amplitude of 100% for further biological investigation of the cytotoxic effect on short- and long-term cell viability on liver and pancreatic cancer cells. This extract contained high TPC concentration, and 6-gingerol (44.57 mg/gDE), 8-gingerol (8.62 mg/gDE), and 6-shogaol (6.92 mg/gDE).

Tumor diagnosis using carbon-based quantum dots: Detection based on the hallmarks of cancer

Carbon-based quantum dots (CQDs) have been shown to have promising application value in tumor diagnosis. Their use, however, is severely hindered by the complicated nature of the nanostructures in the CQDs. Furthermore, it seems impossible to formulate the mechanisms involved using the inadequate theoretical frameworks that are currently available for CQDs. In this review, we re-consider the structure-property relationships of CQDs and summarize the current state of development of CQDs-based tumor diagnosis based on biological theories that are fully developed. The advantages and deficiencies of recent research on CQDs-based tumor diagnosis are thus explained in terms of the manifestation of nine essential changes in cell physiology. This review makes significant progress in addressing related problems encountered with other nanomaterials.

Carbon quantum dots derived from polysaccharides: Chemistry and potential applications

Since the beginning of 21th century, nanoscience and nanotechnology become the most promising topics in various fields, attributing to the superior characters of nanoscaled structures. The conventional quantum dots are substituted with new family of luminescent nanostructures, owing to their interchanged optical properties, low-cost of fabrication, biocompatibility, non-toxicity, ecofriendly, hydrophilicity and superior chemical stability. Carbon quantum dots (CQDs) were recently investigated for their simple synthesis, bio-consonance, and different revelation applicability. Obeying the green chemistry aspects, this review demonstrates an overview about CQDs generated from polysaccharides in brief, with a background on CQDs discovery, chemical composition, green synthesis via exploitation of different polysaccharides (cellulose, starch, pectin, chitin, etc) as biocompatible/biodegradable abundant biopolymers. Additionally, applications of CQDs originated from polysaccharides in environmental purposes, textiles industry and medical activities were also presented.

Room temperature cost-effective synthesis of carbon quantum dots for fluorescence pattern recognition of metal ions

Herein, a type of low-consuming carbon quantum dot (CD) has been synthesized at room temperature in just 45 minutes via Schiff base reaction between o-phthalaldehyde (OPA) and polyethyleneimine (PEI). These CDs are pH-dependent, so a novel label-free florescent sensor array can be constructed by utilizing buffers with various pH levels, which leads to distinctive fluorescence response patterns upon being challenged with metal ions for their pattern recognition. The results demonstrate that large-scale detection of metal ions can be achieved with as little as 3 types of sensors. Additionally, the sensors are able to discriminate between various metal ion concentrations and mixtures of different metal ions. The technique demonstrates potential uses in water quality monitoring by promising straightforward, quick, sensitive, and potent discrimination of metal ions.

An Overview of the Potential of Food-Based Carbon Dots for Biomedical Applications

Food-based carbon dots (CDs) hold significant importance across various fields, ranging from biomedical applications to environmental and food industries. These CDs offer unique advantages over traditional carbon nanomaterials, including affordability, biodegradability, ease of operation, and multiple bioactivities. This work aims to provide a comprehensive overview of recent developments in food-based CDs, focusing on their characteristics, properties, therapeutic applications in biomedicine, and safety assessment methods. The review highlights the potential of food-based CDs in biomedical applications, including antibacterial, antifungal, antivirus, anticancer, and anti-immune hyperactivity. Furthermore, current strategies employed for evaluating the safety of food-based CDs have also been reported. In conclusion, this review offers valuable insights into their potential across diverse sectors and underscores the significance of safety assessment measures to facilitate their continued advancement and application.

