Browse
Submit Data
Databases
API
Help

Dataset Information

27 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Cross-Linked Polyamide Chains Enhanced the Fluorescence of Polymer Carbon Dots.

ABSTRACT: Carbon dots (CDs) have attracted tremendous attention for their outstanding advantages in luminescence. Here, ?-amino-substituted lysine derivatives with the determined chemical structure were employed as precursors to obtain bright and highly stable fluorescent CDs through a facile hydrothermal route. The relationships among the chemical structure of precursors, CD fluorescence, and particle size were investigated. The results indicated that increased numbers of functional groups in precursors could promote the degree of cross-linking and lead to a smaller size, better fluorescent properties, and stronger stability of CDs. The C-CDs that were prepared from lysine derivatives with most functional groups showed excitation-dependent dual excitation and dual emission (DE²), high-stability luminescence, strong resistance to photobleaching, and high selectivity to Fe³⁺ and could be used as a sensitive probe for Fe³⁺ detection.

SUBMITTER: Yang S

PROVIDER: S-EPMC7161025 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Cross-Linked Polyamide Chains Enhanced the Fluorescence of Polymer Carbon Dots.

Yang Shouning S Zhang Yanmin Y Xue Yuyan Y Lu Sijia S Yang Huayan H Yang Lin L Ding Chuanfan C Yu Shaoning S

ACS omega 20200401 14

Carbon dots (CDs) have attracted tremendous attention for their outstanding advantages in luminescence. Here, α-amino-substituted lysine derivatives with the determined chemical structure were employed as precursors to obtain bright and highly stable fluorescent CDs through a facile hydrothermal route. The relationships among the chemical structure of precursors, CD fluorescence, and particle size were investigated. The results indicated that increased numbers of functional groups in precursors ...[more]

PMID: 32309732

Similar Datasets

Enhanced Fluorescence Properties of Carbon Dots in Polymer Films.

Project description:Carbon dots of small carbon nanoparticles surface-functionalized with 2,2'-(ethylenedioxy)bis(ethylamine) (EDA) were synthesized, and the as-synthesized sample was separated on an aqueous gel column to obtain fractions of the EDA-carbon dots with different fluorescence quantum yields. As already discussed in the literature, the variations in fluorescence performance among the fractions were attributed to the different levels and/or effectiveness of the surface functionalization-passivation in the carbon dots. These fractions, as well as carbon nanoparticles without any deliberate surface functionalization, were dispersed into poly(vinyl alcohol) (PVA) for composite films. In the PVA film matrix, the carbon dots and nanoparticles exhibited much enhanced fluorescence emissions in comparison with their corresponding aqueous solutions. The increased fluorescence quantum yields in the films were determined quantitatively by using a specifically designed and constructed film sample holder in the emission spectrometer. The observed fluorescence decays of the EDA-carbon dots in film and in solution were essentially the same, suggesting that the significant enhancement in fluorescence quantum yields from solution to film is static in nature. Mechanistic implications of the results, including a rationalization in terms of the compression effect on the surface passivation layer (similar to a soft corona) in carbon dots when embedded in the more restrictive film environment resulting in more favorable radiative recombinations of the carbon particle surface-trapped electrons and holes, and also potential technological applications of the brightly fluorescent composite films are highlighted and discussed.

| S-EPMC5268499 | biostudies-literature

Multicolor polymeric carbon dots: synthesis, separation and polyamide-supported molecular fluorescence.

Project description:Multicolor carbon dots (CDs) have been developed recently and demonstrate great potential in bio-imaging, sensing, and LEDs. However, the fluorescence mechanism of their tunable colors is still under debate, and efficient separation methods are still challenging. Herein, we synthesized multicolor polymeric CDs through solvothermal treatment of citric acid and urea in formamide. Automated reversed-phase column separation was used to achieve fractions with distinct colors, including blue, cyan, green, yellow, orange and red. This work explores the physicochemical properties and fluorescence origins of the red, green, and blue fractions in depth with combined experimental and computational methods. Three dominant fluorescence mechanism hypotheses were evaluated by comparing time-dependent density functional theory and molecular dynamics calculation results to measured characteristics. We find that blue fluorescence likely comes from embedded small molecules trapped in carbonaceous cages, while pyrene analogs are the most likely origin for emission at other wavelengths, especially in the red. Also important, upon interaction with live cells, different CD color fractions are trafficked to different sub-cellular locations. Super-resolution imaging shows that the blue CDs were found in a variety of organelles, such as mitochondria and lysosomes, while the red CDs were primarily localized in lysosomes. These findings significantly advance our understanding of the photoluminescence mechanism of multicolor CDs and help to guide future design and applications of these promising nanomaterials.

| S-EPMC8179321 | biostudies-literature

Full-Color Emission Polymer Carbon Dots with Quench-Resistant Solid-State Fluorescence.

