ABSTRACT
In this study, top-down syntheses of carbon dots (CDs) from four different carbon precursors, namely, carbon nano powders, graphite, graphene, and carbon nanotubes, were carried out. Systematic study demonstrated that the optical properties and surface functionalities of the CDs were quite similar and mainly influenced by the synthesis method, while the sizes, morphologies, chemical compositions, and core structures of the CDs were heavily influenced by the carbon precursors. On the basis of these studies, the formation processes and structural models of these four top-down CDs were proposed. The cell cytotoxicity and photothermal conversion efficiency of these CDs were also carefully evaluated, demonstrating their potential applications in photothermal therapy.
Subject(s)
Graphite/chemistry , Models, Structural , Nanotubes, Carbon/chemistry , Photothermal Therapy , Quantum Dots/chemistry , A549 Cells , Cell Death , HaCaT Cells , Humans , Nanotubes, Carbon/ultrastructure , Optical Phenomena , Oxidation-Reduction , Powders , Quantum Dots/ultrastructure , Spectrometry, Fluorescence , Spectrophotometry, Ultraviolet , Spectrum Analysis, Raman , Static Electricity , Surface Properties , Thermogravimetry , X-Ray DiffractionABSTRACT
The synthesis of lignin-based graphene quantum dots (GQDs) with excellent fluorescence stability, quantum yield, and biocompatibility for sensitive and selective detection of Fe3+ and ascorbic acid (AA) has remained a challenging endeavor. Using an acidolysis process with 17.5% nitric acid followed by hydrothermal treatment at 200 °C, this study provided an improved synthesis route for the production of high-quality GQDs from alkali lignin. The nitrogen-doped GQDs exhibit remarkable fluorescence stability under a wide range of pH (3-10), duration (1-12 h), and [NaCl] (0-1000 mM) conditions, and have a high quantum yield of 28%. The GQDs or GQDs/Fe3+ sensing systems ([GQDs] at 50 mg L-1, [Fe3+] at 500 µmol L-1, and UV excitation at 370 nm) for fluorescence sensing of Fe3+ or AA have excellent sensitivity, selectivity, and reproducibility. For Fe3+ and AA, the limit of detection is 1.49 and 1.62 µmol L-1, respectively. Mechanism investigation shows that photoluminescence quenching is caused by the formation of GQDs-Fe3+ complexes, whereas fluorescence recovery is due to Fe3+ reduction by AA.
Subject(s)
Ascorbic Acid/analysis , Biosensing Techniques , Ferric Compounds/analysis , Graphite/chemistry , Lignin/chemistry , Quantum Dots/chemistry , Cell Survival , Chemical Phenomena , Chemistry Techniques, Synthetic , Fluorescence , Graphite/chemical synthesis , Humans , Microscopy, Atomic Force , Quantum Dots/ultrastructureABSTRACT
In this work, binding interaction between molybdenum disulfide quantum dots (MoS2 QDs) and human serum albumin (HSA) was researched deeply to dissect the conformational variation and fibrillation of HSA affected by MoS2 QDs. The results revealed that MoS2 QDs bound strongly with HSA with molar ratio of 1:1 under the joint actions of hydrogen bond and van der Waals force, leading to the static fluorescence quenching of HSA. MoS2 QDs caused the secondary structure transition of HSA from α-helix stepwise to ß-turn, ß-sheet, and random coil gradually. MoS2 QDs reduced both the molar enthalpy change and the melting temperature of HSA, reducing the thermal stability of HSA significantly. It is worth noting that MoS2 QDs inhibited the fibrillation process of HSA according to the reduced hydrophobic environment and the disturbance of disulfide bonds in HSA network structure. These results reveal the precise binding mechanism of MoS2 QDs with HSA at molecular level, providing indispensable information for the potential application of MoS2 QDs in biological fields.
