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1.
Metabolomics ; 20(4): 76, 2024 Jul 13.
Article in English | MEDLINE | ID: mdl-39002042

ABSTRACT

BACKGROUND: Aortic dissection (AD) significantly threated human cardiovascular health, extensive clinical-scientific research programs have been executed to uncover the pathogenesis and prevention. Unfortunately, no specific biomarker was identified for the causality or development of human AD. AIM OF REVIEW: Metabolomics, a high-throughput technique capable of quantitatively detecting metabolites, holds considerable promise in discovering specific biomarkers and unraveling the underlying pathways involved. Aiming to provide a metabolite prediction in human AD, we collected the metabolomics data from 2003 to 2023, and diligently scrutinized with the online system MetaboAnalyst 6.0. KEY SCIENTIFIC CONCEPTS OF REVIEW: Based on the data obtained, we have concluded the metabolic dynamics were highly correlated with human AD. Such metabolites (choline, serine and uridine) were frequently involved in the AD. Besides, the pathways, including amino acids metabolism and lipids metabolism, were also dysregulated in the disease. Due to the current limitation of metabolism analysis, the integrative omics data including genomics, transcriptomics, and proteomics were required for developing the specific biomarker for AD.


Subject(s)
Aortic Dissection , Biomarkers , Metabolomics , Humans , Biomarkers/metabolism , Aortic Dissection/metabolism , Aortic Dissection/diagnosis , Metabolomics/methods , Metabolome
2.
Clin Pharmacol Ther ; 115(6): 1316-1325, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38439157

ABSTRACT

The quality of warfarin treatment may be improved if management is guided by the use of models based upon pharmacokinetic-pharmacodynamic theory. A prospective, two-armed, single-blind, randomized controlled trial compared management aided by a web-based dose calculator (NextDose) with standard clinical care. Participants were 240 adults receiving warfarin therapy following cardiac surgery, followed up until the first outpatient appointment at least 3 months after warfarin initiation. We compared the percentage of time spent in the international normalized ratio acceptable range (%TIR) during the first 28 days following warfarin initiation, and %TIR and count of bleeding events over the entire follow-up period. Two hundred thirty-four participants were followed up to day 28 (NextDose: 116 and standard of care: 118), and 228 participants (114 per arm) were followed up to the final study visit. Median %TIR tended to be higher for participants receiving NextDose guided warfarin management during the first 28 days (63 vs. 56%, P = 0.13) and over the entire follow-up period (74 vs. 71%, P = 0.04). The hazard of clinically relevant minor bleeding events was lower for participants in the NextDose arm (hazard ratio: 0.21, P = 0.041). In NextDose, there were 89.3% of proposed doses accepted by prescribers. NextDose guided dose management in cardiac surgery patients requiring warfarin was associated with an increase in %TIR across the full follow-up period and fewer hemorrhagic events. A theory-based, pharmacologically guided approach facilitates higher quality warfarin anticoagulation. An important practical benefit is a reduced requirement for clinical experience of warfarin management.


Subject(s)
Anticoagulants , Bayes Theorem , Hemorrhage , International Normalized Ratio , Warfarin , Humans , Warfarin/administration & dosage , Warfarin/adverse effects , Female , Male , Anticoagulants/administration & dosage , Anticoagulants/adverse effects , Anticoagulants/pharmacokinetics , Aged , Middle Aged , Prospective Studies , Single-Blind Method , Hemorrhage/chemically induced , Standard of Care , Cardiac Surgical Procedures , Dose-Response Relationship, Drug , Precision Medicine/methods , Drug Dosage Calculations , Drug Monitoring/methods
3.
Curr Probl Cardiol ; 49(1 Pt A): 102040, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37595858

ABSTRACT

Aortic aneurysm and dissection are complicated diseases having both high prevalence and mortality. It is usually diagnosed at advanced stages and posing diagnostic and therapeutic challenges due to the limitations of current detecting methods for aortic dissection used in clinics. Metabonomics demonstrated its great potential capability in the early diagnosis and personalized treatment of several diseases. Emerging evidence suggests that metabolic disorders including amino acid metabolism, glycometabolism, and lipid metabolism disturbance are involved in the pathogenesis of aortic aneurysm and dissection by affecting multiple functional aortic cells. The purpose of this review is to provide new insights into the metabolism alterations and their related regulatory mechanisms with a focus on recent advances and findings and provide a theoretical basis for the diagnosis, prevention, and drug development for aortic aneurysm and dissection.


