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1.
Cell Prolif ; 53(4): e12786, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32301195

RESUMO

OBJECTIVES: Photodynamic therapy (PDT) is a novel non-invasive therapeutic method, which has been widely applied for the treatment of human oral cancers. However, the problems of undesirable singlet oxygen (1 O2 ) quantum yields and long-term phototoxicity were inevitable during the application of traditional photosensitizers. Therefore, it is necessary to explore novel photosensitizers for the improvement of therapeutic effects. In our study, the sulphur-doped carbon dots (S-CDs) of high yield of singlet oxygen (1 O2 ) were synthesized as a nano-photosensitizer for OSCC to improve the PDT efficacy in clinical practice. MATERIALS AND METHODS: After synthesis of the novel S-CDs, the size, morphologic characteristics, surface potential and yield of singlet oxygen (1 O2 ) were determined. In vitro study was performed to compare the therapeutic effect as well as the biocompatibility of the novel S-CDs to those of 5-ALA. Besides, possible mechanism of action was illustrated. RESULTS: After synthesis of the novel S-CDs, the size, morphologic characteristics, surface potential and yield of singlet oxygen (1 O2 ) were determined. In vitro study was performed to compare the therapeutic effect as well as the biocompatibility of the novel S-CDs to those of 5-ALA. Besides, possible mechanism of action was illustrated. CONCLUSIONS: These data from the in vitro study demonstrated the promising safety profile of the low dose (nmol/L) S-CDs, which indicated the novel S-CDs could be used as a promising photodynamic agent for oral cancer therapy.


Assuntos
Carbono/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias Bucais/tratamento farmacológico , Fármacos Fotossensibilizantes/farmacologia , Enxofre/farmacologia , Apoptose/efeitos dos fármacos , Carbono/química , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Humanos , Modelos Moleculares , Neoplasias Bucais/patologia , Nanopartículas/química , Nanopartículas/ultraestrutura , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Enxofre/química
2.
Anal Bioanal Chem ; 412(4): 871-880, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31901958

RESUMO

Novel carbon dots (CDs) were synthesized by a one-pot hydrothermal approach using ampicillin as a precursor, and the as-prepared CDs exhibited a high quantum yield (23%). The CDs were found to possess abundant surface functional groups, thus providing good permeability to the cell, and the antibacterial activity of CDs was evaluated. S. aureus and L. monocytogenes were selected as model bacteria, and our results showed that the CDs exhibited antibacterial activity against S. aureus and L. monocytogenes under visible light illumination, even at low concentrations. The antibacterial mechanism is believed to be the production of reactive oxygen species (ROS) from CDs under visible light irradiation, which attacked the bacterial cell membranes, resulting in the death of the bacteria. In addition, because of the multicolor fluorescence properties of CDs, staining of S. aureus and L. monocytogenes obtained multicolor fluorescence images at different excitation wavelengths. Based on these results, CDs are a promising candidate material for biological applications. Graphical abstract.


Assuntos
Ampicilina/farmacologia , Antibacterianos/farmacologia , Carbono/farmacologia , Listeria monocytogenes/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Ampicilina/análogos & derivados , Ampicilina/síntese química , Antibacterianos/síntese química , Antibacterianos/química , Carbono/química , Humanos , Listeriose/tratamento farmacológico , Nanopartículas/química , Infecções Estafilocócicas/tratamento farmacológico
3.
Chem Commun (Camb) ; 56(15): 2316-2319, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31990011

RESUMO

Carbon quantum dots derived from gentamicin sulfate are directly developed by facile calcination at different temperatures. A promising nanomaterial, CQD180, even shows a much superior antibacterial activity compared with the antibiotic counterpart and low drug resistance, by preserving the active structure of the starting materials and providing an additional antibacterial mode arising from the positive charge surface and induced reactive oxygen species simultaneously. Moreover, CQD180 can effectively disrupt mature Staphylococcus aureus biofilm and selectively eliminate bacteria over mammalian cells.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Carbono/farmacologia , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Gentamicinas/farmacologia , Pontos Quânticos/química , Staphylococcus aureus/efeitos dos fármacos , Células 3T3 , Animais , Antibacterianos/química , Carbono/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Gentamicinas/química , Células HEK293 , Humanos , Camundongos , Testes de Sensibilidade Microbiana
4.
Cell Prolif ; 53(1): e12713, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31691382

