Green Carbon Dots Research Articles

A promising green fluorimetric approach for analysis of edoxaban in real human plasma using green carbon dots decorated with terbium ions

A promising green fluorimetric approach for analysis of edoxaban in real human plasma using green carbon dots decorated with terbium ions

Green florescent carbon dots synthesized from various household green wastes for detection of parathion methyl pesticide

The purpose of the current study was to examine the use of green household wastes, such as lemon peel, bottle gourd peel (BG), culinary banana peel, and sugarcane bagasse, as a source for synthesizing carbon dots (C-dots) and to determine how the composition of the material affected the functional characteristics of the C-dots and its interaction behaviour for detection of pesticide. The synthesized C-dots showed green fluorescence with varying particle sizes and red shifting fluorescence with more than 100 nm Stokes shift, indicating time and excitation dependent luminescence behaviour. C-dots produced from bottle gourd (BG) peel had a positive impact on the functional characteristics with a maximum emission of 514 nm and excitation of 410 nm. The SAED and TEM pattern confirmed its amorphous structure. The hydronium ion diameter and the quantum yield were 0.99 nm and 3.1 % respectively. Contributing towards food safety, the synthesized C-dots from BG showed significant behaviour in the detection of parathion methyl (MP) like organophosphorus pesticide (OP) as it conjugated with iron and 1 ppm of parathion methyl, which exhibited “Turn-Off-On” fluorescence behaviour with noticeable changed in intensity and act as a promising qualitative tool for detection of parathion methyl in real sample. The intensity of FL and concentration of OP is directly proportional which is established by the investigated OP in vegetable, fruit and water samples. The significance of iron and MP-OP was also investigated in the presence of other metal ions and pesticides and showed that the C-dots synthesized probe solution was reliable and sensitive towards the detection of MP-OP in real samples.

Medicinal Plants Derived Green Carbon Dots: Synthesis, Characterization and Their Potential Applications in Cancer Therapy.

This review aims to explore the synthesis, characterization, and potential applications of carbon dots (CDs) derived from medicinal plants for cancer prevention, highlighting their role as a promising alternative in nanotechnological approaches. A comprehensive literature search was conducted to gather information on the synthesis methods, complex matrices, characterization techniques, and potential applications of CDs derived from medicinal plants in cancer therapy. Carbon dots (CDs) have emerged as a subject of significant interest due to their favorable chemical and biological properties. Various precursors, including graphite, carbon black, and organic molecules, are utilized in the synthesis of CDs through chemical or physical methods. Notably, CDs derived from medicinal plants offer environmentally friendly alternatives, leveraging complex matrices such as aqueous, alcoholic, and hydroalcoholic extracts. This review emphasizes the green synthesis approaches, characterization techniques, and diverse applications of CDs, including drug transport, bioimaging, biosensing, and anti-cancer therapies. Furthermore, it highlights the advantages and disadvantages of different synthesis methods, aiding researchers in selecting appropriate techniques for continuous production. Carbon dots (CDs) represent a transformative advancement in nanotheranostics, offering a versatile platform for precise cancer diagnosis and therapy. With inherent anticancer properties, CDs hold promise in photodynamic therapy (PDT) and photothermal therapy (PTT), enabling precise tumor targeting while minimizing systemic toxicity. To address the limitations of standalone PDT and PTT, researchers are exploring multimodal treatment approaches integrating CDs. By leveraging the unique properties of CDs derived from medicinal plants, a new era of precision cancer therapy may be realized, emphasizing enhanced therapeutic outcomes and reduced adverse effects.