Subject(s)
Aortic Aneurysm , Aortic Dissection , Humans , Aortic Aneurysm/therapy , Aortic Aneurysm/complications , Aortic Dissection/diagnosis , Aortic Dissection/epidemiology , Aortic Dissection/etiology
4.
J Transl Med ; 21(1): 915, 2023 12 16.
Article in English | MEDLINE | ID: mdl-38104081

ABSTRACT

BACKGROUND: SARS-CoV-2, the pathogen of COVID-19, is a worldwide threat to human health and causes a long-term burden on the cardiovascular system. Individuals with pre-existing cardiovascular diseases are at higher risk for SARS-CoV-2 infection and tend to have a worse prognosis. However, the relevance and pathogenic mechanisms between COVID-19 and cardiovascular diseases are not yet completely comprehended. METHODS: Common differentially expressed genes (DEGs) were obtained in datasets of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) infected with SARS-CoV-2 and myocardial tissues from heart failure patients. Further GO and KEGG pathway analysis, protein-protein interaction (PPI) network construction, hub genes identification, immune microenvironment analysis, and drug candidate predication were performed. Then, an isoproterenol-stimulated myocardial hypertrophy cell model and a transverse aortic constriction-induced mouse heart failure model were employed to validate the expression of hub genes. RESULTS: A total of 315 up-regulated and 78 down-regulated common DEGs were identified. Functional enrichment analysis revealed mitochondrial metabolic disorders and extensive immune inflammation as the most prominent shared features of COVID-19 and cardiovascular diseases. Then, hub DEGs, as well as hub immune-related and mitochondria-related DEGs, were screened. Additionally, nine potential therapeutic agents for COVID-19-related cardiovascular diseases were proposed. Furthermore, the expression patterns of most of the hub genes related to cardiovascular diseases in the validation dataset along with cellular and mouse myocardial damage models, were consistent with the findings of bioinformatics analysis. CONCLUSIONS: The study unveiled the molecular networks and signaling pathways connecting COVID-19 and cardiovascular diseases, which may provide novel targets for intervention of COVID-19-related cardiovascular diseases.


Subject(s)
COVID-19 , Cardiovascular Diseases , Heart Failure , Induced Pluripotent Stem Cells , Mitochondrial Diseases , Humans , Animals , Mice , Cardiovascular Diseases/genetics , SARS-CoV-2 , Computational Biology , Disease Models, Animal , Inflammation/genetics
5.
Chem Rev ; 123(16): 10206-10257, 2023 Aug 23.
Article in English | MEDLINE | ID: mdl-37523660

ABSTRACT

Using compressive mechanical forces, such as pressure, to induce crystallographic phase transitions and mesostructural changes while modulating material properties in nanoparticles (NPs) is a unique way to discover new phase behaviors, create novel nanostructures, and study emerging properties that are difficult to achieve under conventional conditions. In recent decades, NPs of a plethora of chemical compositions, sizes, shapes, surface ligands, and self-assembled mesostructures have been studied under pressure by in-situ scattering and/or spectroscopy techniques. As a result, the fundamental knowledge of pressure-structure-property relationships has been significantly improved, leading to a better understanding of the design guidelines for nanomaterial synthesis. In the present review, we discuss experimental progress in NP high-pressure research conducted primarily over roughly the past four years on semiconductor NPs, metal and metal oxide NPs, and perovskite NPs. We focus on the pressure-induced behaviors of NPs at both the atomic- and mesoscales, inorganic NP property changes upon compression, and the structural and property transitions of perovskite NPs under pressure. We further discuss in depth progress on molecular modeling, including simulations of ligand behavior, phase-change chalcogenides, layered transition metal dichalcogenides, boron nitride, and inorganic and hybrid organic-inorganic perovskites NPs. These models now provide both mechanistic explanations of experimental observations and predictive guidelines for future experimental design. We conclude with a summary and our insights on future directions for exploration of nanomaterial phase transition, coupling, growth, and nanoelectronic and photonic properties.