RESUMO

OBJECTIVES: Carbon dots (CDs), as a fascinating class of fluorescent carbon nanomaterials, have been proven to be powerful tools in the field of bioimaging and biosensing due to their small size, suitable photostability and favourable biocompatibility. However, the cellular uptake of free CDs lacks selectivity and the same negative charges as cell membranes may cause inefficient cell internalization. In this study, an efficient detecting and targeting nanosystem was developed based on the DNA aptamer AS1411 modified CDs with polyethyleneimine (PEI) as connecting bridge. MATERIALS AND METHODS: Hydrothermally prepared CDs were assembled with positive-charged PEI, followed by conjugation with AS1411 through electrostatic interaction to form CDs-PEI-AS1411 nanocomplexes. The CDs, CDs-PEI and CDs-PEI-AS1411 were characterized by transmission electron microscopy (TEM), fourier transform infrared (FTIR) spectra, UV-vis spectra, zeta potential measurements and capillary electrophoresis characterizations. The cytotoxicity investigation of the CDs-PEI-AS1411 and CDs-PEI in both MCF-7 and L929 cells was carried out by the CCK-8 assay. The cellular uptake of the CDs-PEI-AS1411 was studied with confocal microscopy and flow cytometry. RESULTS: The as-prepared nanosystem possessed good photostability and no obvious cytotoxicity. On the basis of the confocal laser scanning microscope observation and the flow cytometry studies, the cellular uptake of CDs-PEI-AS1411 nanosystem in MCF-7 cells was significantly higher than that of L929 cells, which revealed the highly selective detection ability of nucleolin-positive cells. CONCLUSIONS: The results of this study indicated that the CDs-PEI-AS1411 nanosystem had a potential value in cancer cell targeted imaging.


Assuntos
Aptâmeros de Nucleotídeos , Sistemas de Liberação de Medicamentos , Citometria de Fluxo , Neoplasias , Oligodesoxirribonucleotídeos , Pontos Quânticos/química , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/farmacocinética , Aptâmeros de Nucleotídeos/farmacologia , Carbono/química , Carbono/farmacocinética , Carbono/farmacologia , Humanos , Células MCF-7 , Microscopia Confocal , Neoplasias/diagnóstico por imagem , Neoplasias/metabolismo , Oligodesoxirribonucleotídeos/química , Oligodesoxirribonucleotídeos/farmacocinética , Oligodesoxirribonucleotídeos/farmacologia , Polietilenoimina/química , Polietilenoimina/farmacocinética , Polietilenoimina/farmacologia
5.
J Agric Food Chem ; 67(45): 12558-12564, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31609622

RESUMO

All four stereoisomers of naturally occurring 6-(2-hydroxy-6-phenylhex-1-yl)-5,6-dihydro-2H-pyran-2-one (1) were synthesized by employing yeast-reduction products with high optical purity [from 95% enantiomeric excess (ee) to more than 99% ee], and then their phytotoxicities against lettuce and Italian ryegrass were evaluated. In the Italian ryegrass seedlings test, (6S,2'R)-1 showed the most potent and stereospecific activity against the shoots (IC50 = 260 µM) and roots (IC50 = 43.2 µM), with a significant difference from other stereoisomers. The highest seed germination inhibitory activity against Italian ryegrass seed was also observed in (6S,2'R)-1, showing a 53% germination ratio from the control at 1000 µM. This advantageous (6S,2'R) stereochemistry was employed in the syntheses of α,ß-dihydro, 2'-dehydroxy, and 2'-methoxy derivatives 13-15. By the test using these derivatives, the importance of the α,ß-unsaturated double bond and hydroxy group bonding to a chiral center on the 6-alkyl chain of 5,6-dihydro-α-pyrone for phytotoxicity was determined. In the test against lettuce, the 6S configuration and (6S,2'S) configuration were necessary for growth inhibition (IC50 = ca. 60 µM) and germination inhibition (63% germination ratio at 1000 µM), respectively.