Subject(s)
Disulfides/chemistry , Molybdenum/chemistry , Quantum Dots/chemistry , Serum Albumin, Human/chemistry , Binding Sites , Electrochemistry , Humans , Models, Molecular , Protein Binding , Protein Conformation , Quantum Dots/ultrastructure , Spectrometry, Fluorescence , Spectroscopy, Fourier Transform Infrared , Static Electricity , ThermodynamicsABSTRACT
There is an urgent need for materials that can efficiently generate reactive oxygen species (ROS) and be used in photodynamic therapy (PDT) as two-photon imaging contrast probes. In this study, graphene quantum dots (GQDs) were subjected to amino group functionalization and nitrogen doping (amino-N-GQDs) via annealing and hydrothermal ammonia autoclave treatments. The synthesized dots could serve as a photosensitizer in PDT and generate more ROS than conventional GQDs under 60-s low-energy (fixed output power: 0.07 W·cm-2) excitation exerted by a 670-nm continuous-wave laser. The generated ROS were used to completely eliminate a multidrug-resistant strain of methicillin-resistant Staphylococcus aureus (MRSA), a Gram-positive bacterium. Compared with conventional GQDs, the amino-N-GQDs had superior optical properties, including stronger absorption, higher quantum yield (0.34), stronger luminescence, and high stability under exposure. The high photostability and intrinsic luminescence of amino-N-GQDs contribute to their suitability as contrast probes for use in biomedical imaging, in addition to their bacteria tracking and localization abilities. Herein, the dual-modality amino-N-GQDs in PDT easily eliminated multidrug-resistant bacteria, ultimately revealing their potential for use in future clinical applications.
Subject(s)
Anti-Bacterial Agents/administration & dosage , Contrast Media/chemistry , Drug Carriers/chemistry , Graphite/chemistry , Methicillin-Resistant Staphylococcus aureus/drug effects , Nitrogen/chemistry , Quantum Dots/chemistry , Antioxidants/administration & dosage , Microbial Sensitivity Tests , Quantum Dots/ultrastructureABSTRACT
We prepared the magnetic chitosan carbon quantum dot nanoparticles (Fe3O4@CQD NPs) via the hydrothermal treatment of chitosan biopolymer and then its magnetization with Fe3O4 nanoparticles. (4-Acetylphenyl)boronic acid compound was utilized for the modification of surface of Fe3O4@CQD nanoparticles via the covalent imine bond formation between NH2 groups of chitosan quantum dot with carbonyl functional of acetyl-substituted arylboronic acid. The synthesized Fe3O4@CQD@AP-B(OH)2 was characterized by FE-SEM, EDS, XRD, VSM and ICP-OES analysis and its fluorescence property was studied. This magnetic multifunctional nanoplatform sensor has shown high potential sensitivity for Cu2+ ions (in the range of 1.0-30.0 µM with limit of detection 0.3 µM) through interaction of cupric ions with the boronic-acid moiety.
Subject(s)
Boronic Acids/chemistry , Chitosan/chemistry , Copper/analysis , Magnetic Phenomena , Nanocomposites/chemistry , Quantum Dots/chemistry , Boronic Acids/chemical synthesis , Cations , Chitosan/chemical synthesis , Fluorescence , Ions , Nanocomposites/ultrastructure , Quantum Dots/ultrastructure , Spectroscopy, Fourier Transform Infrared , X-Ray DiffractionABSTRACT
Overexpression of collagenase, elastase, and tyrosinase is caused by external factors such as ultraviolet (UV) radiation and stress, resulting in wrinkle formation and freckles through the loss of skin elasticity and skin pigmentation. In this study, we developed novel carbon quantum dots (CQDs) with antioxidant and anti-aging properties using tannic acid as a carbon source through a simple microwave-assisted pyrolysis method. The synthesized tannic acid-derived CQDs (T-CQDs) showed bright blue fluorescence (QY = 28.2 ± 4.0%), exhibiting maximum emission at 430 nm under 350 nm excitation. Even though small amount of the T-CQDs (3µg ml-1) was used, they exhibited excellent free radical scavenging ability (82.8 ± 4.3%). Also, the T-CQDs (10µg ml-1) revealed remarkable inhibitory activity against skin aging-related collagenase (77.6 ± 4.8%), elastase (52.6 ± 1.0%), and tyrosinase (44.2 ± 1.3%), demonstrating their antioxidant and anti-aging effects. Furthermore, their antioxidant and anti-aging properties were superior to those of tannic acid, L-ascorbic acid, and quercetin used as positive controls. Finally, the T-CQDs effectively suppressed UV-induced reactive oxygen species generation by 30% at the cellular levels and showed high cell viability (99.7 ± 0.8%) even at 500µg ml-1. These results demonstrate that the T-CQDs with superior antioxidant, anti-aging properties, and low cytotoxicity can be utilized as novel anti-aging materials in cosmetic and nanomedicine fields.