Project description:Polymer carbon dots (PCDs) represent a new class of carbon dots (CDs) possessing sub-fluorophores and unique polymer-like structures. However, like small molecule dyes and traditional CDs, PCDs often suffer from self-quenching effect in solid state, limiting their potential applications. Moreover, it is hard to prepare PCDs that have the same chemical structure, exhibiting full-color emission under one fixed excitation wavelength by only modulating the concentration of the PCDs. Herein, self-quenching-resistant solid-state fluorescent polymer carbon dots (SSFPCDs) are prepared, which exhibit strong red SSF without any other additional solid matrices, while having a large production yield (≈89%) and a considerable quantum yield of 8.50%. When dispersed in water or solid matrices in gradient concentrations, they can exhibit yellow, green, and blue fluorescence, realizing the first SSFPCDs with the same chemical structure emitting in full-color range by changing the ratio of SSFPCDs to the solid matrices.

| S-EPMC5737236 | biostudies-literature

Tannin-Mn coordination polymer coated carbon quantum dots nanocomposite for fluorescence and magnetic resonance bimodal imaging.

Project description:The MR/FI bimodal imaging has attracted widely studied due to combining the advantages of MRI and FI can bridge gaps in sensitivity and depth between these two modalities. Herein, a novel MR/FI bimodal imaging probe is facile fabricated by coating the Mn-phenolic coordination polymer on the surface of the carbon quantum dots. The structure of the as-prepared nanocomposite probe is carefully validated via SEM, TEM, and XPS. The content of Mn2+ is calculated through the EDS and TGA. The quantum yield (QY) and emission wavelength of the probe are about 7.24% and 490 nm, respectively. The longitudinal r1 value (2.43 mM-1 s-1) with low r2/r1 (4.45) of the probe is obtained. Subsequently, fluorescence and MR imaging are performed. The metabolic pathways in vivo are inferred by studying the bio-distribution of the probe in major organs. Thus, these results indicate that probe would be an excellent dual-modal imaging probe for enhanced MR imaging and fluorescence imaging. MR/FI bimodal imaging probe is built via in-situ coated Mn-phenolic coordination polymer on the surface of the carbon quantum dots. The in vitro and vivo image property of the probe is evaluated.

| S-EPMC8786750 | biostudies-literature

Design and Synthesis of Core-Shell Carbon Polymer Dots with Highly Stable Fluorescence in Polymeric Materials.

Project description:In recent years, fluorescent carbon dots have attracted great attention due to their good luminescence and low toxicity. Here, blue fluorescent core-shell structured carbon polymer dots (CPDs) with high stability under a wide range of pH values, long storage time and excellent fluorescence in various solvents and even in solid state were prepared by hydrothermal synthesis of dendritic tris(2-aminoethyl)amine (TAEA) and citric acid. The CPDs core structure provides strong fluorescent luminescence, a shell structure of the core possesses high amount of dendritic primary amino groups connected by ethylene groups to the core. This unique structure prevents aggregation of the cores and self-quenching effect of CPDs. As a result, the CPDs have high fluorescence in both aqueous and hydrophobic solutions and even as pure solid-state powder. In addition, the CPDs are also insensitive to pH of solutions, and the fluorescence intensity of the solution was stable in the pH range of 4-14. The CPDs embedded polymer films and fibers revealed excellent fluorescent properties.

| S-EPMC8318204 | biostudies-literature

Carbon Quantum Dots for Zebrafish Fluorescence Imaging.

Project description:Carbon quantum dots (C-QDs) are becoming a desirable alternative to metal-based QDs and dye probes owing to their high biocompatibility, low toxicity, ease of preparation, and unique photophysical properties. Herein, we describe fluorescence bioimaging of zebrafish using C-QDs as probe in terms of the preparation of C-QDs, zebrafish husbandry, embryo harvesting, and introduction of C-QDs into embryos and larvae by soaking and microinjection. The multicolor of C-QDs was validated with their imaging for zebrafish embryo. The distribution of C-QDs in zebrafish embryos and larvae were successfully observed from their fluorescence emission. the bio-toxicity of C-QDs was tested with zebrafish as model and C-QDs do not interfere to the development of zebrafish embryo. All of the results confirmed the high biocompatibility and low toxicity of C-QDs as imaging probe. The absorption, distribution, metabolism and excretion route (ADME) of C-QDs in zebrafish was revealed by their distribution. Our work provides the useful information for the researchers interested in studying with zebrafish as a model and the applications of C-QDs. The operations related zebrafish are suitable for the study of the toxicity, adverse effects, transport, and biocompatibility of nanomaterials as well as for drug screening with zebrafish as model.

| S-EPMC4488761 | biostudies-literature

Sustainable Development of Enhanced Luminescence Polymer-Carbon Dots Composite Film for Rapid Cd2+ Removal from Wastewater.