Potential Efficacy of Herbal Medicine-Derived Carbon Dots in the Treatment of Diseases: From Mechanism to Clinic

Carbon dots (CDs), a crucial component of nanomaterials, are zero-dimensional nanomaterials with carbon as the backbone structure and smaller than 10 nm. Due to their beneficial characteristics, they are widely used in biomedical fields such as biosensors, drug delivery, bio-imaging, and interactions with DNA. Interestingly, a novel type of carbon dot, generated by using herbal medicines as synthetic raw materials, has emerged as the most recent incomer in the family of CDs with the extensive growth in the number of materials selected for carbon dots synthesis. Herbal medicine-derived carbon dots (HM-CDs) have been employed in the biomedical industry, and are rapidly emerging as "modern nanomaterials" due to their unique structures and exceptional capabilities. Emerging trends suggest that their specific properties can be used in bleeding disorders, gastrointestinal disorders, inflammation-related diseases, and other common intractable diseases including cancer, menopausal syndrome, central nervous system disorders, and pain of various forms and causes. In addition, HM-CDs have been found to have organ-protective and antioxidant properties, as evidenced by extensive studies. This research provides a more comprehensive understanding of the biomedical applications of HM-CDs for the aforementioned disorders and investigates the intrinsic pharmacological activities and mechanisms of these HM-CDs to further advance their clinical applications.

Green synthesis of fluorescent carbon nanodots from sage leaves for selective anticancer activity on 2D liver cancer cells and 3D multicellular tumor spheroids

Carbon nanodots, a family of carbon-based nanomaterials, have been synthesized through different methods from various resources, affecting the properties of the resulting product and their application. Herein, carbon nanodots (CNDs) were synthesized with a green and simple hydrothermal method from sage leaves at 200 °C for 6 hours. The obtained CNDs are well dispersed in water with a negative surface charge (ζ-potential = -11 mV) and an average particle size of 3.6 nm. The synthesized CNDs showed concentration-dependent anticancer activity toward liver cancer (Hep3B) cell lines and decreased the viability of the cancer cells to 23% at the highest used concentration (250 μg ml-1 of CNDs). More interestingly, the cytotoxicity of the CNDs was tested in normal liver cell lines (LX2) revealed that the CNDs at all tested concentrations didn't affect their viability including at the highest concentration showing a viability of 86.7%. The cellular uptake mechanisms of CNDs were investigated and they are thought to be through energy-dependent endocytosis and also through passive diffusion. The main mechanisms of endocytosis were lipid and caveolae-mediated endocytosis. In addition, the CNDs have hindered the formation of 3D spheroids from the Hep3B hepatocellular carcinoma cell line. Hence, it would be concluded that the synthesized CNDs from sage are more highly selective to liver cancer cells than normal ones. The CNDs' cancer-killing ability would be referred to as the production of reactive oxygen species.

High energy density storage, antifungal activity and enhanced bioimaging by green self-doped heteroatom carbon dots

Self-heteroatom-doped N-carbon dots (N-CDs) with a 2.35 eV energy gap and a 65.5% fluorescence quantum yield were created using a one-step, efficient, inexpensive, and environmentally friendly microwave irradiation method. FE-SEM, EDX, FT-IR, XRD, UV-VIS spectroscopy, FL spectroscopy, and CV electrochemical analysis were used to characterise the produced heteroatom-doped N-CDs. The graphitic carbon dot surface is doped with heteroatom functional groups such (S, P, K, Mg, Zn) = 1%, in addition to the additional passivating agent (N), according to the EDX surface morphology and the spontaneous heteroatom doping was caused by the heterogeneous chemical composition of pumpkin seeds. These spontaneous heteroatom-doped N-CDs possess quasispherical amorphous graphitic structure with an average size of less than 10 nm and the interplaner distance of 0.334 nm. Calculations utilising cyclic voltammetry showed that the heteroatom-doped N-CDs placed on nickel electrodes had a high specific capacitance value of 1044 F/g at a scan rate of 10 mV/s in 3 M of KOH electrolyte solution. Furthermore, it demonstrated a high energy and power density of 28.50 Wh/kg and 3350 W/kg, respectively. The higher value of specific capacitance and energy density were attributed to the fact that the Ni/CDs electrode material possesses both EDLC and PC properties due to the sufficient surface area and the multiple active sites of the prepared N-CDs. Furthermore, the heteroatom N-CDs revealed the antifungal action and bioimaging of the "Cladosporium cladosporioides" mould, which is mostly accountable for economic losses in agricultural products. The functional groups of nitrogen, sulphur, phosphorus, and zinc on the surface of the CDs have strong antibacterial and antifungal properties as well as fluorescence enhanced bioimaging.