Dual color carbon dots for simultaneous dynamic fluorescence tracking of mitochondria and lysosomes

The development of fluorescent probes to monitor mitochondria and lysosomes will be helpful not only to realize the status monitoring of the organelles, but also to gain insights into their functions in both healthy and diseased states. Carbon Dots (CDs), as a nanomaterial with excellent properties, have provided new tools and methods for research in organelle imaging in recent years. In this study, we synthesized green fluorescence-emitting carbon dots (G-CDs) with mitochondria-targeting ability and red fluorescence-emitting carbon dots (R-CDs) with lysosome-targeting ability by using the same precursors. G-CDs are brightly with a quantum yield of up to 51.8 % and R-CDs have a long-wavelength emission of 611 nm. Based on the unique properties of G-CDs and R-CDs, we observed the changes of mitochondria during apoptosis and mitochondrial autophagy in HeLa cells by using G-CDs. And the dynamics of lysosomes in the inhibition of cellular autophagy and cellular necrosis were observed by utilizing the R-CDs. Furthermore, we observed human intestinal organoids samples stained by G-CDs and R-CDs, extending the relevant applications of carbon dots imaging to the organoids field, which brings forth new possibilities for research and drug development of related diseases.

Engineering of Green Carbon Dots for Biomedical and Biotechnological Applications.

Carbon dots (CDs) are attracting increasing research attention due to their exceptional attributes, including their biocompatibility, water solubility, minimal toxicity, high photoluminescence, and easy functionalization. Green CDs, derived from natural sources such as fruits and vegetables, present advantages over conventionally produced CDs, such as cost-effectiveness, stability, simplicity, safety, and environmental friendliness. Various methods, including hydrothermal and microwave treatments, are used to synthesize green CDs, which demonstrate strong biocompatibility, stability, and luminescence. These properties give green CDs versatility in their biological applications, such as bioimaging, biosensing, and drug delivery. This review summarizes the prevalent synthesis methods and renewable sources regarding green CDs; examines their optical features; and explores their extensive biological applications, including in bioimaging, biosensing, drug/gene delivery, antimicrobial and antiviral effects, formatting of mathematical components, cancer diagnosis, and pharmaceutical formulations.

Multimodal applications of green carbon dots derived from Potentilla indica (mock strawberry): Antioxidant, antimicrobial, and quenching based quercetin sensor

This study utilized a simple hydrothermal technique to synthesize negatively charged carbon dots from Potentilla indica fruit (MSTCDs) with antioxidant and broad-spectrum antimicrobial properties, as well as a specific capacity to detect quercetin. The characterization of MSTCDs was performed using spectrophotometry (UV–vis, fluorescence, X-ray photoelectron, and Fourier-transform infrared), zeta potential, and transmission electron microscopy. The prepared MSTCDs had an average size of 8 ± 0.22 nm and zeta potential of −21 mV. The prepared MSTCDs showed negligible cytotoxicity and were found to be biocompatible with human microglial cells. MSTCDs used the static quenching and inner filter effect as their two sensing mechanisms to detect quercetin. The fluorescence intensity of the MSTCDs decreased as the dose of quercetin increased, showing a linear correlation within the dose range of 0.01–70 μM (R2 = 0.9980) and the lowest detection limit of 2 nM. The prepared MSTCDs were applied to detect quercetin in the orange and grape juice, yielding values of 3.27 and 7.04 μM, respectively. Further, the MSTCDs displayed antioxidant activity by scavenging 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl, and hydroxyl radicals, with an EC50 value of 9.3, 140.82, and 187.91 µg/mL, respectively. The antiradical activity of MSTCDs was slightly lower than the ascorbic acid except for ABTS radicals, where MSTCDs showed superior scavenging ability (EC50 = 9.3 µg/mL) compared to the control (EC50 = 33.7 µg/mL). MSTCDs exhibited dose-dependent antimicrobial activity against fungi, Gram-negative bacteria, and Gram-positive bacteria. Thus, the developed CDs showed potential as antioxidant, antimicrobial, and quenching-based quercetin sensor.