Subject(s)
Antioxidants/pharmacology , Carbon/pharmacology , Collagenases/metabolism , Enzyme Inhibitors/pharmacology , Monophenol Monooxygenase/antagonists & inhibitors , Pancreatic Elastase/antagonists & inhibitors , Quantum Dots/chemistry , Antioxidants/chemical synthesis , Ascorbic Acid/pharmacology , Biphenyl Compounds/antagonists & inhibitors , Carbon/chemistry , Cell Line, Tumor , Cell Survival/drug effects , Enzyme Inhibitors/chemical synthesis , Ethylenediamines/chemistry , Geroscience/methods , Humans , Melanocytes/cytology , Melanocytes/drug effects , Melanocytes/enzymology , Microwaves , Monophenol Monooxygenase/metabolism , Pancreatic Elastase/metabolism , Picrates/antagonists & inhibitors , Quantum Dots/ultrastructure , Quercetin/pharmacology , Tannins/chemistry , Tannins/pharmacologyABSTRACT
PURPOSE: Sensitive and selective point-of-care biosensor is an urgent pursuit of serological antibody detection to control parasite pathogen. For specific, quantitative and on-site screening of Trichinella spiralis infection in livestock, a quantum dot nanobead-monoclonal antibody (QB-mAb) probe-based immunochromatographic assay (ICA) was developed by introducing a competitive sandwich strategy (QB-CICA). METHODS: In the QB-CICA, QB-mAb probes competed with serum antibody for a particular epitope, followed by immunocomplexes binding to capture antibody on the test line. With the accumulation of target antibody, captured probes served as signal elements for fluorescent readout in a "turn off" mode, along with the fluorescence gradually weakened. The sensitivity and standard calibration curve of the QB-CICA were quantified using swine sera as negative control (n = 200) and artificial infected swine sera (n = 80) compared with a commercial ELISA kit. Besides, Trichinella spiralis-antibody targeting test ability of the QB-CICA, instead of other parasites or viruses antibodies (n = 10), was evaluated. RESULTS: The QB-CICA exhibited a good linear range, a low detection limit of 189.92 ng mL-1 and 100% selectivity that was higher than commercial ELISA kit (90%), as well as the same serological positive rate (100%) with commercial ELISA kit in different infection dose models. CONCLUSION: Taking advantage of its simplicity, short response time (25 min), sensitivity and specificity, the proposed QB-CICA has potential applications for parasite-related antibody monitoring in food safety and clinical diagnosis fields.
Subject(s)
Antibodies, Helminth/analysis , Antibodies, Monoclonal/immunology , Chromatography, Affinity/methods , Nanoparticles/chemistry , Quantum Dots/chemistry , Trichinella spiralis/immunology , Trichinellosis/diagnosis , Trichinellosis/immunology , Animals , Antibodies, Helminth/blood , Antibodies, Helminth/immunology , Nanoparticles/ultrastructure , Quantum Dots/ultrastructure , Swine , Trichinellosis/parasitologyABSTRACT
BACKGROUND: Carbon dots (CDs) emitting near-infrared fluorescence were recently synthesized from green leaves. However, the Hg2+ detection of CDs was limited because of the insufficient water solubility, low fluorescence and poor stability. METHODS: Dual fluorescence emission water-soluble CD (Dual-CD) was prepared through a solvothermal method from holly leaves and low toxic PEI1.8k. PEG was further grafted onto the surface to improve the water solubility and stability. RESULTS: The Dual-CD solution can emit 487 nm and 676 nm fluorescence under single excitation and exhibit high quantum yield of 16.8%. The fluorescence at 678 nm decreased remarkably while the emission at 470 nm was slightly affected by the addition of Hg2+. The ratiometric Hg2+ detection had a wide linear range of 0-100 µM and low detection limit of 14.0 nM. In A549 cells, there was a good linear relation between F487/F676 and the concentration of Hg2+ in the range of 0-60 µM; the detection limit was 477 nM. Furthermore, Dual-CD showed visual fluorescence change under Hg2+. CONCLUSION: Dual-CD has ratiometric responsiveness to Hg2+ and can be applied for quantitative Hg2+ detection in living cells.