Assuntos
Carbono/química , Herbicidas/farmacologia , Piranos/química , Carbono/farmacologia , Germinação/efeitos dos fármacos , Herbicidas/síntese química , Herbicidas/química , Alface/efeitos dos fármacos , Alface/crescimento & desenvolvimento , Lolium/efeitos dos fármacos , Lolium/crescimento & desenvolvimento , Estrutura Molecular , Piranos/farmacologia , Estereoisomerismo , Relação Estrutura-Atividade
6.
Inorg Chem ; 58(19): 13394-13402, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31556604

RESUMO

Carbon dots (CDs), as an effective bioimaging agent, have aroused widespread interest. With the increasing number of CDs used in photodynamic therapy (PDT), developing efficient CDs with multiple functions such as imaging and phototherapy has become a new challenge. Herein, a new type of copper-doped CDs (Cu-CDs) with a high fluorescence quantum yield of 24.4% was synthesized from a copper complex of poly(acrylic acid) through coordination between the carboxyl group and copper ions. Owing to their good solubility, bright fluorescence, and low cytotoxicity, the Cu-CDs can be used for fluorescence imaging in both the HeLa (human cervical cancer) cell line and SH-SY5Y (human neuroblastoma cells) multicellular spheroids (3D MCs). More importantly, the Cu-CDs show a high quantum yield of singlet oxygen (1O2; 36%), good photoinduced cytotoxicity, and effective inhibition of 3D MC growth. Therefore, the Cu-CDs can be used as a promising imaging-guided PDT agent. This study provides a new carbon-based nanomaterial for multifunctional photodiagnostic and therapeutic agents for biological applications.


Assuntos
Carbono/farmacologia , Cobre/farmacologia , Corantes Fluorescentes/farmacologia , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Carbono/química , Linhagem Celular Tumoral , Cobre/química , Corantes Fluorescentes/química , Células HeLa , Humanos , Nanopartículas/química , Imagem Óptica , Fotoquimioterapia
7.
Molecules ; 24(18)2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31500170

RESUMO

New, improved therapies to reduce blood glucose are required for treating diabetes mellitus (DM). Here, we investigated the use of a new nanomaterial candidate for DM treatment, carbon nanoparticles (CNPs). CNPs were prepared by carbonization using a polysaccharide from Arctium lappa L. root as the carbon source. The chemical structure and morphology of the CNPs were characterized using Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, elemental analysis, and transmission electron microscopy. CNPs were spherical, 10-20 nm in size, consisting of C, H, O, and N, and featuring various functional groups, including C=O, C=C, C-O, and C-N. In vitro, the as-prepared CNPs could inhibit α-glucosidase with an IC50 value of 0.5677 mg/mL, which is close to that of the reference drug acarbose. Moreover, in vivo hypoglycemic assays revealed that the CNPs significantly reduced fasting blood-glucose levels in mice with diabetes induced by high-fat diet and streptozocin, lowering blood glucose after intragastric administration for 42 days. To the best of our knowledge, this is the first report of CNPs exhibiting α-glucosidase inhibition and a hypoglycemic effect in diabetic mice. These findings suggest the therapeutic potential of CNPs for diabetes.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Inibidores de Glicosídeo Hidrolases/farmacologia , Hipoglicemia/tratamento farmacológico , alfa-Glucosidases/genética , Animais , Glicemia/efeitos dos fármacos , Metabolismo dos Carboidratos/efeitos dos fármacos , Carbono/química , Carbono/farmacologia , Diabetes Mellitus Experimental/patologia , Modelos Animais de Doenças , Inibidores de Glicosídeo Hidrolases/química , Humanos , Hipoglicemia/patologia , Camundongos , Camundongos Endogâmicos NOD , Nanopartículas/química , Espectroscopia de Infravermelho com Transformada de Fourier , alfa-Glucosidases/química
8.
ACS Appl Mater Interfaces ; 11(36): 32798-32807, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31430113

RESUMO

Graphdiyne has attracted much interest from researchers for their potential applications in energy storage, catalysis, and biomedical areas. As one of the derivatives of graphdiyne, graphdiyne quantum dots (GDQDs) may possess superior bioactivity due to active acetylene units. However, the biological application of biocompatible GDQDs have not been reported so far. Herein, GDQDs with uniform size and good crystallization were prepared via a classical solvothermal method. The GDQDs exhibit excitation- and pH-dependent fluorescence emission as well as superior photostability, demonstrating their potential for bioimaging. The GDQDs demonstrate efficient cellular uptake and cell imaging without induction of detectable cytotoxic effects in vitro. Systematical safety evaluation further confirmed good biocompatibility of the GDQDs in vivo. Our study preliminarily validates the application of the GDQDs in biomedicine and encourages more thorough studies for better realizing the potential of GDQDs.