Titania Doped CDs as Effective CT‐DNA Binders: A Novel Fluorescent Probe via Green Synthesis

AbstractCarbon dots (CDs), which belong to the class of zero‐dimensional carbon‐based nanomaterials, have garnered significant interest owing to their wide array of applications spanning from the electronics industry to the healthcare sector. This work employs a facile, inexpensive approach to synthesize green luminescent carbon dots (J‐10) from a potential medicinal plant named Justicia Wynaadensis by the one‐step hydrothermal method. A nanocomposite (JT‐10) of the CDs is prepared by adding TiO2 nanoparticles derived from green synthesis of Lavandula leaves. The J‐10 and JT‐10 are further characterized by X‐ray Diffraction spectroscopy (XRD), Transmission Electron Microscopy (TEM), Raman analysis X‐ray Photoelectron Spectroscopy (XPS), and Fourier transform infrared techniques (FTIR), UV–vis spectroscopy, Photoluminescence (PL), and Fluorescence or PL lifetime analysis. The average size of synthesized CDs is 1.85 nm and exhibits an excitation‐dependent fluorescence nature at 320 nm. PL lifetime analysis of J‐10 and JT‐10 is calculated to be 5.80 and 2.84 ns respectively. Offering these unique optical properties and biocompatibility, the synthesised material is suitable for investigating their binding affinity and interaction mechanisms with DNA. The use of JT‐10 in DNA binding studies contributes to the development of sustainable and efficient nanomaterials for applications in biosensors, drug delivery, and gene therapy.

Sappanwood-derived green luminescent carbon dots for enhancing performance of dye-sensitized solar cell

Sappanwood-derived green luminescent carbon dots for enhancing performance of dye-sensitized solar cell

Preparation of multi-functional active packaging film of Galla chinensis waste CDs/pullulan

In this study, multifunctional green carbon dots (CDs) have been synthesized using Galla chinensis waste (GCW) via hydrothermal method for the first time. An active packaging film has been developed in this work by combining CDs and pullulan (PL), using the solution-casting method. The microscopic morphology revealed that the CDs that were prepared using GCW exhibited good compatibility with PL. In addition, it also led to improvement in the toughness of the PL film (14.01 % to 20.26 %), along with its water vapor permeability value [1.31 to 0.53 (g·mm)/(kPa·h·m2)]. The composite films consisting of CDs exhibited good UV blocking rates for the UVA (90.41 %–7.87 %), UVB (87.76 %–0.08 %), and UVC (83.39 %–0 %) spectral ranges. The composite films exhibited strong antioxidant activity, and the clearance of ABTS and DPPH were obtained to be 93.61 % and 86.30 %, respectively. In addition, the composite films showed good antibacterial activity for E. coli and S. aureus, with a high antibacterial rate of up to 99.99 %. Finally, the non-contact preservation of strawberries over a duration of 10 d at room temperature confirmed that the prepared composite film can help preserve the quality of strawberries, as well as extended their shelf-life.

Gastroduodenal injury and repair mechanisms.

Although the mucosal barrier serves as a primary interface between the environment and host, little is known about the repair of acute, superficial lesions or deeper, persistent lesions that if not healed, can be the site of increased permeability to luminal antigens, inflammation, and/or neoplasia development. Studies on acute superficial lesions have been sparse in the past year, with more focus given to novel mechanisms of mucosal protection, and the way in which mature epithelial cells or committed stem cells dedifferentiate, reprogram, proliferate, and then regenerate the gastroduodenal mucosa after injury. For this, adenoviral therapy showed organ specific targeting with mRNA and protein expression of effectors to protect against mucosal injury and ulceration. A large database of plant-based agents known to protect against injury and ulceration was published, along with studies using plant-based compounds delivered with alginates, polysaccharide/gel floating rafts, or incorporated into nanoparticles or green carbon dots to improve targeting and retention at the ulcerated lesion. With RNA technology developing rapidly, particularly single-cell RNA sequencing, important and novel data was forthcoming on mucosal regeneration. In particular, the role of interleukin-17 hub proteins in mucosal healing was highlighted. The presence and role of injury reserve cells was determined, as was the composition of ligand gradients for cell differentiation in both stomach and duodenum. The role of amphiregulin in parietal cell differentiation from lineage-restricted stem cells and the Yap1 gene signature in metaplasia vs. healing ulcers were of particular importance. Additionally, studies unveiled the important role of mesenchymal stromal cells in differentiation and repair mechanisms, in Muse cells as an exciting new therapy for mucosal repair after injury, and the role of sympathetic neurons in activating the immune system to regulate mucosal repair mechanisms. Recent studies highlight novel mechanisms that promote mucosal regeneration after injury of the gastroduodenal mucosa.

