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1.
Phys Chem Chem Phys ; 22(3): 981-984, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31912822

RESUMO

Herein, we propose a new approach of molecule occupancy via a vapor treatment to facilitate the conversion of PbI2 to perovskite in sequential deposition. We have shown that the morphology of PbI2 and the subsequent crystallization of perovskite can be effectively tuned, thus leading to the elimination of residual PbI2 and promotion of perovskite growth.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31880856

RESUMO

Herein, near-infrared (NIR) photocontrolled iodide-mediated reversible-deactivation radical polymerization (RDRP) of methacrylates, without an external photocatalyst, was developed using an alkyl iodide (e.g., 2-iodo-2-methylpropionitrile) as the initiator at room temperature. This example is the first use of a series of special solvents containing carbonyl groups (e.g., 1,3-dimethyl-2-imidazolidinone) as both solvent and catalyst for photocontrolled RDRP using long-wavelength (λmax =730 nm) irradiation. The polymerization system comprises monomer, alkyl iodide initiator, and solvent. Well-defined polymers were synthesized with excellent control over the molecular weights and molecular weight distributions (Mw /Mn <1.21). The living features of this system were confirmed by polymerization kinetics, multiple controlled "on-off" light switching cycles, and chain extension experiments. Importantly, the polymerizations proceeded successfully with various barriers (pork skin and A4 paper), demonstrating the advantage of high-penetration NIR light.

3.
Macromol Rapid Commun ; 40(2): e1800327, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30027663

RESUMO

A series of hydrophilic poly(poly(ethylene glycol) methyl ether methacrylate) (PPEGMA) macroinitiators and stabilizers are synthesized in methanol through in situ photo-controlled bromine-iodine transformation living radical polymerization, where ethyl α-bromophenylacetate (EBPA) is the initial initiator and is converted to an iodo-type initiator in the presence of NaI. The subsequent photo-controlled polymerization-induced self-assembly (photo-PISA) process is achieved by adding a second monomer, hydrophobic benzyl methacrylate (BnMA), under irradiation with blue light emitting diode (LED) light at room temperature. The effect of the target degree of polymerization (DP) of PPEGMA, PBnMA, as well as the solids content on the self-assembly behavior of block copolymer PPEGMA-b-PBnMA is evaluated by gel permeation chromatography (GPC), nuclear magnetic resonance (NMR) spectroscopy, transmission electron microscopy (TEM), and dynamic light scattering (DLS) characterization. Resulting uniform spherical micelles and vesicle aggregates are observed.


Assuntos
Bromo/química , Técnicas de Química Sintética/métodos , Iodo/química , Luz , Polimerização/efeitos da radiação , Ácidos Polimetacrílicos/química , Cromatografia em Gel , Difusão Dinâmica da Luz , Interações Hidrofóbicas e Hidrofílicas , Metacrilatos/química , Metanol/química , Microscopia Eletrônica de Transmissão , Modelos Químicos , Estrutura Molecular , Ácidos Polimetacrílicos/síntese química
4.
Macromol Rapid Commun ; 39(15): e1800151, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29900627

RESUMO

Through the construction of an organic photocatalysis system, photoredox catalyst (PC)/additive, where PC stands for photoredox catalyst, an organocatalyzed step transfer-addition and radical-termination (O-START) polymerization irradiated by blue LED light at room temperature is realized. Different types of α,ω-diiodoperfluoroalkane A and α,ω-unconjugated diene B are copolymerized through O-START efficiently, and generate various kinds of functional semifluorinated polymers, including polyolefins and polyesters. The process is affected by several factors; solvents, additives, and feed ratio of A to B. After optimization of all these components, the polymerization efficiency is greatly improved, generating polymers with both relatively high yield and molecular weight. Considering the mild reaction condition, easy operation process, and free-of-metal-catalyst residues in the polymer product, the organocatalytic polymerization strategy provides a simple and efficient approach to functional semifluorinated polymer materials and hopefully opens up their application in high-tech fields.