Assuntos
Materiais Biocompatíveis/farmacologia , Carbono/farmacologia , Pontos Quânticos/química , Animais , Carbono/química , Linhagem Celular Tumoral , Eritrócitos/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Imageamento Tridimensional , Camundongos Endogâmicos BALB C , Fenômenos Ópticos , Pontos Quânticos/ultraestrutura
9.
Nanoscale ; 11(35): 16351-16361, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31432837

RESUMO

Carbon-based light-activated materials can absorb optical energy to generate photoacoustic (PA) signals for imaging or transduce optical photons to thermal energy, which holds great promise for biomedical applications. Herein, we synthesize hollow and mesoporous carbon nanospheres (HMCNs) with uniform size on a large scale. The properties of hollow cavity and mesoporous structures make the HMCNs achieve high drug loading (480 mg DOX per g HMCNs). The present intense near infrared (NIR) absorbance achieves excellent photoacoustic imaging ability and photothermal conversion efficacy (32.0%). More interestingly, the encapsulated drugs can have a triggered release under NIR irradiation. The investigations in vitro and in vivo demonstrate that HMCNs have excellent biocompatibility, and accumulate in tumors by the enhanced permeability and retention (EPR) effect. Moreover, under NIR irradiation, in vivo evaluation shows that HMCNs can perform strong PA imaging, and induce great tumor inhibition by the combination of chemotherapy and PTT under the guidance of photoacoustic imaging. The present study provides new insight for design of novel biocompatible light-activated carbons for cancer nanotheranostics.


Assuntos
Carbono , Doxiciclina , Hipertermia Induzida , Nanosferas , Neoplasias Experimentais , Técnicas Fotoacústicas , Animais , Carbono/química , Carbono/farmacologia , Linhagem Celular Tumoral , Doxiciclina/química , Doxiciclina/farmacocinética , Doxiciclina/farmacologia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanosferas/química , Nanosferas/uso terapêutico , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/terapia , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Int J Biol Macromol ; 138: 29-36, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31302123

RESUMO

In this study, we employed multiple spectroscopic methods to analyze the effects of carbon nanoparticles (CNPs) on structure of cytochrome c (Cyt c) and mitochondrial function in plant cells. The tertiary structures of aromatic amino acid in Cyt c were not changed after addition of CNPs. Cyt c was found to be absorbed on the surfaces of CNPs in a non-linear manner and only bound Cyt c can be reduced. In addition, the binding of Cyt c was found to increase the diameter of CNPs at lower concentrations. The redox potential of Cyt c was almost not affected after treatment with CNPs. There were no obvious differences in cellular ATP after exposure to CNPs, and the mitochondrial membrane potential (MMP) was significantly decreased once the CNPs concentration exceeded 31.25 µg/mL. The levels of reactive oxygen species (ROS) also were increased in BY-2 cells. Taken together, these findings provide basis for the interactions between CNPs and Cyt c, as well as the effect of CNPs treatment on the mitochondria function in plant cells.


Assuntos
Carbono/química , Carbono/farmacologia , Citocromos c/química , Citocromos c/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Nanopartículas , Trifosfato de Adenosina/metabolismo , Carbono/metabolismo , Linhagem Celular , Eletroquímica , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Ligação Proteica , Espécies Reativas de Oxigênio/metabolismo , Análise Espectral
11.
Nanoscale ; 11(27): 12973-12982, 2019 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-31263818

RESUMO

Nano-theranostic agents play important roles in the development of therapeutic methods for serious diseases. In this study, novel carbon dots (CDs) L-CD/C-CD were prepared from Gd(iii) salt/complexes, cationic polymers and citric acid in the hope that they would combine the abilities of gene delivery and multi-modal (MR/FL) imaging. The CDs inherited the properties of good water-solubility and positive charge from their precursor polymers. In vitro gene transfection results showed that the CDs have good transfection efficiency and anti-serum ability, especially for L-CD, which has 74 times higher transfection efficiency than PEI 25 kDa in the presence of 10% serum. The CDs exhibited bright fluorescence, which was stable for several days under various pH. Confocal laser scanning microscopy revealed that the CDs could image HeLa cells with blue or green fluorescence well, and realize the monitoring of the gene delivery process. Besides, the CDs showed favorable biocompatibility with excellent performance in longitudinal relaxivity rates (r1) of 11.4 mM-1 s-1 for L-CD and 57.6 mM-1 s-1 for C-CD, which were about 3-15 times higher than that of the clinical Gd reagent Gd-DTPA (3.75 mM-1 s-1). Furthermore, the CDs could perform in vivo tumor-specific MR-imaging more clearly than Gd-DTPA, which is attributed to their suitable particle size and their resulting greater accumulation at tumor site via the EPR effect. This study provides a promising strategy for constructing multi-functional CDs for tumor theranostics.