Carbon Dots Derived from Traditional Chinese Medicines with Bioactivities: A Rising Star in Clinical Treatment

In the field of carbon nanomaterials, carbon dots (CDs) have become a preferable choice in biomedical applications. Based on the concept of green chemistry, CDs derived from traditional Chinese medicines (TCMs) have attracted extensive attention, including TCM charcoal drugs, TCM extracts, and TCM small molecules. The design and preparation of CDs from TCMs (TCMs-CDs) can improve the inherent characteristics of TCMs, such as solubility, particle size distribution, and so on. Compared with other precursor materials, TCMs-CDs have outstanding intrinsic bioactivities and potential pharmacological effects. However, the research of TCMs-CDs in biomedicine is not comprehensive, and their mechanisms have not been understood deeply either. In this review, we will provide concise insights into the recent development of TCMs-CDs, with a major focus on their preparation, formation, precursors, and bioactivities. Then we will discuss the perfect transformation from TCMs to TCMs-CDs. Finally, we discuss the opportunities and challenges for the application of TCMs-CDs in clinical treatment.

Progress in drug delivery and diagnostic applications of carbon dots: a systematic review

Carbon dots (CDs), which have particle size of less than 10 nm, are carbon-based nanomaterials that are used in a wide range of applications in the area of novel drug delivery in cancer, ocular diseases, infectious diseases, and brain disorders. CDs are biocompatible, eco-friendly, easy to synthesize, and less toxic with excellent chemical inertness, which makes them very good nanocarrier system to deliver multi-functional drugs effectively. A huge number of researchers worldwide are working on CDs-based drug delivery systems to evaluate their versatility and efficacy in the field of pharmaceuticals. As a result, there is a tremendous increase in our understanding of the physicochemical properties, diagnostic and drug delivery aspects of CDs, which consequently has led us to design and develop CDs-based theranostic system for the treatment of multiple disorders. In this review, we aim to summarize the advances in application of CDs as nanocarrier including gene delivery, vaccine delivery and antiviral delivery, that has been carried out in the last 5 years.

Violuric acid carbon dots as a highly fluorescence probe for ultrasensitive determination of Zn (II) in tomato paste

Zinc is an essential metal since it plays an important role in biological systems, therefore, determination of zinc in food samples is important. Violuric acid was used to prepare highly fluorescent carbon dots (CDs), when it irradiated with ultraviolet radiation at 365 nm, a strong violet fluorescence was observed which caused by the increased amount of nitrogen in the CD structure, which were then successfully used for sensing zinc ion based on quenching of fluorescence. Violuric acid's hydrothermal carbonization reaction's temperature and time were simply optimized for better-quality performance of the CDs as-synthesized. The probe was characterized by HRTEM, SEM, XRD, EDX, fluorescence, UV-Visible absorption spectrophotometry, and FTIR. With a lower LOD 0.32 nM, the developed approach demonstrates an exceptional sensitivity and good selective response to the Zn²⁺ at 25℃. Compared to the results from ICP, the sensor was successfully used for determination of Zn²⁺ ions in tomato paste samples.

Recyclable waste Dry-cell batteries derived carbon dots (CDs) for detection of Two-fold metal ions and degradation of BTB dye

In modern era, electronic wastes are one of the major threats around us, most of them are reused with less efficiency instead of re-usage, and conversion into valuable products is highly recommended. In this work, we report an innovative approach for the synthesis of highly photoluminescent CDs from waste dry-cell batteries through one-step hydrothermal treatment for the detection and degradation of environmental pollutants. The as-prepared CDs were studied by X-ray photoelectron spectroscopy (XPS), HR-TEM studies, X-ray diffractometer (XRD), Raman spectrometer, FTIR spectroscopy, UV-visible spectrophotometer, and spectrofluorometric measurements. The calculated quantum yield for synthesized CDs was around 13 %. The CDs have uniform particle size distribution, strong photoluminescent behavior, and possess high stability against various environmental conditions. Also, CDs display the selective and sensitive detection of Cr⁶⁺ and Co²⁺ and ions with a detection limit of around 0.11 µM and 0.10 µM respectively. The possible mechanism of CDs was also examined. Moreover, the photocatalytic activity of CDs with Bromothymol Blue (BTB) dye was studied. The degradation efficiency of BTB dye can be achieved at around 84 % over 180 min under the irradiation of direct sunlight in presence of H₂O₂. To date, it's the first time we have recycled waste dry-cell batteries into CDs as an effective probe for the detection and decomposition of environmental pollution. Furthermore, this work provides not only an easier route to make good quality and improved photoluminescent CDs from waste material like used batteries and also paves way for the reconversion of global treating waste. Finally, the outstanding detection capability with multiple properties of as-prepared CDs provides various environmental applications like the detection of pollutants and carcinogenic polluted water treatment.