Subject(s)
Carbon/chemistry , Ilex/chemistry , Mercury/analysis , Plant Leaves/chemistry , Quantum Dots/chemistry , Water/chemistry , A549 Cells , Cell Survival , Humans , Ions , Optical Phenomena , Photoelectron Spectroscopy , Quantum Dots/ultrastructure , Spectrometry, Fluorescence , Spectrophotometry, UltravioletABSTRACT
BACKGROUND: It is well known that smoking is harmful to health; however, it can also ameliorate anxiety. To date, it is unclear whether any nanoparticles found in cigarette mainstream smoke (CS) contribute to this effect. AIM: The aim of this study was to assess the particle composition of CS to identify novel anti-anxiety components. METHODS: Carbon dots (CDs) from CS (CS-CDs) were characterised using high-resolution transmission electron microscopy, Fourier-transform infrared, ultraviolet, fluorescence, X-ray photoelectron spectroscopy, X-ray diffraction and high-performance liquid chromatography. The anti-anxiety effects of CS-CDs in mouse models were evaluated and confirmed with the elevated plus maze and open-field tests. RESULTS: The quantum yield of CS-CDs was 13.74%, with a composition of C, O, and N. In addition, the surface groups contained O-H, C-H, C=O, C-N, N-H, C-O-C, and COO- bonds. Acute toxicity testing revealed that CS-CDs had low in vitro and in vivo toxicity within a certain concentration range. The results of the elevated plus maze and open-field tests showed that CS-CDs had a significant anti-anxiety effect and a certain sedative effect in mice. The mechanism of these effects may be related to the decrease in glutamate levels and promotion of norepinephrine production in the mouse brain, and the decrease in dopamine in mouse serum due to CS-CDs. CONCLUSION: CS-CDs may have anti-anxiety and certain sedative effects. This study provides a new perspective for a more comprehensive understanding of the components, properties, and functions of CS. Furthermore, it offers a novel target for the development of smoking cessation treatments, such as nicotine replacement therapy.
Subject(s)
Behavior, Animal , Carbon/chemistry , Cigarette Smoking/adverse effects , Endocrine System/metabolism , Neurotransmitter Agents/metabolism , Quantum Dots/chemistry , Water/chemistry , Adrenocorticotropic Hormone/blood , Animals , Anxiety/blood , Anxiety/pathology , Brain/metabolism , Brain/pathology , Chromatography, High Pressure Liquid , Corticosterone/blood , Corticotropin-Releasing Hormone/blood , Dopamine/blood , Male , Mice , Mice, Inbred ICR , Photoelectron Spectroscopy , Quantum Dots/ultrastructure , RAW 264.7 Cells , Spectrometry, Fluorescence , Spectroscopy, Fourier Transform Infrared , Spectrum Analysis, Raman , Toxicity Tests, Acute , X-Ray DiffractionABSTRACT
Chiral carbon dots (CDs) integrated the advantages of achiral CDs and the unique chiral property, which expand the prospect of the biological applications of CDs. However, the structure control and the origin of chirality for chiral CDs remain unclear. Herein, chiral CDs were obtained by thermal polymerization of chiral amino acids and citric acid, and their handedness of chirality could be controlled by adjusting the reaction temperature, which leads to different kinds of surface modifications. With aliphatic amino acids as a chiral source, all of the CDs that reacted at different temperatures (90-200 °C) have the same handedness of the chiral source. But with aromatic amino acids as a chiral source, CDs with maintained or inversed handedness compared with the chiral source could be obtained by adjusting the reaction temperature. Below a temperature of 120 °C, the chiral source was modified with CDs by esterification and transferred the handedness of chirality; at high temperatures (above 150 °C), which mainly connected by amidation accompanying with the formation of rigid structure generated by the π conjugation between the aromatic nucleus of chiral source and the carbon core of CDs, caused the inversing of the chiral signal. Further, we investigated the chiral effects of CDs on the glucose oxidase activity for a highly sensitive electrochemical biosensor.