Revolutionizing the sensing properties of green carbon dots for monitoring carbon dioxide and carbon monoxide at room temperature

Revolutionizing the sensing properties of green carbon dots for monitoring carbon dioxide and carbon monoxide at room temperature

Synthesis of Green Carbon Dots from Nephelium Lappaceum L. Seeds

In this study, rambutan (Nephelium Lappaceum L.) seeds were used to fabricate green carbon dots (gCDs) by employing a hydrothermal process. The synthesized CDs were evaluated using Fourier transform infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS) for the structural properties as well as UV-Vis and fluorescence spectrophotometry for the optical properties. UV-Vis examination revealed that the produced gCDs showed emission-dependent photoluminescence excitation, with two absorption peaks at 265 nm and 330 nm. The presence of functional groups and chemical composition such as C=C, C=O, -COOH, and -OH on the surface of gCDs was confirmed by the results of FTIR and XPS spectra. Consequently, gCDs present several opportunities for exploration in a range of applications.

Application of green tea residue-derived carbon dots in the detection of Fe3+ ions and imaging of Caco-2 cells

In this study, we successfully synthesized green luminescent carbon dots by using green tea residue as the precursor of carbon source. Based on the internal filter effect (IFE), the fluorescence emission intensity of the probe decreased significantly with the increase of Fe3 + concentration. Based on this, a linear relationship between Fe3 + concentration and the fluorescence emission intensity of the probe was established to semi-quantitatively detect Fe3 +. The results showed that the linear range was 1–400 μM, and the detection limit was 3.58 μM. In addition, the probe was further applied to actual samples, and it was found that the recovery rate was between 97.75% and 104.59%, and the relative standard deviation was below 1.81%. These findings underscore the considerable potential of the carbon dots for practical Fe3+ detection applications. In a further application, the fluorescent carbon dots were diluted and directly employed to stain Caco-2 cells. Remarkably, even after 10 and 20-fold dilutions, the Caco-2 cells displayed vivid fluorescence at the green excitation wavelength. This outcome suggests a promising avenue for the application of fluorescent carbon dots in the field of biology.

Ce-UiO-66-F4-based composites decorated with green carbon dots for universal adsorption of organic pollutants containing hydrogen bond donors and its application exploration

Efficient and stable water purification is essential for the protection of water resources. Current adsorbents based on metal–organic frameworks face limitations of restricted active sites and single adsorption objects. In this study, we developed a cost-effective and environmentally friendly Tea-L-CDs@Ce-UiO-66-F4 composites by growing Tea and L-tryptophan carbon dots (Tea-L-CDs) over Ce-UiO-66-F4 MOF, and the interaction force was enhanced by hydrogen bonding (-F/O/N…H-O-, -F/O/N…H-N-, etc.) to achieve universal adsorption. In detail, the maximum adsorption capacity (qm) of the adsorbent for trypan blue (TB), congo red (CR), and CR (adjust pH) was 773.4, 1428.6, and 4761.9 mg/g. The universal experiment showed that the composites exhibited excellent qm for alizarin red S (ARS, 662.7 mg/g) and rhodamine B (RdB, 374.0 mg/g). Meanwhile, Tea-L-CDs@Ce-UiO-66-F4 composites maintained good anti-interference ability (salt solution, temperature, etc.). Remarkably, the adsorption capacity of the adsorbent for dyes exceeded 97 % of qm within 1 min of contact time. The adsorption performance of synthetic material for TB, CR, ARS, and RdB is better than most of the adsorbents, especially the qm for TB is higher than any adsorbent previously reported. Besides, this adsorbent had excellent storage stability in the air for 30 days. Based on this nanomaterial, we successfully developed an automated dye filtration and contamination assessment system for blocking dye-attached adsorbent and online detection of dye residues after water purification. Thus, the synthesized Tea-L-CDs@Ce-UiO-66-F4 composites, with universal adsorption, high efficiency, and good storage stability, hold great potential for wastewater purification.