6.
J Am Chem Soc ; 143(7): 2688-2693, 2021 Feb 24.
Article in English | MEDLINE | ID: mdl-33577287

ABSTRACT

We report here pressure induced nanocrystal coalescence of ordered lead chalcogenide nanocrystal arrays into one-dimensional (1D) and 2D nanostructures. In particular, atomic crystal phase transitions and mesoscale coalescence of PbS and PbSe nanocrystals have been observed and monitored in situ respectively by wide- and small-angle synchrotron X-ray scattering techniques. At the atomic scale, both nanocrystals underwent reversible structural transformations from cubic to orthorhombic at significantly higher pressures than those for the corresponding bulk materials. At the mesoscale, PbS nanocrystal arrays displayed a superlattice transformation from face-centered cubic to lamellar structures, while no clear mesoscale lattice transformation was observed for PbSe nanocrystal arrays. Intriguingly, transmission electron microscopy showed that the applied pressure forced both spherical nanocrystals to coalesce into single crystalline 2D nanosheets and 1D nanorods. Our results confirm that pressure can be used as a straightforward approach to manipulate the interparticle spacing and engineer nanostructures with specific morphologies and, therefore, provide insights into the design and functioning of new semiconductor nanocrystal structures under high-pressure conditions.

7.
J Am Chem Soc ; 142(14): 6505-6510, 2020 Apr 08.
Article in English | MEDLINE | ID: mdl-32202423

ABSTRACT

Understanding structural stability and phase transformation of nanoparticles under high pressure is of great scientific interest, as it is one of the crucial factors for design, synthesis, and application of materials. Even though high-pressure research on nanomaterials has been widely conducted, their shape-dependent phase transition behavior still remains unclear. Examples of phase transitions of CdS nanoparticles are very limited, despite the fact that it is one of the most studied wide band gap semiconductors. Here we have employed in situ synchrotron wide-angle X-ray scattering and transmission electron microscopy (TEM) to investigate the high-pressure behaviors of CdS nanoparticles as a function of particle shapes. We observed that CdS nanoparticles transform from wurtzite to rocksalt phase at elevated pressure in comparison to their bulk counterpart. Phase transitions also vary with particle shape: rod-shaped particles show a partially reversible phase transition and the onset of the structural phase transition pressure decreases with decreasing surface-to-volume ratios, while spherical particles undergo irreversible phase transition with relatively low phase transition pressure. Additionally, TEM images of spherical particles exhibited sintering-induced morphology change after high-pressure compression. Calculations of the bulk modulus reveal that spheres are more compressible than rods in the wurtzite phase. These results indicate that the shape of the particle plays an important role in determining their high-pressure properties. Our study provides important insights into understanding the phase-structure-property relationship, guiding future design and synthesis of nanoparticles for promising applications.

8.
Nano Lett ; 19(6): 3676-3683, 2019 06 12.
Article in English | MEDLINE | ID: mdl-31035748

ABSTRACT

Semiconductor nanomaterials with controlled morphologies and architectures are of critical importance for high-performance optoelectronic devices. However, the fabrication of such nanomaterials on polymer-based flexible electrodes is particularly challenging due to degradation of the flexible electrodes at a high temperature. Here we report the fabrication of nickel oxide nanopillar arrays (NiO x NaPAs) on a flexible electrode by vapor deposition, which enables highly efficient perovskite solar cells (PSCs). The NiO x NaPAs exhibit an enhanced light transmittance for light harvesting, prohibit exciton recombination, promote irradiation-generated hole transport and collection, and facilitate the formation of large perovskite grains. These advantageous features result in a high efficiency of 20% and 17% for the rigid and flexible PSCs, respectively. Additionally, the NaPAs show no cracking after 500 times of bending, consistent with the mechanic simulation results. This robust fabrication opens a new opportunity for the fabrication of a large area of high-performance flexible optoelectronic devices.