Nitrogen and copper-doped saffron-based carbon dots: Synthesis, characterization, and cytotoxic effects on human colorectal cancer cells

AIM

Doped carbon dots (CDs) have attracted tremendous attention in cancer therapy. We aimed to synthesize copper, nitrogen-doped carbon dots (Cu, N-CDs) from saffron and investigated their effects on HCT-116 and HT-29 colorectal cancer (CRC) cells.

MAIN METHODS

CDs were synthesized by hydrothermal method and characterized by transmission electron microscopy (TEM), energy-dispersive X-ray (EDX), Fourier transform infrared (FT-IR) spectroscopy, ultraviolet-visible (UV-Vis) absorption spectroscopy, and fluorescence spectroscopy. HCT-116 and HT-29 cells were incubated with saffron, N-CDs, and Cu, N-CDs for 24 and 48 h for cell viability. Cellular uptake and intracellular reactive oxygen species (ROS) were evaluated by immunofluorescence microscopy. Oil Red O staining was used to monitor lipid accumulation. Apoptosis was evaluated using acridine orange/propidium iodide (AO/PI) staining and quantitative real-time polymerase chain reaction (Q-PCR) assay. The expression of miRNA-182 and miRNA-21 was measured by Q-PCR, while the generation of nitric oxide (NO) and lysyl oxidase (LOX) activity was calculated by colorimetric methods.

KEY FINDINGS

CDs were successfully prepared and characterized. Cell viability decreased in the treated cells dose- and time-dependently. HCT-116 and HT-29 cells uptook Cu, N-CDs with a high level of ROS generation. The Oil Red O staining showed lipid accumulation. Concomitant with an up-regulation of apoptotic genes (p < 0.05), AO/PI staining showed increased apoptosis in the treated cells. In comparison to control cells, NO generation, and miRNA-182 and miRNA-21 expression significantly changed in the Cu, N-CDs treated cells (p < 0.05).

SIGNIFICANCE

The results indicated that Cu, N-CDs could inhibit CRC cells through the induction of ROS generation and apoptosis.

Lights and Dots toward Therapy-Carbon-Based Quantum Dots as New Agents for Photodynamic Therapy

The large number of deaths induced by carcinoma and infections indicates that the need for new, better, targeted therapy is higher than ever. Apart from classical treatments and medication, photodynamic therapy (PDT) is one of the possible approaches to cure these clinical conditions. This strategy offers several advantages, such as lower toxicity, selective treatment, faster recovery time, avoidance of systemic toxic effects, and others. Unfortunately, there is a small number of agents that are approved for usage in clinical PDT. Novel, efficient, biocompatible PDT agents are, thus, highly desired. One of the most promising candidates is represented by the broad family of carbon-based quantum dots, such as graphene quantum dots (GQDs), carbon quantum dots (CQDs), carbon nanodots (CNDs), and carbonized polymer dots (CPDs). In this review paper, these new smart nanomaterials are discussed as potential PDT agents, detailing their toxicity in the dark, and when they are exposed to light, as well as their effects on carcinoma and bacterial cells. The photoinduced effects of carbon-based quantum dots on bacteria and viruses are particularly interesting, since dots usually generate several highly toxic reactive oxygen species under blue light. These species are acting as bombs on pathogen cells, causing various devastating and toxic effects on those targets.