Project description:As a remedy for environmental pollution, a versatile synthetic approach has been developed to prepare polyvinyl alcohol (PVA)/nitrogen-doped carbon dots (CDs) composite film (PVA-CDs) for removal of toxic cadmium ions. The CDs were first synthesized using carboxymethylcellulose (CMC) of oil palms empty fruit bunch wastes with the addition of polyethyleneimine (PEI) and then the CDs were embedded with PVA. The PVA-CDs film possess synergistic functionalities through increasing the content of hydrogen bonds for chemisorption compared to the pure CDs. Optical analysis of PVA-CDs film was performed by ultraviolet-visible and fluorescence spectroscopy. Compared to the pure CDs, the solid-state PVA-CDs displayed a bright blue color with a quantum yield (QY) of 47%; they possess excitation-independent emission and a higher Cd2+ removal efficiency of 91.1%. The equilibrium state was achieved within 10 min. It was found that adsorption data fit well with the pseudo-second-order kinetic and Langmuir isotherm models. The maximum adsorption uptake was 113.6 mg g-1 at an optimal pH of 7. Desorption experiments showhe that adsorbent can be reused fruitfully for five adsorption-desorption cycles using 0.1 HCl elution. The film was successfully applied to real water samples with a removal efficiency of 95.34% and 90.9% for tap and drinking water, respectively. The fabricated membrane is biodegradable and its preparation follows an ecofriendly green route.

| S-EPMC7436165 | biostudies-literature

Room-temperature Magnetism in Carbon Dots and Enhanced Ferromagnetism in Carbon Dots-Polyaniline Nanocomposite.

Project description:Room temperature magnetic ordering is reported for very small carbon dots (CDs), mat-like polyaniline nanofibers (Mat-PANI) and a composite of CDs@Mat-PANI containing 0.315?wt% CDs. We have found saturation magnetization (M S ) of CDs, Mat-PANI and CDs@Mat-PANI at 5 (20/300) K equals to 0.0079 (0.0048/0.0019), 0.0116 (0.0065/0.0055) and 0.0349 (0.0085/0.0077) emu/g, respectively. The M S enhancement in CDs@Mat-PANI (200% and 40% at 5?K and 300?K, respectively) is attributed to electron transfer from Mat-PANI imine N-atoms to the encapsulated CDs. Changes in M S values reveal that 0.81 (0.08) electron/CD is transferred at 5 (300) K, which is supported by observation of CDs photoluminescence (PL) redshift while in CDs@Mat-PANI. Band-bending and bandgap-renormalization calculations are used to predict a redshift of 117?meV at 300?K as a result of the electron transfer, in excellent agreement with the PL data (110?meV). Raman, X-ray diffraction and X-ray photoelectron spectroscopy data are used to confirm the electron transfer process as well as the strong interaction of CDs with PANI within CDs@Mat-PANI, which increases the crystalline domain size of Mat-PANI from about 4.8?nm to 9.2?nm while reducing the tensile strain from about 6.2% to 1.8%.

| S-EPMC5438339 | biostudies-literature

Carbon Dots for Intracellular pH Sensing with Fluorescence Lifetime Imaging Microscopy.

Project description:The monitoring of intracellular pH is of great importance for understanding intracellular trafficking and functions. It has various limitations for biosensing based on the fluorescence intensity or spectra study. In this research, pH-sensitive carbon dots (CDs) were employed for intracellular pH sensing with fluorescence lifetime imaging microscopy (FLIM) for the first time. FLIM is a highly sensitive method that is used to detect a microenvironment and it can overcome the limitations of biosensing methods based on fluorescence intensity. The different groups on the CDs surfaces changing with pH environments led to different fluorescence lifetime values. The CDs aqueous solution had a gradual change from 1.6 ns to 3.7 ns in the fluorescence lifetime with a pH range of 2.6-8.6. Similar fluorescence lifetime changes were found in pH buffer-treated living cells. The detection of lysosomes, cytoplasm, and nuclei in living cells was achieved by measuring the fluorescence lifetime of CDs. In particular, a phasor FLIM analysis was used to improve the pH imaging. Moreover, the effects of the coenzymes, amino acids, and proteins on the fluorescence lifetime of CDs were examined in order to mimic the complex microenvironment inside the cells.

| S-EPMC7221822 | biostudies-literature

Squaraine-based polymer dots with narrow, bright near-infrared fluorescence for biological applications.

Project description:This article describes the design and development of squaraine-based semiconducting polymer dots (Pdots) that show large Stokes shifts and narrow-band emissions in the near-infrared (NIR) region. Fluorescent copolymers containing fluorene and squaraine units were synthesized and used as precursors for preparing the Pdots, where exciton diffusion and likely through-bond energy transfer led to highly bright and narrow-band NIR emissions. The resulting Pdots exhibit the emission full width at half-maximum of ?36 nm, which is ?2 times narrower than those of inorganic quantum dots in the same wavelength region (?66 nm for Qdot705). The squaraine-based Pdots show a high fluorescence quantum yield (QY) of 0.30 and a large Stokes shift of ?340 nm. Single-particle analysis indicates that the average per-particle brightness of the Pdots is ?6 times higher than that of Qdot705. We demonstrate bioconjugation of the squaraine Pdots and employ the Pdot bioconjugates in flow cytometry and cellular imaging applications. Our results suggest that the narrow bandwidth, high QY, and large Stokes shift are promising for multiplexed biological detections.

| S-EPMC4304448 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data