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1.
ACS Appl Mater Interfaces ; 13(47): 55928-55938, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34786942

RESUMO

The synergy of chemodynamic therapy (CDT) and photothermal therapy (PTT) can improve anticancer efficacy, while the limited diffusion distance and the short lifetime of •OH still greatly restrict the therapeutic efficacy of PTT-CDT. Herein, MoS2@PDA-Fe@PEG/TPP (MPFPT) nanosheets (NSs) with mitochondria-targeting ability were reported for enhanced PTT-CDT synergistic oncotherapy. MPFPT NSs were prepared by covalent modification of poly(ethylene glycol) (PEG) and triphenylphosphonium (TPP) on polydopamine (PDA)-Fe3+coated MoS2 NSs. Co-localization experiments showed that MPFPT NSs can efficiently target mitochondria via the direction of TPP. Moreover, MPFPT NSs have good photothermal performance in the second near-infrared (NIR-II) region and can greatly accelerate the Fenton reaction from H2O2 to generate more hydroxyl radicals (•OH). In vitro experimental results showed that MPFPT NSs have improved therapeutic efficacy to cancer cells than similar MoS2-based nanoagents without mitochondria-targeting units, which can be attributed to the short distance between mitochondria and MPFPT NSs and the efficient damage of mitochondria by in situ generated •OH. In the 4T1 tumor-bearing mice model, MPFPT NSs demonstrated significantly enhanced therapeutic efficacy by PTT-CDT, suggesting the superiority of the mitochondria-targeting strategy. This study reveals that mitochondria-targeting MPFPT NSs are promising nanoagents for oncotherapy.

2.
J Colloid Interface Sci ; 608(Pt 2): 1393-1400, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34742060

RESUMO

Herein, a feasible outside-in hydrothermal self-transformation strategy is presented to fabricate hierarchically porous benzene-bridged organosilica nanoparticles (HPBONs), and detailed mechanistic investigations were performed to study the formation of hierarchically porous nanostructures. The obtained HPBONs consisted of a mesoporous core (2.3 nm) and a large mesoporous flocculent shell (12.6 nm), which corresponded to an overall diameter of âˆ¼ 200 nm and good water dispersibility, respectively. Owing to the unique hierarchically porous structure and high surface area (877 m2/g), HPBONs showed a high coloading capacity for the hydrophilic drug doxorubicin (DOX) and the hydrophobic photosensitizer chlorin e6 (Ce6) (355 µg/mg, 38 µg/mg, respectively) and acid-responsive DOX drug release (42.62%), leading to precise chemo-photodynamic therapy in vitro, as the cytotoxicity assay revealed 70% killing of breast cancer (MCF-7) cells. This research provides a new method to construct hierarchically porous organosilica-based nanodelivery systems.

3.
Mater Horiz ; 8(4): 1264-1271, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-34821919

RESUMO

Bacterial biofilm infections are intractable to traditional antibiotic treatment and usually cause persistent inflammation. Chemodynamic therapy (CDT) based on the Fenton reaction has recently emerged as a promising anti-biofilm strategy. However, the therapeutic efficacy of current Fenton agents often suffers from inefficient Fenton activity and lacks anti-inflammatory capability. Herein, FePS3 nanosheets (NSs) are explored for the first time as novel microenvironment-selective therapeutic nanoagents for bacterial biofilm infections with both self-enhanced Fenton activity for an anti-biofilm effect and reactive oxygen species (ROS) scavenging properties for an anti-inflammatory effect. In biofilms with acidic microenvironments, FePS3 NSs release Fe2+ to generate toxic ROS by Fenton reaction and reductive [P2S6]4- to enhance the Fenton activity by reducing Fe3+ to Fe2+. In the surrounding normal tissues with neutral pH, FePS3 NSs scavenge ROS by reductive [P2S6]4- with an anti-inflammatory effect. This work demonstrates multifunctional Fenton nanoagents with microenvironment-selective ROS generation and elimination properties for effective treatment of bacterial biofilm infections with both anti-biofilm and anti-inflammatory effects.