Assuntos
Boratos/química , Amarelo de Eosina-(YS)/química , Hidrocarbonetos Fluorados/síntese química , Luz , Polímeros/química , Piranos/química , Catálise , Halogenação , Hidrocarbonetos Fluorados/química , Processos Fotoquímicos , Polimerização , Temperatura Ambiente
5.
Nanoscale ; 10(21): 10277-10287, 2018 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-29790554

RESUMO

The performance of functional polymer nanomaterials is a vigorously discussed topic in polymer science. We devoted ourselves to investigating polymer nanomaterials based on near-infrared (NIR) fluorescence imaging and polymer prodrug in this study. Aza-boron dipyrromethene (BODIPY) is an important organic dye, having characteristics such as environmental resistance, light resistance, high molar extinction coefficient, and fluorescence quantum yield. We incorporated it into our target monomer, which can be polymerized without changing its parent structure in a polar solvent and copolymerized with water-soluble monomer to improve the solubility of the dye in an aqueous solution. At the same time, the hydrophobic drug camptothecin (CPT) was designed as a prodrug monomer, and the polymeric nanoparticles (NPs) with NIR fluorescence imaging and prodrug were synthesized in situ in reversible addition-fragmentation chain transfer (RAFT)-mediated aqueous dispersion polymerization. The dynamic light scattering (DLS) and transmission electron microscopy (TEM) revealed the final uniform size of the dual-functional polymeric NPs morphology. The dual-functional polymeric NPs had a strong absorption and emission signal in the NIR region (>650 nm) based on the fluorescence tests. In consideration of the long-term biological toxicity, confocal laser scanning microscopy (CLSM) results indicated that the dual-functional NPs with controlled drug content exhibited effective capability of killing HeLa cells. In addition, in vivo imaging of the dual-functional NPs was observed in real time, and the fluorescent signals clearly demonstrated the dynamic process of prodrug transfer.

6.
Pharm Biol ; 56(1): 209-216, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29540097

RESUMO

CONTEXT: Rheumatoid arthritis (RA) is a common systemic auto-immune disease, which is characterized by chronic and symmetry synovial inflammation. Crocin has been reported to exhibit anti-inflammatory effects in animal models. OBJECTIVE: This study investigates the anti-inflammatory and anti-arthritic effects of crocin on type II collagen-induced arthritis (CIA) in Wistar rats. MATERIALS AND METHODS: The CIA rat model was established and randomly divided into five groups with or without crocin treatment (10, 20 or 40 mg/kg), which was started on day 21 after arthritis induction and persisted for 36 days. The symptoms and molecular mechanisms of CIA and crocin-treated CIA rats were compared and investigated. RESULTS: CIA rats presented severe RA symptoms, including high arthritis score, paw swelling, joint inflammation, bone erosion, chondrocyte death, cartilage destruction, enhanced expressions of matrix metalloproteinase (MMP) and pro-inflammatory cytokines. However, crocin could mitigate these symptoms. Crocin (40 mg/kg) exhibited the most efficient therapeutic function on CIA rats: the histological scores of joint inflammation, bone erosion, chondrocyte death, cartilage surface erosion, and bone erosion of CIA rats receiving 40 mg/kg crocin treatment were comparable to the normal rats. MMP-1, -3 and -13 protein expression levels of CIA rats with 40 mg/kg crocin treatment were decreased to levels similar to normal rats. Moreover, crocin could also inhibit the expression of TNF-α, IL-17, IL-6 and CXCL8 in serum and ankle tissues of CIA rats. CONCLUSIONS: In summary, crocin exhibits therapeutic potential for RA, by mitigating the symptoms and inhibiting the pro-inflammatory factor expression.


Assuntos
Anti-Inflamatórios/farmacologia , Artrite Experimental/tratamento farmacológico , Carotenoides/farmacologia , Colágeno Tipo II , Articulações/efeitos dos fármacos , Animais , Artrite Experimental/sangue , Artrite Experimental/induzido quimicamente , Artrite Experimental/patologia , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Condrócitos/patologia , Citocinas/sangue , Citocinas/genética , Relação Dose-Resposta a Droga , Mediadores da Inflamação/sangue , Articulações/metabolismo , Articulações/patologia , Metaloproteinases da Matriz/sangue , Ratos Wistar , Fatores de Tempo
7.
Cell Prolif ; 51(1)2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29194827