Subject(s)
Amino Acids/chemistry , Biosensing Techniques/methods , Glucose Oxidase/chemistry , Glucose/analysis , Quantum Dots/chemistry , Carbon/chemistry , Citric Acid/chemistry , Enzyme Stability , Esterification , Models, Molecular , Polymerization , Quantum Dots/ultrastructure , Stereoisomerism , Surface PropertiesABSTRACT
Cadmium Oxide nanoparticles have the lowest toxicity when compared to nanoparticles of other semiconductors and they are not detrimental to human and mammalian cells, thereby making them candidates for targeting cancer cells. Synadenium cupulare plant extracts were used to synthesize CdO/CdCO3 nanocomposite using cadmium nitrate tetrahydrate 98% as a precursor salt. The resultant nanoparticles were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy, ultraviolet visible spectroscopy, and Fourier transform infrared spectroscopy (FTIR). The nanoparticles were then screened for effect on breast cancer cell lines (MCF-7 and MDA MB-231) and Vero cell line to determine their growth inhibition effect. Cytotoxicity effect was evaluated using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. XRD showed the peaks of monteponite CdO and otavite CdCO3 nanoparticles. TEM results showed irregular and spherical particles of varying sizes, whilst SEM revealed a non-uniform morphology. FTIR results showed peaks of functional groups which are present in some of the phytochemical compounds found in S. cupulare, and point to the presence of CdO. Annealed CdO/CdCO3 NPs showed selectivity for MCF7 and MDA MB231 in comparison to Vero cell line, thereby supporting the hypothesis that cadmium oxide nanoparticles inhibit growth of cancerous cells more than non-cancerous cells.
Subject(s)
Breast Neoplasms/drug therapy , Nanocomposites/chemistry , Nanocomposites/therapeutic use , Quantum Dots/chemistry , Quantum Dots/therapeutic use , Animals , Breast Neoplasms/pathology , Cadmium/chemistry , Cadmium Compounds/chemistry , Carbonates/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Chlorocebus aethiops , Female , Humans , MCF-7 Cells , Magnoliopsida/chemistry , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Nanocomposites/ultrastructure , Oxides/chemistry , Photoelectron Spectroscopy , Plant Extracts/chemistry , Quantum Dots/ultrastructure , Spectroscopy, Fourier Transform Infrared , Vero Cells , X-Ray DiffractionABSTRACT
Requirement for medication from pathogenic human viruses and cancer diseases are urgently considered, while, numerous reports were focused on investigating easily manufactured and excellently effective therapeutic reagents. Herein, CQDs were prepared with size of 2.1 nm from both of carrageenan and pullulan. CQDs nucleated from pullulan showed higher anti-proliferative effects against cancer cells, while, treatment with 100 µg/mL of CQDs colloids originated from pullulan and carrageenan separately resulted in diminishing of cancer cell viability percent to be 42.1 & 58.7%, respectively. Plaque reduction assay was also affirmed that, 2.5 µg/L of both of pullulan and carrageenan based CQDs exhibited viral inhibition with percent of 44.3& 59.5%, respectively. As a conclusion, pullulan showed seniority over carrageenan in nucleation of CQDs with higher anticancer activities. While, estimation of antiviral performance of the prepared CQDs confirmed the priority of carrageenan compared to pullulan in preparation of CQDs as antiviral laborer.
Subject(s)
Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Quantum Dots/chemistry , Quantum Dots/therapeutic use , Apoptosis/drug effects , Carbon/chemistry , Carrageenan/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Drug Evaluation, Preclinical , Drug Screening Assays, Antitumor , Glucans/chemistry , Green Chemistry Technology , Humans , Microscopy, Electron, Transmission , Middle East Respiratory Syndrome Coronavirus/drug effects , Quantum Dots/ultrastructure , Viral Plaque AssayABSTRACT
Glutathione (GSH) is a thiol that plays a significant role in nutrient metabolism, antioxidant defense and the regulation of cellular events. GSH deficiency is related to variety of diseases, so it is useful to develop novel approaches for GSH evaluation and detection. In this study we used nitrogen and phosphorus co-doped carbon dot-gold nanoparticle (NPCD-AuNP) composites to fabricate a simple and selective fluorescence sensor for GSH detection. We employed the reductant potential of the nitrogen and phosphorus co-doped carbon dots (NPCDs) themselves to form AuNPs, and subsequently NPCD-AuNP composites from Au3+. The composites were characterized by using a range of spectroscopic and electron microscopic techniques, including electrophoretic light scattering and X-ray diffraction. The overlap of the fluorescence emission spectrum of NPCDs and the absorption spectrum of AuNPs resulted in an effective inner filter effect (IFE) in the composite material, leading to a quenching of the fluorescence intensity. In the presence of GSH, the fluorescence intensity of the composite was recovered, which increased proportionally to increasing the GSH concentration. In addition, our GSH sensing method showed good selectivity and sensing potential in human serum with a limit of detection of 0.1 µM and acceptable results.