Assuntos
Carbono , Meios de Contraste , Gadolínio DTPA , Imagem Multimodal , Neoplasias Experimentais/diagnóstico por imagem , Pontos Quânticos/química , Animais , Carbono/química , Carbono/farmacologia , Meios de Contraste/química , Meios de Contraste/farmacologia , Feminino , Gadolínio/química , Gadolínio/farmacologia , Gadolínio DTPA/química , Gadolínio DTPA/farmacologia , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Confocal , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Nanomedicina Teranóstica
12.
Mater Sci Eng C Mater Biol Appl ; 103: 109860, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31349463

RESUMO

This paper describes the design of stimuli-sensitive theranostic nanoparticles, composed of reduced graphene oxide (rGO) self-assembled on thermosensitive liposomes encapsulated doxorubicin (DOX) and carbon quantum dot (CQD) (CQD-DOX-rGO-Tlip). The rGO-Tlip particles have been observed to be flower-shaped objects. The thermoresponsive and theranostic potential of CQD-DOX-rGO-Tlips have been studied using differential scanning calorimetry (DSC), ultraviolet visible spectroscopy (UV-Vis), Raman spectroscopy and photoluminescent assays. The chemo-photothermal potential of rGO-Tlip on MD-MB-231 cells during NIR laser irradiation has been examined using MTT assay. Also, the ability of rGO-Tlip to be taken up by MD-MB-231 cells has been studied using confocal microscopy and flowcytometry. The results indicate that CQD-DOX-rGO-Tlips achieve a synergistic effect between photothermal therapy and chemotherapy for cancer treatment. Furthermore, online monitoring drug release is accomplished by studying the emission intensity of CQD while DOX released.


Assuntos
Doxorrubicina , Grafite , Hipertermia Induzida , Neoplasias/terapia , Fototerapia , Pontos Quânticos , Carbono/química , Carbono/farmacologia , Linhagem Celular Tumoral , Doxorrubicina/química , Doxorrubicina/farmacologia , Grafite/química , Grafite/farmacologia , Humanos , Lipossomos , Neoplasias/metabolismo , Neoplasias/patologia , Pontos Quânticos/química , Pontos Quânticos/uso terapêutico
13.
J Colloid Interface Sci ; 552: 583-596, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31163388

RESUMO

We have developed a one-pot synthesis of bio-carbon nanowires from the natural product sodium alginate at low temperature, without using any catalyst, for anticoagulation applications. Sodium alginate is carbonized and sulfated/sulfonated in situ by solid state heating of a mixture of sodium alginate and ammonium sulfite. By regulating the heating temperature and the ratio of ammonium sulfite to sodium alginate, we modulated the degree of sulfation/sulfonation and carbonization, as well as the morphology of the carbon nanomaterials. The core-shell sulfated/sulfonated bio-carbon nanowires (CNWsAlg@SOx) made by the reaction of a mixture of ammonium sulfite and sodium alginate with a mass ratio of 5 (ammonium sulfite to sodium alginate) at 165 °C for 3 h, exhibit strong inhibition of thrombin activity due to their ultrahigh binding affinity towards it (dissociation constant (Kd) = 8.7 × 10-11 M). The possible formation mechanism of the carbon nanowires has been proposed. The thrombin-clotting time delay caused by CNWsAlg@SOx is ∼ 170 times longer than that caused by sodium alginate. Hemolysis and cytotoxicity assays demonstrated the high biocompatibility of CNWsAlg@SOx. Furthermore, the thromboelastography of whole-blood coagulation and rat-tail bleeding assays further reveal that CNWsAlg@SOx have a much stronger anticoagulation activity than sodium alginate and naturally sulfated polysaccharides (e.g., fucoidan). Our results suggest that the low-temperature prepared, cost-effective, and highly biocompatible CNWsAlg@SOx show great potential as an efficient anticoagulant for the prevention and treatment of diseases associated with thrombosis.