Bioaccumulation determines the toxicity of carbon dots to two marine dinoflagellates

With the ever-increasing application of carbon dots (CDs), a substantial amount will be released and assemble in the aquatic environment. Nevertheless, potential photodegradation of CDs in the aquatic environment, their accumulation and impacts in aquatic organisms remain unclear. Our study examined the toxicity of CDs to two marine dinoflagellates Prorocentrum micans and Prorocentrum donghaiense. Their bioaccumulation including the uptake and elimination kinetics was also determined. Significant photodegradation of CDs in seawater was observed. Moreover, both the degraded CDs and their photodegradation products were toxic to the dinoflagellates. Although P. donghaiense was more sensitive to CDs than P. micans with the median effect concentration 17.0 and 99.0 mg L^-1, respectively, such sensitivity difference disappeared when the toxicity data were plotted against cellularly accumulated CDs instead of their concentration in the experimental medium. Therefore, the higher sensitivity of P. donghaiense was attributable to its higher accumulation of CDs. Overall, the photodegradation and bioaccumulation of CDs should be considered when evaluating their environmental risks.

Fluorescent carbon dots tailored iron oxide nano hybrid system forin vivooptical imaging of liver fibrosis

Hybrid nanoparticles are innovative invention of last decade designed to overcome limitations of single-component nanoparticles by introducing multiple functionalities through combining two or more different nanoparticles. In this study, we are reporting development of magneto-fluorescent hybrid nanoparticles by combining iron oxide and carbon nanoparticles to enablein vivofluorescence imaging which also has all the required characteristic properties to use as Magnetic Resonance Imaging (MRI) contrast agent. In order to achieve dual-functional imaging, alginate and pullulan coated super paramagnetic iron oxide nanoparticles (ASPION and PSPION) and Carbon dots (Cdts) were synthesised separately. ASPIONs and PSPIONs were further chemically conjugated with Cdts and developed dual-functional nanohybrid particles ASPION-Cdts and PSPION-Cdts. Subsequently, evaluation of the materials for its size, functionalisation efficiency, fluorescence and magnetic properties, biocompatibility and cellular uptake efficiency has been carried out. Fluorescence imaging of liver fibrosis was performedin vivoin rodent model of liver fibrosis using the two nanohybrids, which is further confirmed by high fluorescence signal from the harvested liver.

Application of green-synthesized carbon dots for imaging of cancerous cell lines and detection of anthraquinone drugs using silica-coated CdTe quantum dots-based ratiometric fluorescence sensor

Chemotherapy drugs of daunorubicin and doxorubicin treat cancers with many side effects. So, detection of them in the biological system for regulation and controlling of usage is essential. In this study, a ratiometric fluorescent method was introduced for detection of daunorubicin and doxorubicin using bell pepper-based carbon dots, as the variable signal, and silica-coated CdTe quantum dots, as the constant signal. The detection was done based on variations of carbon dots intensity in the presence of drugs in comparison with the constant intensity of silica-coated CdTe quantum dots. The proposed ratiometric fluorescent method was successfully used for detection of daunorubicin and doxorubicin range of 54.37-13594.34 nmolL^-1 and 86.2-17242 nmolL^-1, with a detection limit of 18.53 nmolL^-1 and 29 nmolL^-1, respectively. Also, this method was used for detection of drugs in serum samples with recovery ranges of 86.14-99.62 (RSD 3-1.47%) and 86.32-97.53 (3.38-1.48%), respectively. Finally, after evaluation of carbon dots toxicity by MTT test, carbon dots was applied for imaging of prostate cancer cell lines (PC-3) and breast cancer cell lines (MCF7). The results demonstrated that despite improvement of the repeatability and interferences reduction by ratiometric method, also carbon dots were successfully applied for imaging of cell lines.