Subject(s)
Carbon/chemistry , Glutathione/analysis , Gold/chemistry , Metal Nanoparticles/chemistry , Quantum Dots/chemistry , Glutathione/blood , Metal Nanoparticles/ultrastructure , Photoelectron Spectroscopy , Quantum Dots/ultrastructure , Spectrometry, Fluorescence , Spectrophotometry, Ultraviolet , X-Ray DiffractionABSTRACT
Background: Azo dyes are the most widely used synthetic colorants in the textile, food, pharmaceutical, cosmetic, and other industries, accounting for nearly 70% of all dyestuffs consumed. Recently, much research attention has been paid to efficient monitoring of these hazardous chemicals and their related metabolites because of their potentially harmful effect on environmental issues. In contrast to the complex and expensive instrumental procedures, the detection system based on the quantum dots (QDs) with the superior optochemical properties provides a new era in the pollution sensing and prevention. Methods: We have developed a QD-enzyme hybrid system to probe methyl red (MR) in aqueous solutions using a fluorescence quenching procedure. Results: The azoreductase enzyme catalyzed the reduction of azo group in MR, which can efficiently decrease the Förster resonance energy transfer between the QDs and MR molecules. The correlation between the QDs photoluminescence recovery and MR enzymatic decolorization at the neutral phosphate buffer permitted the creation of a fluorescence quenching-based sensor. The synthesized biosensor can be used for the accurate detection of MR in a linear calibration over MR concentrations of 5-84 µM, with the limit of detection of 0.5 µM in response time of three minutes. Conclusion: Our findings revealed that this fluorometric sensor has the potential to be successfully applied for monitoring a wide linear range of MR concentration with the relative standard deviation of 4% rather than the other method.
Subject(s)
Azo Compounds/analysis , Nitroreductases/chemistry , Quantum Dots/chemistry , Azo Compounds/chemistry , Biosensing Techniques/methods , Fluorescence , Quantum Dots/ultrastructure , Water Pollutants, Chemical/analysisABSTRACT
BACKGROUND: The excess production of reactive oxygen species (ROS) after traumatic spinal cord injury (TSCI) has been identified as a leading cause of secondary injury, which can significantly exacerbate acute damage in the injured spinal cord. Thus, scavenging of ROS has emerged as an effective route to ameliorate secondary spinal cord injury. PURPOSE: Selenium-doped carbon quantum dots (Se-CQDs) with the ability to scavenge reactive oxygen species were prepared and used for efficiently ameliorating secondary injury in TSCI. METHODS: Water-soluble Se-CQDs were easily synthesized via hydrothermal treatment of l-selenocystine. The chemical structure, size, and morphology of the Se-CQDs were characterized in detail. The biocompatibility and protective effects of the Se-CQDs against H2O2-induced oxidative damage were investigated in vitro. Moreover, the behavioral test, bladder function, histological observation, Western blot were used to investigate the neuroprotective effect of Se-CQDs in a rat model of contusion TSCI. RESULTS: The obtained Se-CQDs exhibited good biocompatibility and remarkable protective effect against H2O2-induced oxidative damage in astrocytes and PC12 cells. Moreover, Se-CQDs displayed marked anti-inï¬ammatory and anti-apoptotic activities, which thereby reduced the formation of glial scars and increased the survival of neurons with unscathed myelin sheaths in vivo. As a result, Se-CQDs were capable of largely improving locomotor function of rats with TSCI. CONCLUSION: This study suggests that Se-CQDs can be used as a promising therapeutic platform for ameliorating secondary injury in TSCI.