Assuntos
Anticoagulantes/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Carbono/farmacologia , Nanofios/química , Trombina/antagonistas & inibidores , Alginatos/química , Alginatos/farmacologia , Animais , Anticoagulantes/química , Carbono/química , Estrutura Molecular , Tamanho da Partícula , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/farmacologia , Ratos , Sulfitos/química , Sulfitos/farmacologia , Propriedades de Superfície , Trombina/metabolismo
14.
J Colloid Interface Sci ; 552: 639-650, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31173992

RESUMO

In this work, a tumor-targeted and multi-stimuli responsive drug delivery system combining infrared thermal imaging of cells with thermo-chemotherapy was developed. Oxidized mesoporous carbon nanoparticles (MCNs-COOH) with high photothermal conversion ability (photothermal transduction efficiency η = 27.4%) in near-infrared (NIR) region were utilized to encapsulate doxorubicin (DOX). The outer surfaces of MCNs-COOH were capped with multifunctional carbon dots (CDHA) as simultaneous smart gatekeepers, a tumor targeting moiety and a fluorescent probe. NIR laser irradiation killed cancer cells through NIR-light induced hyperthermia, facilitated chemotherapeutic drug release and enhanced the sensitivity of tumor cells to drugs. The therapeutic efficacy in two-dimensional (2D) and three-dimensional (3D) cells demonstrated that MC-CDHA loading DOX (MC-CDHA/DOX) had good chemo-photothermal synergistic antitumor effects (combination index of CI = 0.448). The biodistribution and pharmacodynamics experiments of MC-CDHA/DOX in the 4T1 tumor model indicated that MCNs-COOH prolonged the residence time of DOX in tumor tissues and therefore actualized effective synergistic photothermal chemotherapy. By combining these excellent capabilities, the tumor-targeted and multi-stimuli responsive drug delivery system can be utilized as a visible nanoplatform for chemophotothermal synergistic therapy.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Materiais Biocompatíveis/farmacologia , Carbono/farmacologia , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Pontos Quânticos/química , Animais , Antibióticos Antineoplásicos/química , Materiais Biocompatíveis/química , Carbono/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Ensaios de Seleção de Medicamentos Antitumorais , Eritrócitos/efeitos dos fármacos , Raios Infravermelhos , Camundongos , Células NIH 3T3 , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Tamanho da Partícula , Fototerapia , Porosidade , Coelhos , Propriedades de Superfície , Distribuição Tecidual
15.
J Colloid Interface Sci ; 553: 228-238, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31212225

RESUMO

An assembly of hybrid hydrogel derived from Carbon Dot (CD), Protoporphyrin IX (PpIX) and DNA is reported here. PpIX and CD were covalently conjugated to 5'-phosphate termini of Cytosine (C) rich single strand DNA (ssDNA) separately. The CD-DNA-PpIX hybrid hydrogel was assembled through the formation of intercalated motif (i-motif) DNA network structure from CD-DNA and PpIX-DNA conjugates where CD act as crosslinkers in the hydrogel as well as energy donor to excite the photosensitizer (PS), PpIX. While hydrogel derived from only PpIX-DNA conjugate showed an inadequate sol-gel transition, the same could be precisely achieved from the CD-DNA-PpIX hybrid hydrogel by controlled pH adjustment. Distinct photophysical properties of CD and PpIX including fluorescence emission potentially enable tracking of the PS loading and hydrogel dissolution that was visually detectable under UV illumination. Reactive Oxygen Species (ROS) generation and subsequent killing of gram-positive bacteria (Staphylococcus aureus (S. aureus)) were observed following excitation of PpIX (acceptor) in the hybrid hydrogel either through energy transfer from CD or by direct irradiation of PpIX with visible light. Complete dissolution of hydrogel and sustained release of PpIX and subsequent ROS generation was achieved over 10-11 days that could kill S. aureus systematically. This study provides a promising strategy to address self-quenching and solubility of PS for its sustained release in Antimicrobial Photodynamic Therapy (A-PDT) applications through smart hydrogel formulation.