In vitro and in vivo toxicological evaluation of carbon quantum dots originating from Spinacia oleracea

Food-derived carbon quantum dots (CQDs) can relatively easily be synthesized and chemically manipulated for a broad spectrum of biomedical applications. However, their toxicity may hinder their actual use. Here, Spinacia oleracea-derived CQDs i.e., CQD-1 and CQD-2, were synthesized by means of different shredding methods and followed by a microwave-assisted hydrothermal approach. Subsequently, these CQDs were analyzed in vitro and in an in vivo mice model to test their biocompatibility and potential use as bioimaging agents and for activation of osteogenic differentiation. When comparing CQD-1 and CQD-2, it was found that CQD-1 exhibited 7.6 times higher photoluminescent (PL) emission intensity around 411 nm compared to CQD-2. Besides, it was found that the size distribution of CQD-1 was 2.05 ± 0.08 nm, compared with 2.14 ± 0.04 nm for CQD-2. Upon exposure to human bone marrow-derived mesenchymal stem cells (hBMSCs) in vitro, CQD-1 was endocytosed into the cytoplasm and significantly increased the differentiation of hBMSCs up to 10 μg mL^-1 after 7 and 14 days. Apparently, the presence of relatively low doses of CQD-1 showed virtually no toxic or histological effects in the major organs in vivo. In contrast, high doses of CQD-1 (1 mg mL^-1) caused cell death in vitro ranging from 35% on day 1 to 80% on day 3 post-exposure, and activated the apoptotic machinery and increased lymphocyte aggregates in the liver tissue. In conclusion, S. oleracea-derived CQDs have the potential for biomedical applications in bioimaging and activation of stem cells osteogenic differentiation. Therefore, it is postulated that CQD-1 from S. oleracea remains potential prospective material at appropriate doses and specifications.

Targeting Apoptotic Pathway of Cancer Cells with Phytochemicals and Plant-Based Nanomaterials

Apoptosis is the elimination of functionally non-essential, neoplastic, and infected cells via the mitochondrial pathway or death receptor pathway. The process of apoptosis is highly regulated through membrane channels and apoptogenic proteins. Apoptosis maintains cellular balance within the human body through cell cycle progression. Loss of apoptosis control prolongs cancer cell survival and allows the accumulation of mutations that can promote angiogenesis, promote cell proliferation, disrupt differentiation, and increase invasiveness during tumor progression. The apoptotic pathway has been extensively studied as a potential drug target in cancer treatment. However, the off-target activities of drugs and negative implications have been a matter of concern over the years. Phytochemicals (PCs) have been studied for their efficacy in various cancer cell lines individually and synergistically. The development of nanoparticles (NPs) through green synthesis has added a new dimension to the advancement of plant-based nanomaterials for effective cancer treatment. This review provides a detailed insight into the fundamental molecular pathways of programmed cell death and highlights the role of PCs along with the existing drugs and plant-based NPs in treating cancer by targeting its programmed cell death (PCD) network.

Research progress on Walnut oil: Bioactive compounds, health benefits, extraction methods, and medicinal uses

Walnut oil is extracted from walnut kernels (Juglans regia Linne) or iron walnut kernels (Juhlans sigillata Dode). The percentage of oil in walnuts is 52%-70%. The main constituents in oil are fatty acids, phenols, sterols, squalene, melatonin, vitamins, and minerals. Many extraction methods such as supercritical carbon dioxide extraction, maceration, modified "bligh and dyer extraction," aqueous enzymatic extraction, ultrasonic extraction, soxhlet extraction, and cold-press extraction methods are reported in the literature. Walnut oil showed anti-inflammatory, antitumor, antioxidant, immunomodulatory, neuroprotective, cardioprotective, antidiabetic, and antihyperlipidemic activities. The reported data in the literature suggest that walnut oil has many health benefits. This review summarizes the extraction methods, bioactive constituents, health benefits, and pharmacological actions of walnut oil. PRACTICAL APPLICATIONS: Walnut oil is a natural vegetable oil of significant importance due to their nutritional, and intelligence-boosting benefits. Several factors, including the processing parameters and the phytochemical profile, affect walnut oil products' flavor and color. In addition, storage environment of walnut oil can also affect walnut oil quality. Apart from the predominant ingredient fatty acids, the chemical composition of walnut oil comprises phenols, sterols, squalene, melatonin, vitamins, and minerals. These bioactive compounds are of potential value owing to their health-promoting benefits, including antioxidant, antitumor, and cholesterol-lowering effects. Many chemical constituents were isolated from walnut oil; however, all the compounds are not explored for their possible medicinal value. Thus, clinical studies, exploration of the therapeutic potential and the molecular mechanisms of all the compounds, and development of convenient dosage forms either for therapeutic or functional food purposes are warranted.