4.
Biomater Sci ; 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34782897

RESUMO

Furin is an important cellular endoprotease, which is expressed at high levels in various cancer cells. Accurate and real-time detection of endogenous furin with high sensitivity and selectivity is significant for the diagnosis of cancer. Herein an activatable nanoprobe (MoS2@PDA-PEG/peptide, MPPF) with dual-mode near-infrared fluorescence (NIRF)/ratiometric photoacoustic (PA) imaging of endogenous furin activity has been developed. The MPPF nanoprobes were constructed by the covalent functionalization of polydopamine (PDA) coated MoS2 nanosheets (NSs) with Cy7-labeled furin substrate peptides. Upon cleavage of the peptides by furin, Cy7 molecules are released from MPPF nanoprobes and recover their fluorescence, realizing furin activity detection with the limit of detection (LOD) down to 3.73 × 10-4 U mL-1. Meanwhile, the ratio of the PA signal at 768 nm to that at 900 nm (PA768/PA900) decreases over time due to the destruction of fluorescence resonance energy transfer effect from Cy7 to MoS2 NSs and the rapid clearance of small Cy7 molecules from tissues. Thus, the simultaneous change in NIRF and ratiometric PA signals enables the imaging of endogenous furin activity in real time, and with high sensitivity, and high selectivity in both tumor cells and tumor-bearing mice.

5.
ACS Appl Mater Interfaces ; 13(43): 51297-51311, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34668372

RESUMO

Artificial nanomotors are undergoing significant developments in several biomedical applications. However, current experimental strategies for producing nanomotors still have inherent drawbacks such as the requirement for expensive equipment, strict controlling of experimental conditions, and strenuous processes with several complex procedures. In this study, we describe for the first time a facile single-step thermodynamic-controlled coating method to prepare Janus mesoporous organosilica nanomotors. By controlling the total free energy of organosilica oligomers (G) from a low development level to a high level in the reaction system, the nonspontaneous nucleation on the platinum (Pt) nanosurface and the spontaneous nucleation in a solvent can be controlled, respectively. More importantly, we reveal that the molecular arrangement and contact angle of deposited organosilica on Pt cores vary with the total free energy of organosilica oligomers (G). Different values of θ would change the trend of detachment from Pt for organosilica nucleated cores and carry out diverse coating modes. These are indicated by the morphology evolution of platinum/organosilica hybrids, from naked platinum nanoparticles, evenly distributed organosilica shell/core, nonconcentric to typical Janus nanomotor. The prepared Janus mesoporous nanomotor (JMN) showed typical mesopore structures and active propelling behaviors under H2O2 stimulation. In addition, the JMN modified with hyaluronic acid exhibited excellent biocompatibility and improved tumor penetration under H2O2 stimulation. The successful construction of other nanomotor frameworks based on a gold-templated core proves the perfect applicability of the thermodynamic-coating method for the production of nanomotors. In conclusion, this work establishes a manufacturing methodology for nanomotors and drives nanomotors for promising biomedical applications.

6.
Chem Commun (Camb) ; 57(86): 11318-11321, 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34635891

RESUMO

Utilizing the programmability of the fractal DNA frameworks, multi-color probes were constructed by arranging fluorescent molecules and nucleic acid aptamers on the structure. Multiplexed cell imaging and classification was realized through pattern recognition.

7.
Nanoscale ; 13(34): 14417-14425, 2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34473184

RESUMO

The recurrence and metastasis of tumor after surgery is the main cause of death for patients with breast cancer. Systemic chemotherapy suffered from low delivery efficiency to tumors and the side effects of chemo drugs. Localized chemotherapy using drug-containing implants is an alternative, while the reconstruction of breast tissue is generally considered after chemotherapy, resulting in a second surgery for patients. Here, we describe a strategy using implantable drug-containing polymeric scaffolds to deliver chemo drugs directly to the post-resection site, and simultaneously provide mechanical support and regenerative niche for breast tissue reconstruction. When doxorubicin was loaded in mesoporous silica nanoparticles and subsequently incorporated into polycaprolactone scaffolds (DMSN@PCL), a 9-week sustained drug release was achieved post implantation in mice. The local recurrence of residual tumor after surgery was significantly inhibited within 4 weeks in a post-surgical mouse model bearing xenograft MDA-MB-231 tumor. DMSN@PCL scaffolds exhibited good biocompatibility in mice during the treatment. We believe our strategy holds great promise as an adjuvant localized chemotherapy in clinics for combating post-resection breast cancer recurrence.