9.
Chem Rev ; 119(12): 7673-7717, 2019 06 26.
Article in English | MEDLINE | ID: mdl-31059242

ABSTRACT

Nanoparticle (NP) high pressure behavior has been extensively studied over the years. In this review, we summarize recent progress on the studies of pressure induced NP phase behavior, property, and applications. This review starts with a brief overview of high pressure characterization techniques, coupled with synchrotron X-ray scattering, Raman, fluorescence, and absorption. Then, we survey the pressure induced phase transition of NP atomic crystal structure including size dependent phase transition, amorphization, and threshold pressures using several typical NP material systems as examples. Next, we discuss the pressure induced phase transition of NP mesoscale structures including topics on pressure induced interparticle separation distance, NP coupling, and NP coalescence. Pressure induced new properties and applications in different NP systems are highlighted. Finally, outlooks with future directions are discussed.

10.
Nano Lett ; 19(4): 2614-2619, 2019 04 10.
Article in English | MEDLINE | ID: mdl-30848602

ABSTRACT

Design and engineering of highly efficient light-harvesting nanomaterial systems to emulate natural photosynthesis for maximizing energy conversion have stimulated extensive efforts. Here we present a new class of photoactive semiconductor nanocrystals that exhibit high-efficiency energy transfer for enhanced photocatalytic hydrogen production under visible light. These nanocrystals are formed through noncovalent self-assembly of In(III) meso-tetraphenylporphine chloride (InTPP) during microemulsion assisted nucleation and growth process. Through kinetic control, a series of uniform nanorods with controlled aspect ratio and high crystallinity have been fabricated. Self-assembly of InTPP porphyrins results in extensive optical coupling and broader coverage of the visible spectrum for efficient light harvesting. As a result, these nanocrystals display excellent photocatalytic hydrogen production and photostability under the visible light in comparison with the commercial InTPP porphyrin powders.


Subject(s)
Catalysis , Hydrogen/chemistry , Nanoparticles/chemistry , Porphyrins/chemistry , Emulsions/radiation effects , Energy Transfer/radiation effects , Light , Nanoparticles/radiation effects , Nanostructures/chemistry , Photosynthesis/radiation effects , Porphyrins/chemical synthesis
11.
J Am Chem Soc ; 141(13): 5392-5401, 2019 Apr 03.
Article in English | MEDLINE | ID: mdl-30848896

ABSTRACT

Due to remarkable electronic property, optical transparency, and mechanical flexibility, monolayer molybdenum disulfide (MoS2) has been demonstrated to be promising for electronic and optoelectronic devices. To date, the growth of high-quality and large-scale monolayer MoS2 has been one of the main challenges for practical applications. Here we present a MoS2-OH bilayer-mediated method that can fabricate inch-sized monolayer MoS2 on arbitrary substrates. This approach relies on a layer of hydroxide groups (-OH) that are preferentially attached to the (001) surface of MoS2 to form a MoS2-OH bilayer structure for growth of large-area monolayer MoS2 during the growth process. Specifically, the hydroxide layer impedes vertical growth of MoS2 layers along the [001] zone axis, promoting the monolayer growth of MoS2, constrains growth of the MoS2 monolayer only in the lateral direction into larger area, and effectively reduces sulfur vacancies and defects according to density functional theory calculations. Finally, the hydroxide groups advantageously prevent the MoS2 from interface oxidation in air, rendering high-quality MoS2 monolayers with carrier mobility up to ∼30 cm2 V-1 s-1. Using this approach, inch-sized uniform monolayer MoS2 has been fabricated on the sapphire and mica and high-quality monolayer MoS2 of single-crystalline domains exceeding 200 µm has been grown on various substrates including amorphous SiO2 and quartz and crystalline Si, SiC, Si3N4, and graphene This method provides a new opportunity for the monolayer growth of other two-dimensional transition metal dichalcogenides such as WS2 and MoSe2.