RESUMO

OBJECTIVES: Long non-coding RNA cancer susceptibility candidate 2 (CASC2) is a novel lncRNA and has been indicated as playing tumour suppressor gene in several tumours. However, the role of CASC2 in osteosarcoma is still uncovered. MATERIALS AND METHODS: The CASC2 and miR-181a expressions were measured via qRT-PCR. CCK-8 assay and colony formation assay were performed to determine the cell growth, and transwell assay was performed to assess the cell invasion. RESULTS: We showed that CASC2 expression was downregulated in osteosarcoma samples and cell lines. Moreover, we showed that downregulated expression of CASC2 was correlated with advanced TNM stage. Furthermore, overexpression of CASC2 inhibited osteosarcoma cell proliferation, colony formation, and invasion. In addition, we indicated that ectopic expression of CASC2 suppressed miR-181a expression and enhanced the expression of Ras association domain family member 6 (RASSF6), PTEN and ATM in osteosarcoma cell, which were the direct target gene of miR-181a. Moreover, we indicated that RASSF6 expression was downregulated in osteosarcoma samples and cell lines and downregulated expression of RASSF6 was correlated with advanced TNM stage. We found that the expression of RASSF6 was positively correlated with the expression of CASC2 in osteosarcoma tissues. Ectopic expression of CASC2 suppressed the osteosarcoma cell proliferation, colony formation and invasion through regulating RASSF6 expression. CONCLUSIONS: Our data illuminated that CASC2 acted as a tumour suppressor in osteosarcoma progression.


Assuntos
Neoplasias Ósseas/genética , Regulação Neoplásica da Expressão Gênica/genética , MicroRNAs/genética , Osteossarcoma/genética , RNA Longo não Codificante/genética , Proteínas Supressoras de Tumor/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação para Baixo , Humanos , Proteínas Monoméricas de Ligação ao GTP/genética
8.
Macromol Rapid Commun ; 38(12)2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28422360

RESUMO

Iron-mediated atom transfer radical polymerization (ATRP) has gained extensive attention because of the superiority of iron catalysts, such as low toxicity, abundant reserves, and good biocompatibility. Herein, a practical iron catalyst recycling system, photoinduced iron-based water-induced phase separable catalysis ATRP with initiators for continuous activator regeneration, at room temperature is developed for the first time. In this polymerization system, the polymerization is conducted in homogenous solvents consisting of p-xylene and ethanol, using commercially available 5,10,15,20-tetraphenyl-21H,23H-porphine iron(III) chloride as the iron catalyst, ethyl 2-bromophenylacetate as the ATRP initiator, 2,4,6-trimethylbenzoyl diphenylphosphine oxide as the photoinitiator, and poly(ethylene glycol) methyl ether methacrylate as the model hydrophilic monomer. After polymerization, a certain amount of water is added to induce the phase separation so that the catalyst can be separated and recycled in p-xylene phase with very low residual metal complexes (<12 ppm) in the resultant polymers even after six times recycle experiments.


Assuntos
Ferro/química , Luz , Metacrilatos/química , Éteres Metílicos/química , Água/química , Catálise , Complexo Ferro-Dextran/química
9.
Macromol Rapid Commun ; 38(13)2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27862536

RESUMO

A new polymerization method, termed as step transfer-addition and radical-termination, is developed for the step-growth radical polymerization of α,ω-unconjugated dienes under irradiation of visible light at room temperature (25 °C) for the first time. α,ω-Diiodoperfluoroalkane monomers (signified as A) are added onto α,ω-unconjugated dienes (signified as B) alternatively and efficiently with the generation of perfluorocarbon-containing alternating copolymers (AB)n . Based on the combined analyses of polymerization kinetics and NMR spectra (1 H and 19 F), the mechanism of the novel polymerization method, including the side reaction, is proposed. This novel polymerization method provides a new strategy not only for the step-growth radical polymerization of α,ω-unconjugated dienes but also for the construction of high molecular weight perfluorocarbon-containing alternating copolymers.


Assuntos
Fotoquímica/métodos , Polimerização , Polímeros/síntese química , Cinética , Luz
10.
Macromol Rapid Commun ; 38(10)2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27792297

RESUMO

It is well known that the recently developed photoinduced metal-free atom transfer radical polymerization (ATRP) has been considered as a promising methodology to completely eliminate transition metal residue in polymers. However, a serious problem needs to be improved, namely, large amount of organic photocatalysts should be used to keep the controllability over molecular weights and molecular weight distributions. In this work, a novel photocatalyst 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN) with strong excited state reduction potential is successfully used to mediate a metal-free ATRP of methyl methacrylate just with parts per million (ppm) level usage under irradiation of blue light emitting diode at room temperature, using ethyl α-bromophenyl-acetate as a typical initiator with high initiator efficiency. The polymerization kinetic study, multiple controlled "on-off" light switching cycle regulation, and chain extension experiment confirm the "living"/controlled features of this promising photoinduced metal-free ATRP system with good molecular weight control in the presence of ppm level photocatalyst 4CzIPN.