Assuntos
Antibacterianos/farmacologia , Carbono/farmacologia , DNA/farmacologia , Protoporfirinas/farmacologia , Pontos Quânticos/química , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/química , Carbono/química , DNA/química , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Processos Fotoquímicos , Fotoquimioterapia , Protoporfirinas/química , Propriedades de Superfície
16.
J Sci Food Agric ; 99(13): 6032-6041, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31226218

RESUMO

BACKGROUND: In order to inhibit microorganisms and improve storage quality of fresh-cut cucumber, fresh-cut cucumber was treated by carbon dots (CDs) from kelp/chitosan (CH) coating solution with CD concentrations of 0%, 1.5%, 3% and 4.5% and then packaged as well as stored at 4 °C for 15 days. The effect of CDs/CH coating on microorganisms and the quality of modified-atmosphere-packaged fresh-cut cucumber during storage were investigated. RESULTS: The CDs was monodispersed spherical morphology with size distribution of 0.54-0.83 nm. Interaction of CDs and CH had the generation of strong hydrogen bond. Inhibition zone diameters of CDs/CH coating against Staphylococcus aureus and Escherichia coli were enhanced with the increase of CD concentrations. Moreover, CDs/CH coating inhibited the growth of total number of colonies, mold, and yeast in modified-atmosphere-packaged fresh-cut cucumber during storage. A coating of 4.5% CDs/CH effectively reduced the losses of weight, firmness, and total soluble solids, the degradation of ascorbic acid content and flavor, and inhibited peroxidases activity, as well as decreased water mobility in fresh-cut cucumber during storage. CONCLUSION: The results indicated that a CDs/CH coating was helpful for inhibiting microorganisms and improving storage quality, and could be an effective method to prolong shelf life of fresh-cut cucumber. © 2019 Society of Chemical Industry.


Assuntos
Carbono/farmacologia , Quitosana/farmacologia , Cucumis sativus/efeitos dos fármacos , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Carbono/química , Quitosana/química , Cucumis sativus/microbiologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Embalagem de Alimentos , Conservação de Alimentos/instrumentação , Conservantes de Alimentos/química , Armazenamento de Alimentos , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Humanos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Paladar
17.
Environ Sci Pollut Res Int ; 26(24): 24683-24694, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31240662

RESUMO

The effects of plant-based carbon source addition on wastewater NO3--N removal and the involved microorganisms, especially denitrifying bacteria, were investigated. A synthetic wastewater (NO3--N, 15 mg/L) was treated through the batch experiment, which included three inoculation cycles (7 days/cycle), and was conducted at 25 °C. Four natural plant substrates, namely, rice straw (RS), wheat straw (WS), ryegrass (RG), and reed (RD), were used as carbon sources and supplemented at the rate of 1% (w/v). The results showed that both RS and WS performed well in promoting NO3--N removal (79.55-97.07%). While RG removed only 22.08% of NO3--N in the first cycle, the removal efficiency increased afterward (86.09-95.82%). Conversely, the NO3--N removal rate of RD decreased from 95.10 to 24.77% as a result of its low ability to supply carbon. With respect to the microorganisms, the RS treatment resulted in more bacteria and denitrifying genes such as narG, nirK, nirS, and norB than other treatments, while the highest number of nosZ gene copies was recorded in the WS treatment. Sequencing results revealed that Firmicutes (18.19-56.96%), Proteobacteria (38.82-74.80%), and Bacteroidetes (3.15-4.15%) were three dominant bacterial phyla for RS, WS, and RD treatments. Furthermore, the genera Enterobacter, Massilia, and Bacillus were the main denitrifying bacteria participating in the NO3--N removal. Furthermore, correlation analysis indicated that the denitrifying genus Sphingobacterium played an important role in enhancing nitrogen removal. This study suggested that RS is the superior plant-based carbon source for denitrifying bioreactors used in agricultural runoff treatment.


Assuntos
Carbono/farmacologia , Desnitrificação/efeitos dos fármacos , Proteobactérias/química , Reatores Biológicos , Carbono/química , Nitrogênio/química , Oryza , Águas Residuárias/química
18.
Artigo em Inglês | MEDLINE | ID: mdl-31248029