The Effects of Carbon Dots from Hordei Fructus Germinatus Carbonisatus on Glycometabolism and α-Glycosidase Activity

Hordei Fructus Germinatus Carbonisatus (HFC), the carbonized malt known as Maiya-tan in China, has been used as an effective natural treatment to improve digestion for a long time. In this research, we separated and distinguished CDs (carbon dots) from HFC, which were prepared using traditional methods. The HFC CDs had a lattice spacing of 0.26 nm and an average size of 4.3 nm, according to morphology investigations, which revealed that they were nearly spherical. The significant elements in the HFC CDs were C, O, and N. These HFC CDs produced several emissive traps between π − π* states because they had functional groups including C–OH, –NH, C=O, and C–H on their surface, according to X-ray photoelectron spectroscopy investigation. Our results indicated that HFC CDs could effectively reduce postprandial blood glucose and inhibit α-glycosidase in vitro, which suggested that HFC CDs may affect aspects of carbohydrate metabolism. This work indicates that HFC CDs may have the potential to play a crucial clinical role in regulating blood sugar.

Carbon nanoparticles induce DNA repair and PARP inhibitor resistance associated with nanozyme activity in cancer cells

Background

Quantum nanodots especially carbon nanoparticles (CNPs) have been widely studied in biomedicine in imaging, and drug delivery, but anti-cancer mechanisms remain elusive.

Methods

Here, we investigated a type of cell death induced by food (beet, soybean) derived CNPs in cancer cells and tested whether CNPs induced DNA damage and resistant to anti-cancer agent PARP inhibitor (PARPi) could be overcome by quantum calculations, TEM, AFM, FT-IR, soft agar assay, and cytotoxicity assay.

Results

At high doses, CNPs derived from beet lead to a pop-like apoptosis (Carbopoptosis) in cancer cells. Quantum mechanical calculations confirmed CNPs binding with phosphate groups as well as DNA bases. At low doses, CNPs develop PARPi drug resistance through interactions between CNPs and PARPi. A synergistic drug effect was achieved with the combination of phosphatase inhibitor (PPi), PARPi, and CNPs. This is corroborated by the fact that sulfur modulated CNPs which exhibit super high phosphatase nanozyme activity abrogated the CNPs induced colony formation in anchorage-independent cancer cell growth.

Conclusion

Thus, our data suggest the CNPs intrinsic nanozyme activity of phosphatase may crosstalk with drug resistance, which can be reversed upon modulations.

Recent advancement of bioinspired nanomaterials and their applications: A review

With the advancement in the field of nanotechnology, different approaches for the synthesis of nanomaterials have been formulated, among which the bioinspired or biomimetic nanoplatforms have been utilized for different biomedical applications. In this context, bioinspired or biomimetic nanoparticles (NPs) have been synthesized in which the inspiration for synthesis is taken from nature or its components. Innovations in bioengineering tools and bio-conjugation chemistry have enabled scientists to develop novel types of such nanoplatforms. They have several advantages over normal synthesis protocols. In this review, we 1) summarized nanomaterial types and their advancements in bioinspired nanotechnology therapies; 2) discussed the major types, novel preparation methods, and synthesis progress of NPs in current biomedical fields; 3) gave a brief account of the need for synthesizing NPs via a bioinspired route rather than their common route; 4) highlighted the updated information on the biomimetic synthesis of different types of NPs; and 5) provided future perspectives in the synthesis of novel NPs for their potential applications in biomedical sciences.

Humic Acids Affect the Detection of Metal Ions by Cyanobacteria Carbon Quantum Dots Differently