Assuntos
Carbazóis/química , Técnicas de Química Analítica/métodos , Metilmetacrilato/química , Nitrilos/química , Processos Fotoquímicos , Polimerização , Catálise
11.
Nanoscale ; 8(33): 15323-39, 2016 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-27503666

RESUMO

The multifunctional nano-micelle platform holds great promise to enhance the accuracy and efficiency of cancer diagnosis and therapy. In this work, an amphiphilic poly[(poly(ethylene glycol) methyl ether methacrylate)-co-(3-aminopropyl methacrylate)]-block-poly(methyl methacrylate) (P(PEGMA-co-APMA)-b-PMMA) block copolymer was synthesized by successive RAFT polymerizations and subsequent chemical modification. Then the multifunctional micelles with high solubility in physiological environments were developed by a self-assembly and crosslinking processes. The photosensitizer segment, 5,10,15,20-tetrakis (4-carboxyphenyl) porphyrin (TCPP), serves as a tetra-functional cross-linker, photodynamic agent, fluorescence indicator, as well as magnetic resonance (MR) contrast agent after labelling with manganese ions (Mn(2+)), while IR825 simultaneously locating in the interior of the fabricated micelles contributed to the photoacoustic (PA) imaging ability and the photothermal effect. The prepared nanoparticles show great stability in a physiological environment with uniform morphology and diameters of around 80 nm as disclosed by stability investigation, TEM and DLS analysis. IR825@P(PEGMA-co-APMA)-b-PMMA@TCPP/Mn nanoparticles displayed high in vivo tumor uptake with a long blood circulation half-life (∼3.64 h) by the EPR effect after intravenous (i.v.) injection, as revealed by fluorescence, MR and PA imaging models. In vivo anti-tumor effects were achieved via a combined photothermal and photodynamic therapy without noticeable dark toxicity, and this strategy was able to induce a remarkably improved synergistic therapeutic effect to both superficial and deep regions of tumors under mild conditions compared with either single photothermal or photodynamic mechanisms.

12.
Chem Commun (Camb) ; 52(72): 10850-3, 2016 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-27439380

RESUMO

A simple and highly efficient visible-light induced iodine-mediated living radical polymerization system for functional monomers (DMAEMA, PEGMA and GMA) was successfully developed in bulk without the addition of any catalysts for the first time. In addition, sunlight was also applicable for the construction of this photoinduced bulk living radical polymerization.

13.
Macromol Rapid Commun ; 37(16): 1337-43, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27296245

RESUMO

Photoinduced initiators for continuous activator regeneration atom transfer radical polymerization (ATRP) of hydrophilic monomers in heptane/ethanol latent-biphasic system for copper catalyst separation and recycling have been realized for the first time at room temperature with different wavelengths of visible light LED (green, blue, purple, and white LED) as external stimulus, using 2-bromophenylacetate as the ATRP initiator and camphorquinone/triethylamine as the photoinitiator. In this system, hybrid catalyst complex (HCc) is synthesized as a novel nonpolar catalyst, which is preferentially dissolved in heptane. The hydrophilic polymers obtained catalyzed by HCc in heptane/ethanol mixture solvent show typical "living" features, for example, the values of Mn,GPC increase linearly with monomer conversion up to quantitative level (>96%) and the molecular weight distributions were kept narrow (Mw /Mn < 1.20) throughout the polymerization process. It should be noted that the excellent controllability of this novel polymerization system can be achieved even after 5 catalyst recycling experiments under LED irradiation.


Assuntos
Acetatos/química , Cânfora/análogos & derivados , Etilaminas/química , Fenóis/química , Polímeros/síntese química , Cânfora/química , Catálise , Cobre/química , Etanol/química , Heptanos/química , Luz , Peso Molecular , Processos Fotoquímicos , Polimerização , Polímeros/efeitos da radiação , Solventes/química , Temperatura Ambiente
14.
Biomaterials ; 98: 23-30, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27177219

RESUMO

Real-time in vivo pH imaging in the tumor, as well as designing therapies responsive to the acidic tumor microenvironment to achieve optimized therapeutic outcomes have been of great interests in the field of nanomedicine. Herein, a pH-responsive near-infrared (NIR) croconine (Croc) dye is able to induce the self-assembly of human serum albumin (HSA) to form HSA-Croc nanoparticles useful not only for real-time ratiometric photoacoustic pH imaging of the tumor, but also for pH responsive photothermal therapy with unexpected great performance against tumors with relatively large sizes. Such HSA-Croc nanoparticles upon intravenous injection exhibit efficient tumor homing. As the decrease of pH, the absorption of Croc at 810 nm would increase while that at 680 nm would decrease, allowing real-time pH sensing in the tumor by double-wavelength ratiometric photoacoustic imaging, which reveals the largely decreased pH inside the cores of large tumors. Moreover, utilizing HSA-Croc as a pH-responsive photothermal agent, effective photothermal ablation of large tumors is realized, likely owing to the more evenly distributed intratumoral heating compared to that achieved by conventional pH-insensitive photothermal agents, which are effective mostly for tumors with small sizes.