Functionalized Green Carbon dots for Specific Detection of Copper in Human Serum Samples and Living Cells.

Intracellular copper ion (Cu2+) is irreplaceable and essential in regulation of physiological and biological processes, while excessive copper from bioaccumulation may cause potential hazards to human health. Hence, effective and sensitive recognition is urgently significant to prevent over-intake of copper. In this work, a novel highly sensitive and green carbon quantum dots (Green-CQDs) were synthesized by a low-cost and facile one-step microwave auxiliary method, which utilized gallic acid, carbamide and PEG400 as carbon source, nitrogen source and surface passivation agent, respectively. The decreased fluorescence illustrated excellent linear relationship with the increasing of Cu2+ concentration in a wide range. Substantial surface amino and hydroxyl group introduced by PEG400 significantly improved selectivity and sensitivity of Green-CQDs. The surface amino chelation mechanism and fluorescence internal filtration effect were demonstrated by the restored fluorescence after addition of EDTA. Crucially, the nanosensor illustrated good cell permeability, high biocompatibility and recovery rate, significantly practical application in fluorescent imaging and biosensing of intracellular Cu2+ in HepG-2 cells, which revealed a potential and promising biological applications in early diagnosis and treatment of copper ion related disease.

Efficient electrochemical synthesis of green fluorescent carbon dots for curcumin detection in common foods

Curcumin (Cur) is commonly employed as a food additive in the pharmaceutical and food industries. However, improper use of curcumin can lead to adverse effects on human health. In this research, we developed an electrochemical approach for the synthesis of green fluorescence nitrogen and sulfur co-doped carbon dots (G-CDs) specifically designed for curcumin detection. The prepared G-CDs displayed strong fluorescent emissions at 540 nm, along with notable attributes such as excellent fluorescence stability against photobleaching, and resilience to changes in ionic strength. The G-CDs demonstrated selective recognition of curcumin, resulting in fluorescence quenching in a linear range of 0–140 μmol/L, with an impressive detection limit of 46.4nmol/L. Five distinct food samples were effectively detected for curcumin using the developed G-CDs nanoprobe, yielding satisfactory outcomes. This newly proposed approach offers simplicity, outstanding sensitivity, and selectivity, showcasing its promising capabilities as an alternative method for Cur detection without the need for specialized instruments.

Chitosan modified magnetic nanocomposite for biofilm destruction and precise photothermal/photodynamic therapy

Getting rid of the biofilms is a major challenge when treating skin and soft tissue infections (SSTI), an inflammatory illness brought on by bacteria. Traditional magnetic materials have a limited dispersibility and a biofilm permeable property, making it challenging to remove biofilms and causing infection to linger. To solve these problems, we developed a kind of magnetic composite nanoplatform coated with indocyanine green carbon dots and modified with chitosan modification (Fe-ICGCDs@CS). Fe-ICGCDs@CS has high dispersibility and improves the conductivity of biofilms under magnetic action. Fe-ICGCDs@CS can adsorb bacteria via the positive charge and achieve precise photothermal sterilization and photodynamic therapy (PDT). Moreover, by catalyzing hydrogen peroxide (2 mM), Fe-ICGCDs@CS can produce oxygen to relieve the anoxic state in the deep layer of biofilms and activate dormant bacteria to make them sensitive to external stimuli. All in all, unlike the common “just kill” sterilization model, Fe-ICGCDs@CS can accurately kill bacteria and be recovered by an external magnetic field at the end of treatment, thus reducing the potential biological toxicity of nanomaterials. Therefore, the proposed Fe-ICGCDs@CS provides a new antibacterial method with low biotoxicity for clinical application in the treatment of biofilm infections.