12.
Angew Chem Int Ed Engl ; 58(35): 11956-11966, 2019 Aug 26.
Article in English | MEDLINE | ID: mdl-30913343

ABSTRACT

Self-assembly of anisotropic plasmonic nanomaterials into ordered superstructures has become popular in nanoscience because of their unique anisotropic optical and electronic properties. Gold nanorods (GNRs) are a well-defined functional building block for fabrication of these superstructures. They possess important anisotropic plasmonic characteristics that result from strong local electric field and are responsive to visible and near-IR light. There are recent examples of assembling the GNRs into ordered arrays or superstructures through processes such as solvent evaporation and interfacial assembly. In this Minireview, recent progress in the development of the self-assembled GNR arrays is described, with focus on the formation of oriented GNR arrays on substrates. Key driving forces are discussed, and different strategies and self-assembly processes of forming oriented GNR arrays are presented. The applications of the oriented GNR arrays in optoelectronic devices are also overviewed, especially surface enhanced Raman scattering (SERS).

13.
iScience ; 11: 272-293, 2019 Jan 25.
Article in English | MEDLINE | ID: mdl-30639850

ABSTRACT

Nanoparticles (NPs) of controlled size, shape, and composition are important building blocks for the next generation of devices. There are numerous recent examples of organizing uniformly sized NPs into ordered arrays or superstructures in processes such as solvent evaporation, heterogeneous solution assembly, Langmuir-Blodgett receptor-ligand interactions, and layer-by-layer assembly. This review summarizes recent progress in the development of surfactant-assisted cooperative self-assembly method using amphiphilic surfactants and NPs to synthesize new classes of highly ordered active nanostructures. Driven by cooperative interparticle interactions, surfactant-assisted NP nucleation and growth results in optically and electrically active nanomaterials with hierarchical structure and function. How the approach works with nanoscale materials of different dimensions into active nanostructures is discussed in details. Some applications of these self-assembled nanostructures in the areas of nanoelectronics, photocatalysis, and biomedicine are highlighted. Finally, we conclude with the current research progress and perspectives on the challenges and some future directions.

14.
J Nanosci Nanotechnol ; 19(1): 465-469, 2019 Jan 01.
Article in English | MEDLINE | ID: mdl-30327057

ABSTRACT

Lead iodide based perovskites are promising optoelectronic materials ideal for solar cells. Recently emerged perovskite nanocrystals (NCs) offer more advantages including improved size-tunable band gap, structural stability, and solvent-based processing. Here we report a simple surfactant-assisted two-step synthesis to produce monodisperse PbI2 NCs which are then converted to methylammonium lead iodide perovskite NCs. Based on electron microscopy characterization, these NCs showed competitive monodispersity. Combined results from X-ray diffraction patterns, optical absorption, and photoluminescence confirmed the formation of high quality methylammonium lead iodide perovskite NCs. More importantly, by avoiding the use of hard-to-remove chemicals, the resulted perovskite NCs can be readily integrated in applications, especially solar cells through versatile solution/colloidal-based methods.