Assuntos
Antineoplásicos , Neoplasias da Mama , Nanopartículas , Animais , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Doxorrubicina/uso terapêutico , Feminino , Humanos , Camundongos , Poliésteres
8.
ACS Omega ; 6(36): 23076-23082, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34549108

RESUMO

The merge between nanophotonics and a deep neural network has shown unprecedented capability of efficient forward modeling and accurate inverse design if an appropriate network architecture and training method are selected. Commonly, an iterative neural network and a tandem neural network can both be used in the inverse design process, where the latter is well known for tackling the nonuniqueness problem at the expense of more complex architecture. However, we are curious to compare these two networks' performance when they are both applicable. Here, we successfully trained both networks to inverse design the far-field spectrum of plasmonic nanoantenna, and the results provide some guidelines for choosing an appropriate, sufficiently accurate, and efficient neural network architecture.

9.
Inorg Chem ; 60(19): 14810-14819, 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34546744

RESUMO

Three tris-heteroleptic mononuclear Ru(II) complexes with dual fluorescence and phosphorescence-[Ru(dpma)(bpy)(phen)]2+ (12+), [Ru(dpma)(bpy)(dppz)]2+ (22+), and [Ru(dpma)(phen)(dppz)]2+ (32+)-have been designed and used as ratiometric light-response probes for DNA, where dpma is di(pyrid-2-yl)(methyl)-amine, bpy is 2,2'-bipyridine, phen is 1,10-phenanthroline, and dppz is dipyridophenazine, respectively. Single crystals of complex 2(PF6)2 have been obtained and studied by X-ray analysis. The interactions of these complexes with different DNAs are investigated by means of spectroscopic methods, viscosity measurements, and molecular modeling. In the presence of calf thymus DNA, complexes 2(PF6)2 and 3(PF6)2 show the emergence of a new lower-energy phosphorescence emission band; meanwhile, the higher-energy fluorescence emission band is essentially unchanged, functioning as an intrinsic internal reference. These two complexes exhibit stronger preference for calf thymus DNA over single-strand DNA (d(A)16 and d(C)16). In contrast, no binding interaction between 1(PF6)2 and calf thymus DNA is observed. The intrinsic binding constants (Kb) of 2(PF6)2 and 3(PF6)2 with calf thymus DNA are determined to be (1.4 ± 0.4) × 105 and (9.5 ± 0.15) × 104 M-1, respectively. In addition, these spectroscopic results are compared with those of the prototype complex [Ru(bpy)2(dppz)]2+ (42+), and density functional theory and time-dependent density functional theory calculations are employed to elucidate these experimental findings.


Assuntos
Complexos de Coordenação/química , DNA/química , Rutênio/química , Animais , Bovinos , Estrutura Molecular
10.
Anal Chem ; 93(41): 13861-13869, 2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34506117

RESUMO

Accurate, specific, and inexpensive detection of multiple infectious pathogens simultaneously is a significant goal for human health and safety. Herein we present a rationally designed modular DNA circuit for point-of-care (POC) detection of a variety of infectious pathogens based on nucleic acid isothermal amplification technology and DNAzyme-mediated colorimetric readout. A modular DNA circuit was constructed with a fixed module and a flexible module and was rationally designed according to genetic targets. On this basis, the platform could detect multiple genetic targets corresponding to infectious pathogens simultaneously. Signal amplification properties of the DNA circuit and the peroxidase-like DNAzyme enable the detection limits to reach the picomolar level. By urea treatment and magnetic separation, the fixed module can be reused at least five times, which makes this assay more economical and environmentally friendly. The detection of genetic infectious pathogens should be accomplished in 2 h with naked-eye observation and may provide an efficient tool for POC analysis of multiple infectious pathogens, especially in resource-poor areas.