RESUMO

OBJECTIVES: To explore the health effects of indoor/outdoor carbonaceous compositions in PM2.5 on pulmonary function among healthy students living in the local university campus. METHODS: Daily peak expiratory flow (PEF) and forced expiratory volume in 1 second (FEV1) were measured among 37 healthy students in the morning and evening for four two-week periods. Concurrent concentrations of indoor and outdoor PM2.5 (particulate matter with an aerodynamic diameter ≤ 2.5µm), carbonaceous components in PM2.5, ambient temperature, and relative humidity in the study area were also obtained. Mixed-effects model was applied to evaluate the associations between carbonaceous components and lung function. Different lags for the carbonaceous components were investigated. RESULTS: In single-pollutant model, a 10 µg/m3 increase of indoor and outdoor EC (elemental carbon) associated with -3.93 (95%CI: -6.89, -0.97) L/min and -3.21 (95%CI: -5.67, -0.75) L/min change in evening PEF at lag 0 day, respectively. Also, a 10 µg/m3 increase of indoor and outdoor POC (primary organic carbon) concentration was significantly associated with -5.82 (95%CI: -10.82, -0.81) L/min and -7.32 (95%CI: -12.93, -1.71) L/min change of evening PEF at lag 0 day. After adjusting total mass of PM2.5, indoor EC consistently had a significant adverse impact on evening PEF and FEV1 at lag3 day and a cumulative effect at lag0-3 day. CONCLUSIONS: This study suggests that carbonaceous components in PM2.5 indeed have impacts on pulmonary function among healthy young adults especially on evening PEF. Thus, the local mitigation strategies on pollution are needed.


Assuntos
Poluentes Atmosféricos/farmacologia , Carbono/farmacologia , Pulmão/efeitos dos fármacos , Material Particulado/farmacologia , Poluentes Atmosféricos/análise , Carbono/análise , China , Feminino , Humanos , Umidade , Masculino , Material Particulado/análise , Testes de Função Respiratória , Temperatura , Adulto Jovem
19.
Int J Radiat Biol ; 95(9): 1346-1350, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31140908

RESUMO

Purpose: Our previous study revealed that the application of a magnetic field longitudinal to a carbon-ion beam of 0.1 ≤ B//≤ 0.6 T enhances the biological effectiveness of the radiation. The purpose of this study is to experimentally verify whether the application of a magnetic field perpendicular to the beam also alters the biological effectiveness. Methods and materials: Most experimental conditions other than the magnetic field direction were the same as those used in the previous study to allow comparison of their results. Human cancer and normal cells were exposed to low (12 keV/µm) and high (50 keV/µm) linear energy transfer (LET) carbon-ion beams under the perpendicular magnetic fields of B⊥ = 0, 0.15, 0.3, or 0.6 T generated by a dipole magnet. The effects of the magnetic fields on the biological effectiveness were evaluated by clonogenic cell survival. Doses that would result in the survival of 10%, D10s, were determined for the exposures and analyzed using Student's t-tests. Results: For both cancer and normal cells treated by low- and high-LET carbon-ion beams, the D10s measured in the presence of the perpendicular magnetic fields of B⊥ ≥ 0.15 T were not statistically different (p ≫ .05) from the D10s measured in the absence of the magnetic fields, B⊥ = 0 T. Conclusions: Exposure of human cancer and normal cells to the perpendicular magnetic fields of B⊥ ≤ 0.6 T did not alter significantly the biological effectiveness of the carbon-ion beams, unlike the exposure to longitudinal magnetic fields of the same strength. Although the mechanisms underlying the observed results still require further exploration, these findings indicate that the influence of the magnetic field on biological effectiveness of the carbon-ion beam depends on the applied field direction with respect to the beam.


Assuntos
Carbono/farmacologia , Campos Magnéticos , Sobrevivência Celular/efeitos da radiação , Radioterapia com Íons Pesados , Humanos , Transferência Linear de Energia/efeitos dos fármacos , Transferência Linear de Energia/efeitos da radiação
20.
Drug Discov Ther ; 13(2): 114-117, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31080202

RESUMO

Carbon dots prepared from different sources have been widely studied in various medical applications. Those dots have been reported to be able to inhibit the proliferation of cancer cells, such as prostate cancer cells. The current study used carbon dots prepared from red beans to determine their effect on 16 cell lines including liver cancer cells, pancreatic cancer cells, intrahepatic cholangiocarcinoma cells, and colorectal adenocarcinoma cells. In a cellular viability experiment, carbon dots were found suppress cancer cell viability in a time- and dose-dependent manner. In a cell migration experiment, cancer cells treated with carbon dots had less ability to heal, suggesting that carbon dots inhibit cell migration. In another cellular viability experiment, a combination of carbon dots and doxorubicin resulted in greater inhibition than cells treated with either therapy alone. These findings suggest that carbon dots could be an alternative and complementary medicine for the treatment of cancers.


Assuntos
Antineoplásicos/farmacologia , Carbono/farmacologia , Doxorrubicina/farmacologia , Vigna/química , Antineoplásicos/química , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carbono/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Extratos Vegetais/química , Pontos Quânticos
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