15.
Nano Lett ; 18(7): 4467-4472, 2018 07 11.
Article in English | MEDLINE | ID: mdl-29940113

ABSTRACT

Anisotropic nanoparticles, such as nanorods and nanoprisms, enable packing of complex nanoparticle structures with different symmetry and assembly orientation, which result in unique functions. Despite previous extensive efforts, formation of large areas of oriented or aligned nanoparticle structures still remains a great challenge. Here, we report fabrication of large-area arrays of vertically aligned gold nanorods (GNR) through a controlled evaporation deposition process. We began with a homogeneous suspension of GNR and surfactants prepared in water. During drop casting on silicon substrates, evaporation of water progressively enriched the concentrations of the GNR suspension, which induces the balance between electrostatic interactions and entropically driven depletion attraction in the evaporating solution to produce large-area arrays of self-assembled GNR on the substrates. Electron microscopy characterizations revealed the formation of layers of vertically aligned GNR arrays that consisted of hexagonally close-packed GNR in each layer. Benefiting from the close-packed GNR arrays and their smooth topography, the GNR arrays exhibited a surface-enhanced Raman scattering (SERS) signal for molecular detection at a concentration as low as 10-15 M. Because of the uniformity in large area, the GNR arrays exhibited exceptional detecting reproducibility and operability. This method is scalable and cost-effective and could lead to diverse packing structures and functions by variation of guest nanoparticles in the suspensions.

16.
Nat Commun ; 9(1): 2365, 2018 06 18.
Article in English | MEDLINE | ID: mdl-29915321

ABSTRACT

Metallic nanoparticles, such as gold and silver nanoparticles, can self-assemble into highly ordered arrays known as supercrystals for potential applications in areas such as optics, electronics, and sensor platforms. Here we report the formation of self-assembled 3D faceted gold nanoparticle supercrystals with controlled nanoparticle packing and unique facet-dependent optical property by using a binary solvent diffusion method. The nanoparticle packing structures from specific facets of the supercrystals are characterized by small/wide-angle X-ray scattering for detailed reconstruction of nanoparticle translation and shape orientation from mesometric to atomic levels within the supercrystals. We discover that the binary diffusion results in hexagonal close packed supercrystals whose size and quality are determined by initial nanoparticle concentration and diffusion speed. The supercrystal solids display unique facet-dependent surface plasmonic and surface-enhanced Raman characteristics. The ease of the growth of large supercrystal solids facilitates essential correlation between structure and property of nanoparticle solids for practical integrations.

17.
ACS Nano ; 12(4): 3796-3803, 2018 04 24.
Article in English | MEDLINE | ID: mdl-29611423

ABSTRACT

The use of nanoparticles as a potential building block for photosensitizers has recently become a focus of interest in the field of photocatalysis and photodynamic therapy. Porphyrins and their derivatives are effective photosensitizers due to extended π-conjugated electronic structure, high molar absorption from visible to near-infrared spectrum, and high singlet oxygen quantum yields as well as chemical versatility. In this paper, we report a synthesis of self-assembled porphyrin nanoparticle photosensitizers using zinc meso-tetra(4-pyridyl)porphyrin (ZnTPyP) through a confined noncovalent self-assembly process. Scanning electron microscopy reveals formation of monodisperse cubic nanoparticles. UV-vis characterizations reveal that optical absorption of the nanoparticles exhibits a red shift due to noncovalent self-assembly of porphyrins, which not only effectively increase intensity of light absorption but also extend light absorption broadly covering visible light for enhanced photodynamic therapy. Electron spin-resonance spectroscopy (ESR) studies show the resultant porphyrin nanoparticles release a high yield of singlet oxygen. Nitric oxide (NO) coordinates to central metal Zn ions to form stabilized ZnTPyP@NO nanoparticles. We show that under light irradiation ZnTPyP@NO nanoparticles release highly reactive peroxynitrite molecules that exhibit enhanced antibacterial photodynamic therapy (APDT) activity. The ease of the synthesis of self-assembled porphyrin nanoparticles and light-triggered release of highly reactive moieties represent a completely different photosensitizer system for APDT application.