Assuntos
Técnicas Biossensoriais , DNA Catalítico , Colorimetria , DNA/genética , Humanos , Técnicas de Amplificação de Ácido Nucleico , Sistemas Automatizados de Assistência Junto ao Leito
11.
Adv Sci (Weinh) ; 8(17): e2100386, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34247445

RESUMO

Broadband near-infrared (NIR) photothermal and photoacoustic agents covering from the first NIR (NIR-I) to the second NIR (NIR-II) biowindow are of great significance for imaging and therapy of cancers. In this work, ultrathin two-dimensional plasmonic PtAg nanosheets are discovered with strong broadband light absorption from NIR-I to NIR-II biowindow, which exhibit outstanding photothermal and photoacoustic effects under both 785 and 1064 nm lasers. Photothermal conversion efficiencies (PCEs) of PtAg nanosheets reach 19.2% under 785 nm laser and 45.7% under 1064 nm laser. The PCE under 1064 nm laser is higher than those of most reported inorganic NIR-II photothermal nanoagents. After functionalization with folic acid modified thiol-poly(ethylene glycol) (SH-PEG-FA), PtAg nanosheets endowed with good biocompatibility and 4T1 tumor-targeted function give high performances for photoacoustic imaging (PAI) and photothermal therapy (PTT) in vivo under both 785 and 1064 nm lasers. The effective ablation of tumors in mice can be realized without side effects and tumor metastasis by PAI-guided PTT of PtAg nanosheets under 785 or 1064 nm laser. The results demonstrate that the prepared PtAg nanosheets with ultrathin thickness and small size can serve as a promising phototheranostic nanoplatform for PAI-guided PTT of tumors in both NIR-I and NIR-II biowindows.

12.
Talanta ; 232: 122182, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34074380

RESUMO

Lanthanide nanoprobes have attracted extensive attention for applications in cellular imaging and biological sensing. Herein, water-dispersible europium (III)-based (Eu(III)-based) nanoprobes were prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization-induced self-assembly (PISA) of hydrophobic monomers (Eu(III)-containing monomer and methyl methacrylate (MMA)) using hydrophilic macro-chain transfer agent poly(PEGMA)-CTA. The resulted poly(PMEu) nanoprobes showed spherical in shape in good monodispersity with average diameters of around 210 nm. The poly(PMEu) nanoprobles excellent aqueous dispersity, high aqueous stability and good luminescence properties with quantum yields of 37.21% and fluorescence lifetime of 312.4 µs. Moreover, the poly(PMEu) nanoprobes exhibited good cellular biocompatibility with cell viabilities of 88.2% and high fluorescence intensity for in vitro cellular imaging. The present approach provides a facile strategy for fabrication of luminescent Eu(III)-based nanoprobes with great potential applications for biological imaging.


Assuntos
Európio , Nanopartículas , Polimerização , Polímeros , Água
13.
Chem Sci ; 12(22): 7727-7734, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-34168825

RESUMO

Aggregation-induced emission (AIE) based fluorophores (AIEgens) have attracted increasing attention for biomedical applications due to their unique optical properties. Here we report an AIE photosensitizer functionalized CB[7], namely AIECB[7], which could spontaneously self-assemble into nanoaggregates in aqueous solutions. Interestingly, the carbonyl-lace of CB[7] may potentially act as a proton acceptor in an acidic environment to fine-tune the fluorescence and singlet oxygen generation of AIECB[7] nanoaggregates by regulating the inner stacking of AIEgens. Additionally, benefiting from the guest-binding properties of CB[7], oxaliplatin was included into AIECB[7] nanoaggregates for combined photodynamic therapy and supramolecular chemotherapy. To show the modular versatility of this supramolecular system, a hypoxia-activatable prodrug banoxantrone (AQ4N) was loaded into AIECB[7] nanoaggregates, which exhibited synergistic antitumor effects on a multicellular tumor spheroid model (MCTS). This work not only provides AIECB[7] for versatile theranostic applications, but also offers important new insights into the design and development of macrocycle-conjugated AIE materials for diverse biomedical applications.