Subject(s)
Carbon/chemistry , Quantum Dots/chemistry , Reactive Oxygen Species/metabolism , Selenium/pharmacology , Spinal Cord Injuries/pathology , Animals , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Antioxidants/pharmacology , Apoptosis/drug effects , Astrocytes/drug effects , Astrocytes/pathology , Disease Models, Animal , Female , Mice , Motor Activity/drug effects , Neuroglia/drug effects , Neuroglia/pathology , Neuroprotection/drug effects , Neuroprotective Agents/pharmacology , Neuroprotective Agents/therapeutic use , PC12 Cells , Quantum Dots/ultrastructure , Rats , Rats, Sprague-Dawley , Recovery of Function/drug effects , Spinal Cord/drug effects , Spinal Cord/pathology , Spinal Cord/physiopathology , Spinal Cord Injuries/drug therapy , Spinal Cord Injuries/physiopathologyABSTRACT
INTRODUCTION: The charcoal processed product of Paeoniae Radix Alba (PRA), PRA Carbonisata (PRAC), has long been used for its hepatoprotective effects. However, the material basis and mechanism of action of PRAC remain unclear. AIM: To explore the hepatoprotective effects of Paeoniae Radix Alba Carbonisata-derived carbon dots (PRAC-CDs). METHODS: PRAC-CDs were characterized using transmission electron microscopy, high-resolution transmission electron microscopy, ultraviolet, fluorescence, Fourier transform infrared and X-ray photoelectron spectroscopy, X-ray diffraction, and high-performance liquid chromatography. The hepatoprotective effect of PRAC-CDs was evaluated and confirmed using the classic carbon tetrachloride acute liver injury model. RESULTS: PRAC-CDs averaged 1.0-2.4 nm in size and exhibited a quantum yield of 5.34% at a maximum excitation wavelength of 320 nm and emission at 411 nm. PRAC-CDs can reduce the ALT and AST levels of mice with carbon tetrachloride-induced acute liver injury and have a mitigating effect on the rise in TBA and TBIL. More interestingly, PRAC-CDs can significantly reduce MDA and increase SOD levels, demonstrating that PRAC-CDs can improve the body's ability to scavenge oxygen free radicals and inhibit free radical-induced liver cell lipid peroxidation, thereby preventing liver cell damage. CONCLUSION: These results demonstrate the remarkable hepatoprotective effects of PRAC-CDs against carbon tetrachloride-induced acute liver injury, which provide new insights into potential biomedical and healthcare applications of CDs.
Subject(s)
Carbon/pharmacology , Drugs, Chinese Herbal/pharmacology , Liver/drug effects , Protective Agents/pharmacology , Quantum Dots/chemistry , Animals , Bile Ducts/drug effects , Carbon Tetrachloride , Cell Death/drug effects , Charcoal , Chromatography, High Pressure Liquid , Liver/metabolism , Male , Malondialdehyde/metabolism , Mice , Photoelectron Spectroscopy , Quantum Dots/ultrastructure , RAW 264.7 Cells , Superoxide Dismutase/metabolism , Transaminases/metabolismABSTRACT
A nanohybrid prepared from green source (nanocellulose, NC) and nitrogen, sulfur co-doped graphene quantum dots (N, S@GQDs) was prepared for the electrochemical detection of olanzapine (OLZ), atypical antipsychotic primarily used to treat schizophrenia and bipolar disorder. Polar groups on the surface of NC and N, S@GQDs provide more anchoring sites for adsorption of OLZ onto the electrode surface. In addition, it provides high conductivity, good mechanical strength, large surface area, and excellent electrical conductivity. The nanocomposite was characterized morphologically and electrochemically by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDX), transmission electron microscope (TEM), electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and square wave adsorptive stripping voltammetry (SWAdSV). Under the optimized conditions, the modified electrode has a good response in the range of 1.5-90.0 × 10-8 M with LOD of 0.5 × 10-8 M. The proposed electrode offers high sensitivity, selectivity, and reliability towards OLZ detection. The SWAdSV was used to determine OLZ in pharmaceutical tablets, human plasma and urine with good recoveries % and reasonable RSD% values.
Subject(s)
Body Fluids/chemistry , Cellulose/chemistry , Graphite/chemistry , Nanocomposites/chemistry , Nitrogen/chemistry , Olanzapine/analysis , Quantum Dots/chemistry , Sulfur/chemistry , Calibration , Dielectric Spectroscopy , Electric Conductivity , Electrochemical Techniques , Electrodes , Humans , Limit of Detection , Nanocomposites/ultrastructure , Olanzapine/blood , Olanzapine/therapeutic use , Olanzapine/urine , Oxidation-Reduction , Quantum Dots/ultrastructure , Reproducibility of Results , Schizophrenia/drug therapy , Spectrometry, Fluorescence , Spectrophotometry, Ultraviolet , Spectroscopy, Fourier Transform Infrared , Spectrum Analysis, Raman , Surface Properties , Tablets , X-Ray DiffractionABSTRACT
The shortcomings in Boron neutron capture therapy (BNCT) and Hyperthermia for killing the tumor cell desired for the synthesis of a new kind of material suitable to be first used in BNCT and later on enable the conditions for Hyperthermia to destroy the tumor cell. The desire led to the synthesis of large band gap semiconductor nano-size Boron-10 enriched crystals of hexagonal boron nitride (10BNNCs). The contents of 10BNNCs are analyzed with the help of x-ray photoelectron spectroscopy (XPS) and counter checked with Raman and XRD. The 10B-contents in 10BNNCs produce 7Li and 4He nuclei. A Part of the 7Li and 4He particles released in the cell is allowed to kill the tumor (via BNCT) whereas the rest produce electron-hole pairs in the semiconductor layer of 10BNNCs suggested to work in Hyperthermia with an externally applied field.