Synthesis of Green Photoluminescence Carbon Dots Using Edible Seafood Mushroom and Their Anti‐Counterfeiting Applications

AbstractCarbon dots (CDs) have emerged as versatile fluorescent nanomaterials for diverse applications. The synthesis of CDs from natural products offers a sustainable alternative to chemical methods. This study presents the preparation of green fluorescent CDs (G‐CDs) using seafood mushrooms as the carbon source and 5‐amino‐2‐methylphenol as the nitrogen source through a hydrothermal approach. The G‐CDs exhibit maximum excitation/emission peaks at 467/519 nm and a high quantum yield of up to 17.2% in ethanol. Additionally, the G‐CDs demonstrate excellent photostability, salt tolerance, and chemical stability. The excitation‐independent emissions suggest the presence of unique surface‐state luminescent centers. The application of the G‐CDs as an anti‐counterfeiting fluorescent ink is demonstrated. This work highlights the promise of converting natural food sources into high‐performance CDs, expanding their utility across various domains including biomedicine, sensing, and security.

Novel Carbon Dots Derived from Moutan Cortex Significantly Improve the Solubility and Bioavailability of Mangiferin.

Mangiferin (MA), a bioactive C-glucosyl xanthone with a wide range of interesting therapeutic properties, has recently attracted considerable attention. However, its application in biomedicine is limited by poor solubility and bioavailability. Carbon dots (CDs), novel nanomaterials, have immense promise as carriers for improving the biopharmaceutical properties of active components because of their outstanding characteristics. In this study, a novel water-soluble carbon dot (MC-CDs) was prepared for the first time from an aqueous extract of Moutan Cortex Carbonisata, and characterized by various spectroscopies, zeta potential and high-resolution transmission electron microscopy (HRTEM). The toxicity effect was investigated using the CCK-8 assay in vitro. In addition, the potential of MC-CDs as carriers for improving the pharmacokinetic parameters was evaluated in vivo. The results indicated that MC-CDs with a uniform spherical particle size of 1-5 nm were successfully prepared, which significantly increased the solubility of MA in water. The MC-CDs exhibited low toxicity in HT-22 cells. Most importantly, the MC-CDs effectively affected the pharmacokinetic parameters of MA in normal rats. UPLC-MS analysis indicated that the area under the maximum blood concentration of MA from mangiferin-MC-CDs (MA-MC-CDs) was 1.6-fold higher than that from the MA suspension liquid (MA control) after oral administration at a dose of 20 mg/kg. Moutan Cortex-derived novel CDs exhibited superior performance in improving the solubility and bioavailability of MA. This study not only opens new possibilities for the future clinical application of MA but also provides evidence for the development of green biological carbon dots as a drug delivery system to improve the biopharmaceutical properties of insoluble drugs.

Study on structure and molecular scale protection mechanism of green Ce,N-CDs anti-bacterial and anti-corrosive inhibitor

Using l-histidine and cerium nitrate hexahydrate as raw materials, a green and effective carbon dots (Ce,N-CDs) was prepared using hydrothermal synthesis and their structures were confirmed by professional equipment. The anti-bacterial and anti-corrosive behaviors of Ce,N-CDs were systemically evaluated using plate counting method and electrochemical method, respectively. By analysis, the Ce,N-CDs showed a high bacterial inhibition efficiency for Escherichia coli (E. coli), which was up to 94.27 %. Compared with N-doping carbon dots (N-CDs), the Ce,N-CDs exhibited an excellent anti-corrosive ability. At 200 mg/l, its corrosion inhibition efficiency (IE) for Cu was higher than 90 % at different environment temperatures (308, 318, 323 K), and the corrosion rate (WL) was sharply reduced. This was attributed to the presence of N–Cu bond and the formation of Ce-containing passive film. The Ce-containing passive film could block the erosion of aggressive ions. The N–Cu bond could facilitated the chemical adsorption on Cu surface, which was confirmed by quantum chemistry (QC) and molecular dynamics (MD).