Assuntos
Corantes/química , Hipertermia Induzida , Nanopartículas/química , Neoplasias/terapia , Técnicas Fotoacústicas/métodos , Fototerapia , Albumina Sérica/química , Animais , Feminino , Humanos , Concentração de Íons de Hidrogênio , Raios Infravermelhos , Camundongos Nus , Nanopartículas/ultraestrutura , Neoplasias/patologia
15.
Polymers (Basel) ; 9(1)2016 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-30970681

RESUMO

Compared to unhealthy UV or γ-ray and high-energy-consumption thermal external stimuli, the promising light emitting diode (LED) external stimulus has some outstanding technological merits such as narrow wavelength distribution, low heat generation and energy consumption, and safety for human beings. In this work, a novel reversible addition-fragmentation transfer (RAFT) polymerization system for acrylonitrile (AN) was developed under the irradiation of blue LED light at room temperature, using 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN) as a novel radical initiator and 2-cyanoprop-2-yl-1-dithionaphthalate (CPDN) as the typical chain transfer agent. Well-defined polyacrylonitrile (PAN) with a controlled molecular weight and narrow molecular weight distribution was successfully synthesized. This strategy may provide another effective method for scientific researchers or the industrial community to synthesize a PAN-based precursor of carbon fibers.

16.
Polymers (Basel) ; 8(2)2016 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-30979123

RESUMO

Atom Transfer Radical Polymerization (ATRP) is an important polymerization process in polymer synthesis. However, a typical ATRP system has some drawbacks. For example, it needs a large amount of transition metal catalyst, and it is difficult or expensive to remove the metal catalyst residue in products. In order to reduce the amount of catalyst and considering good biocompatibility and low toxicity of the iron catalyst, in this work, we developed a homogeneous polymerization system of initiators for continuous activator regeneration ATRP (ICAR ATRP) with just a ppm level of iron catalyst. Herein, we used oil-soluble iron (III) acetylacetonate (Fe(acac)3) as the organometallic catalyst, 1,1'-azobis (cyclohexanecarbonitrile) (ACHN) with longer half-life period as the thermal initiator, ethyl 2-bromophenylacetate (EBPA) as the initiator, triphenylphosphine (PPh3) as the ligand, toluene as the solvent and methyl methacrylate (MMA) as the model monomer. The factors related with the polymerization system, such as concentration of Fe(acac)3 and ACHN and polymerization kinetics, were investigated in detail at 90 °C. It was found that a polymer with an acceptable molecular weight distribution (Mw/Mn = 1.43 at 45.9% of monomer conversion) could be obtained even with 1 ppm of Fe(acac)3, making it needless to remove the residual metal in the resultant polymers, which makes such an ICAR ATRP process much more industrially attractive. The "living" features of this polymerization system were further confirmed by chain-extension experiment.

17.
Polymers (Basel) ; 8(3)2016 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-30979165

RESUMO

It is well known that well-defined polyacrylonitrile (PAN) with high molecular weight (Mw > 106 g·mol-1) is an excellent precursor for high performance carbon fiber. In this work, a strategy for initiators for a continuous activator regeneration atom transfer radical polymerization (ICAR ATRP) system for acrylonitrile (AN) was firstly established by using CuCl2·2H2O as the catalyst and 2,2'-azobis(2-methylpropionitrile) (AIBN) as the thermal initiator in the presence of ppm level catalyst under ambient and high pressure (5 kbar). The effect of catalyst concentration and polymerization temperature on the polymerization behaviors was investigated. It is important that PAN with ultrahigh viscosity and average molecular weight (Mη = 1,034,500 g·mol-1) could be synthesized within 2 h under high pressure.