A "top-down" synthesis of carbon quantum dots (CQDs), novel fluorescent C materials from waste biomass, is both cost-effective and environmentally friendly. N-rich cyanobacteria are promising precursors to produce CQDs with high fluorescence (FL) intensity for the detection of metal ions. Herein, we synthesized cyanobacteria-based CQDs using a hydrothermal process and evidenced their high FL intensity and stability. The cyanobacteria-based CQDs showed powerful sensitivity for the specific detection of Fe³⁺ and Cr⁶⁺, which could be ascribed to (i) static FL quenching as a result of the interaction between -OH, -NH₂, and -COOH groups with the metal ions, (ii) internal filtering effects between the CQDs and Fe³⁺ or Cr⁶⁺, and (iii) fluorescence resonance energy transfer between CQDs and Cr⁶⁺. Humic acids (HAs) coexisting led to an underestimation of Fe³⁺ but an overestimation of Cr⁶⁺ by the CQDs due to the different FL quenching mechanisms of the CQDs. HAs sorbed Fe³⁺ and wrapped the CQDs to form a barrier between them, inhibiting FL quenching of CQDs by Fe³⁺. As for Cr⁶⁺, HAs reduced Cr⁶⁺ and also led to FL quenching; the sorbed HAs on the CQDs acted as a carrier of electrons between Cr⁶⁺ and the CQDs, enhancing FL quenching of the CQDs. This study is the first work to evidence the interference of HAs in the detection of metal ions by CQDs derived from cyanobacteria, which would enlighten the application of CQDs in a natural aqueous environment.

Carbon dots nanozyme for anti-inflammatory therapy via scavenging intracellular reactive oxygen species

Developing an efficient antioxidant for anti-inflammatory therapy via scavenging reactive oxygen species (ROS) remains a great challenge owing to the insufficient activity and stability of traditional antioxidants. Herein, we explored and simply synthesized a biocompatible carbon dots (CDs) nanozyme with excellent scavenging activity of ROS for anti-inflammatory therapy. As expected, CDs nanozyme effectively eliminate many kinds of free radicals including •OH, O2 •- , and ABTS+•. Benefiting from multienzyme activities against ROS, CDs nanozyme can decrease the levels of pro-inflammatory cytokines, resulting in good anti-inflammatory effect. Taken together, this study not only sheds light on design of bioactive antioxidants but also broadens the biomedical application of CDs in the treatment of inflammation.

Organic quantum dots: An ultrasmall nanoplatform for cancer theranostics

Tumours are the second leading cause of death globally, generating alterations in biological interactions and, as a result, malfunctioning of crucial genetic traits. Technological advancements have made it possible to identify tumours at the cellular level, making transcriptional gene variations and other genetic variables more easily investigated. Standard chemotherapy is seen as a non-specific treatment that has the potential to destroy healthy cells while also causing systemic toxicity in individuals. As a result, developing new technologies has become a pressing necessity. QDs are semiconductor particles with diameters ranging from 2 to 10 nanometers. QDs have grabbed the interest of many researchers due to their unique characteristics, including compact size, large surface area, surface charges, and precise targeting. QD-based drug carriers are well known among the many nanocarriers. Using QDs as a delivery approach enhances solubility, lengthens retention time, and reduces the harmful effects of loaded medicines. Several varieties of quantum dots used in drug administration are discussed in this article, along with their chemical and physical characteristics and manufacturing methods. Furthermore, it discusses the role of QDs in biological, medicinal, and theranostic applications.

Gelatin-derived carbon quantum dots mitigate herbicide-induced neurotoxic effects in vitro and in vivo

The herbicide and viologen, N, N'-dimethyl-4,4'-bipyridinium dichloride (Paraquat) is known to be toxic to neuronal cells by a multifactorial process involving an elevation in the levels of reactive oxygen species (ROS), the triggering of amyloid-protein aggregation and their accumulation, collectively leading to neuronal dyshomeostasis. We demonstrate that green-chemistry-synthesized sustainable gelatin-derived carbon quantum dots (CQDs) mitigate paraquat-induced neurotoxic outcomes and resultant compromise in organismal mortality. Gelatin-derived CQDs were found to possess antioxidant properties and ameliorated ROS elevation in paraquat-insulted neuroblastoma-derived SHSY-5Y cells, protecting them from herbicide-induced cell death. These CQDs also increased lifespan in paraquat-compromised Caenorhabditis elegans and herbicide-mediated dopamine neuron ablation. Collectively, the data underscore the ability of this sustainably synthesized, environmentally friendly biocompatible nanomaterial to protect cell lines and organisms against neurotoxic outcomes. The study findings strategically position this relatively novel nanoscopic carbon quantum framework for further testing in vertebrate trials of neurotoxic insult.