18.
Nano Lett ; 18(1): 560-566, 2018 01 10.
Article in English | MEDLINE | ID: mdl-29277993

ABSTRACT

There has been a widespread interest in the preparation of self-assembled porphyrin nanostructures and their ordered arrays, aiming to emulate natural light harvesting processes and energy storage and to develop new nanostructured materials for photocatalytic process. Here, we report controlled synthesis of one-dimensional porphyrin nanostructures such as nanorods and nanowires with well-defined self-assembled porphyrin networks that enable efficient energy transfer for enhanced photocatalytic activity in hydrogen generation. Preparation of these one-dimensional nanostructures is conducted through noncovalent self-assembly of porphyrins confined within surfactant micelles. X-ray diffraction and transmission electron microscopy results reveal that these one-dimensional nanostructures contain stable single crystalline structures with controlled interplanar separation distance. Optical absorption characterizations show that the self-assembly enables effective optical coupling of porphyrins, resulting in much more enhanced optical absorption in comparison with the original porphyrin monomers, and the absorption bands red shift to more extensive visible light spectrum. The self-assembled porphyrin network facilitates efficient energy transfer among porphyrin molecules and the delocalization of excited state electrons for enhanced photocatalytic hydrogen production under visible light.

19.
Adv Mater ; 30(1)2018 Jan.
Article in English | MEDLINE | ID: mdl-29178388

ABSTRACT

Multiple-color-emissive carbon dots (CDots) have potential applications in various fields such as bioimaging, light-emitting devices, and photocatalysis. The majority of the current CDots to date exhibit excitation-wavelength-dependent emissions with their maximum emission limited at the blue-light region. Here, a synthesis of multiple-color-emission CDots by controlled graphitization and surface function is reported. The CDots are synthesized through controlled thermal pyrolysis of citric acid and urea. By regulating the thermal-pyrolysis temperature and ratio of reactants, the maximum emission of the resulting CDots gradually shifts from blue to red light, covering the entire light spectrum. Specifically, the emission position of the CDots can be tuned from 430 to 630 nm through controlling the extent of graphitization and the amount of surface functional groups, COOH. The relative photoluminescence quantum yields of the CDots with blue, green, and red emission reach up to 52.6%, 35.1%, and 12.9%, respectively. Furthermore, it is demonstrated that the CDots can be uniformly dispersed into epoxy resins and be fabricated as transparent CDots/epoxy composites for multiple-color- and white-light-emitting devices. This research opens a door for developing low-cost CDots as alternative phosphors for light-emitting devices.

20.
Nano Lett ; 17(11): 6916-6921, 2017 11 08.
Article in English | MEDLINE | ID: mdl-29019240

ABSTRACT

Structurally controlled nanoparticles, such as core-shell nanocomposite particles by combining two or more compositions, possess enhanced or new functionalities that benefited from the synergistic coupling of the two components. Here we report new nanocomposite particles with self-assembled porphyrin arrays as the core surrounded by amorphous silica as the shell. The synthesis of such nanocomposite nanoparticles was conducted through a combined surfactant micelle confined self-assembly and silicate sol-gel process using optically active porphyrin as a functional building block. Depending on kinetic conditions, these particles exhibit structure and function at multiple length scales and locations. At the molecular scale, the porphyrins as the building blocks provide well-defined macromolecular structures for noncovalent self-assembly and unique chemistry for high-yield generation of singlet oxygen for photodynamic therapy (PDT). On the nanoscale, controlled noncovalent interactions of the porphyrin building block result in an extensive self-assembled porphyrin network that enables efficient energy transfer and impressive fluorescence for cell labeling, evidenced by absorption and photoluminescence spectra. Finally, the thin silicate shell on the nanoparticle surface allows easy functionalization, and the resultant targeting porphyrin-silica nanocomposites can selectively destroy tumor cells upon receiving light irradiation.


Subject(s)
Delayed-Action Preparations/chemistry , Metalloporphyrins/administration & dosage , Nanocomposites/chemistry , Photosensitizing Agents/administration & dosage , Silicon Dioxide/chemistry , Energy Transfer , HeLa Cells , Humans , Hydrogen-Ion Concentration , Metalloporphyrins/chemistry , Metalloporphyrins/pharmacology , Nanocomposites/ultrastructure , Nanoparticles/chemistry , Nanoparticles/ultrastructure , Neoplasms/drug therapy , Photochemotherapy/methods , Photosensitizing Agents/chemistry , Photosensitizing Agents/pharmacology , Singlet Oxygen/chemistry
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