18.
Macromol Rapid Commun ; 37(2): 143-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26506506

RESUMO

How to simply and efficiently separate and recycle catalyst has still been a constraint for the wide application of atom transfer radical polymerization (ATRP), especially for the polymerization systems with hydrophilic monomers because the polar functional groups may coordinate with transition metal salts, resulting in abundant catalyst residual in the resultant water-soluble polymers. In order to overcome this problem, a latent-biphasic system is developed, which can be successfully used for ATRP catalyst separation and recycling in situ for various kinds of hydrophilic monomers for the first time, such as poly(ethylene glycol) monomethyl ether methacrylate (PEGMA), 2-hydroxyethyl methacrylate (HEMA), 2-(dimethylamino)ethyl methacrylate (DMAEMA), N,N-dimethyl acrylamide (DMA), and N-isopropylacrylamide (NIPAM). Herein, random copolymer of octadecyl acrylate (OA), MA-Ln (2-(bis(pyridin-2-ylmethyl)amino)ethyl acrylate), and POA-ran-P(MA-Ln) is designed as the macroligand, and heptane/ethanol is selected as the biphasic solvent. Copper(II) bromide (CuBr2 ) is employed as the catalyst, PEG-bound 2-bromo-2-methylpropanoate (PEG350 -Br) as the water-soluble ATRP initiator and 2,2'-azobis(isobutyronitrile) (AIBN) as the azo-initiator to establish an ICAR (initiators for continuous activator regeneration) ATRP system. Importantly, well-defined water-soluble polymers are obtained even though the recyclable catalyst is used for sixth times.


Assuntos
Metacrilatos/química , Polietilenoglicóis/química , Água/química , Acrilatos/química , Brometos/química , Catálise , Cobre/química , Reutilização de Equipamento , Etanol , Radicais Livres/química , Heptanos , Interações Hidrofóbicas e Hidrofílicas , Cinética , Nitrilos/química , Polimerização , Soluções , Solventes , Temperatura Ambiente
19.
Adv Mater ; 27(43): 6820-7, 2015 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-26418312

RESUMO

A photoacoustic nanoprobe is self-assembled from human serum albumin and two types of dye molecules, one is inert to pH and the other is pH sensitive. This probe and the quantitative ratiometric photoacoustic pH imaging method are shown to have high safety, be easy-to-operate, and have depth-independent accuracy for real-time in vivo pH imaging of entire tumors. These features make them promising for future cancer prognosis and therapeutic planning.


Assuntos
Corantes Fluorescentes/química , Nanoestruturas/química , Imagem Óptica/métodos , Técnicas Fotoacústicas/métodos , Albumina Sérica/química , Benzoatos/química , Linhagem Celular Tumoral , Humanos , Concentração de Íons de Hidrogênio , Indóis/química , Modelos Moleculares , Oxazinas/química , Conformação Proteica
20.
Nanoscale ; 7(39): 16399-416, 2015 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-26394168

RESUMO

Responsive block copolymer micelles emerging as promising imaging and drug delivery systems show high stability and on-demand drug release activities. Herein, we developed self-assembled pH-responsive NIR emission micelles entrapped with doxorubicin (DOX) within the cores by the electrostatic interactions for fluorescence imaging and chemotherapy applications. The block copolymer, poly(methacrylic acid)-block-poly[(poly(ethylene glycol) methyl ether methacrylate)-co-boron dipyrromethene derivatives] (PMAA-b-P(PEGMA-co-BODIPY), was synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization, and the molecular weight distribution of this copolymer was narrow (Mw/Mn = 1.31). The NIR fluorescence enhancement induced by the phenol/phenolate interconversion equilibrium works as a switch in response to the intracellular pH fluctuations. DOX-loaded PMAA-b-P(PEGMA-co-BODIPY) micelles can detect the physiological pH fluctuations with a pKa near physiological conditions (∼7.52), and showed pH-responsive collapse and an obvious acid promoted anticancer drug release behavior (over 58.8-62.8% in 10 h). Real-time imaging of intracellular pH variations was performed and a significant chemotherapy effect was demonstrated against HeLa cells.


Assuntos
Compostos de Boro , Doxorrubicina , Micelas , Imagem Óptica , Compostos de Boro/química , Compostos de Boro/farmacocinética , Compostos de Boro/farmacologia , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Metacrilatos/química , Metacrilatos/farmacocinética , Metacrilatos/farmacologia , Polietilenoglicóis/química , Polietilenoglicóis/farmacocinética , Polietilenoglicóis/farmacologia , Ácidos Polimetacrílicos/química , Ácidos Polimetacrílicos/farmacocinética , Ácidos Polimetacrílicos/farmacologia
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