Subject(s)
Boron Compounds/chemical synthesis , Boron Neutron Capture Therapy/methods , Nanoparticles/chemistry , Animals , Boron/chemistry , Boron/therapeutic use , Boron Compounds/chemistry , Boron Compounds/therapeutic use , Humans , Hyperthermia, Induced/methods , Isotopes/chemistry , Isotopes/therapeutic use , Microscopy, Electron, Transmission , Nanoparticles/therapeutic use , Nanoparticles/ultrastructure , Nanotechnology , Neoplasms/radiotherapy , Neoplasms/therapy , Photoelectron Spectroscopy , Quantum Dots/chemistry , Quantum Dots/therapeutic use , Quantum Dots/ultrastructure , Spectrum Analysis, Raman , X-Ray DiffractionABSTRACT
While carbon-based materials have spearheaded numerous breakthroughs in biomedicine, they also have procreated many logical concerns on their overall toxicity. Carbon dots (CDs) as a respectively new member have been extensively explored in nucleus directed delivery and bioimaging due to their intrinsic fluorescence properties coupled with their small size and surface properties. Although various in vitro/in vivo studies have shown that CDs are mostly biocompatible, sufficient information is lacking regarding genotoxicity of them and underlying mechanisms. This study aims to analyze the real-time cytotoxicity of super tiny CDs (2.05 ± 0.22 nm) on human breast cancer cells (MCF7) and human primary dermal fibroblast cell cultures (HDFa) by xCELLigence analysis system for further evaluating their genotoxicity and clastogenicity to evaluate the anti-tumor potential of CDs on breast adenocarcinoma. As combined with flow cytometry studies, comet assay and cytokinesis-block micronucleus assay suggest that the CDs can penetrate to the cell nuclei, interact with the genetic material, and explode DNA damage and G0/G1 phase arrest in cancer cells even at very low concentrations (0.025 ppm) which provide a strong foundation for the design of potentially promising CD-based functional nanomaterials for DNA-damage induced treatment in cancer therapy.
Subject(s)
Antineoplastic Agents/pharmacology , Carbon/toxicity , Cell Cycle Checkpoints , DNA Damage , Quantum Dots/toxicity , Cell Cycle Checkpoints/drug effects , Dynamic Light Scattering , Humans , Hydrodynamics , MCF-7 Cells , Micronucleus Tests , Mutagens/toxicity , Particle Size , Photoelectron Spectroscopy , Quantum Dots/ultrastructure , Spectroscopy, Fourier Transform Infrared , Time FactorsABSTRACT
In the present research, we prepared new glycodendrimer containing ß-cyclodextrin (ß-CD) in three steps. At first, graphene quantum dots (GQDs) synthesized through pyrolysis of the citric acid (CA). Then the polyamidoamine (PAMAM) dendrimer was grown from the surface of the modified GQDs (GQDs-PAMAM). Finally, the prepared GQDs-PAMAM was functionalized with ß-CD to obtain the glycodendrimer (GQDs-PAMAM-ß-CD). The synthesized glycodendrimer characterized using several techniques. The phenol-sulfuric acid test obtained the amount of the ß-CD about 30.37 %. 61.2 % of doxorubicin (DOX) was loaded in the prepared glycodendrimer. DOX@GQDs-PAMAM-ß-CD displayed the pH-sensitive drug release profile, which fitted the Higuchi kinetic model. The biological test outcomes showed that the GQDs-PAMAM-ß-CD is a safe carrier with good capability in penetration to the cancer cells. Moreover, DOX@GQDs-PAMAM-ß-CD exhibited more efficiency in the killing of the cancer cells compared to neat DOX. Obtained results suggested that prepared glycodendrimer could be a potential nanosystem for breast cancer treatment.