14.
Biosens Bioelectron ; 190: 113376, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34098358

RESUMO

Highly sensitive and reliable detection of disease-related nucleic acids is still a big challenge in liquid biopsy because of their homologous sequences and low abundance. Herein, a novel surface plasmon resonance/surface-enhanced Raman scattering (SPR/SERS) dual-mode plasmonic biosensor based on catalytic hairpin assembly (CHA)-induced Au nanoparticle (AuNP) network was proposed for highly sensitive and reliable detection of cancer-related miRNA-652. The biosensor includes capture DNA-functionalized AuNPs (Probe 1), H1 and 4-mercaptobenzoic acid (4-MBA) co-modified AuNPs (Probe 2), and 6-carboxyl-Xrhodamine (ROX)-labeled H2 (fuel strands). The Probe 1-Probe 2 networks were formed via the target-triggered CHA reactions, which resulted in the color change of dark-field microscopy (DFM) images and enhanced SERS effect. The SPR sensing was achieved by extracting the integral optical density of dark-field color in DFM images, and the SERS sensing was realized by the ratiometric SERS signals of ROX and internal standards 4-MBA molecules. After characterizing the feasibility and optimality of the sensing strategy, the good performance of biosensors on sensitivity, specificity and uniformity was approved. The practicability of biosensors was confirmed by detecting miRNA-652 in human serum, and both the SPR and SERS assays showed good linear calibration curves and low limit of detections (LODs) of 42.5 fM and 2.91 fM, respectively, with the recovery in the range of 94.67-111.4%. These two modes show complementary advantages, and the combined SPR/SERS dual-mode can provide more options for detection and double check the results to improve the accuracy and reliability of assays, which holds a great application prospect for cancer-related nucleic acids detection in early disease stage.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Ouro , Humanos , Limite de Detecção , Reprodutibilidade dos Testes , Análise Espectral Raman , Ressonância de Plasmônio de Superfície
15.
Carbohydr Polym ; 268: 118257, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34127228

RESUMO

Multifunctional theranostic nanoplatforms integrated of imaging function, multi-modality therapy, stimuli-responsiveness, and targeted delivery are of highly desirable attributes in achieving precise medicine. However, preparation of multifunctional nanoplatforms often involves laborious, multiple steps and inevitably utilizes low-biocompatible or non-functional components. Herein we report a facile, one-step self-assembly strategy to fabricate hyaluronic acid (HA)-based multifunctional tumor theranostic nanoplatform by employing magnetic resonance imaging (MRI) agent Mn2+ as a reversible crosslink agent for histidine-grafted HA, along with simultaneously loading chemotherapeutic agent doxorubicin hydrochloride (DOX) and photodynamic therapy agent chlorin e6, to realize MRI-guided targeted chemo-photodynamic cancer therapy. The targeted delivery and stimuli-responsive payload release were demonstrated in vitro and in vivo. Furthermore, the combined chemo-photodynamic therapy of the nanoassembly dramatically improved the cancer therapeutic outcome, in comparison with that of free DOX and nanoplatform solely loaded DOX in a melanoma bearing mice. Our one step assemble strategy is of great potential in clinic transformation.


Assuntos
Antineoplásicos/uso terapêutico , Portadores de Fármacos/química , Nanogéis/química , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Animais , Linhagem Celular Tumoral , Doxorrubicina/uso terapêutico , Portadores de Fármacos/toxicidade , Histidina/química , Histidina/toxicidade , Ácido Hialurônico/análogos & derivados , Ácido Hialurônico/toxicidade , Luz , Manganês/química , Manganês/toxicidade , Camundongos Endogâmicos C57BL , Nanogéis/toxicidade , Fotoquimioterapia , Fármacos Fotossensibilizantes/efeitos da radiação , Porfirinas/efeitos da radiação , Porfirinas/uso terapêutico , Medicina de Precisão/métodos , Oxigênio Singlete/metabolismo
16.
Biomater Sci ; 9(12): 4484-4495, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34002742

RESUMO

Infectious diseases associated with antibiotic-resistant bacteria are ever-growing threats to public health. Effective treatment and detection methods of bacterial infections are in urgent demand. Herein, novel phototheranostic nanoagents (MoS2@HA-Ce6 nanosheets, MHC NSs) with hyaluronidase (HAase)-responsive fluorescence imaging (FLI) and photothermal/photodynamic therapy (PTT/PDT) functions were prepared. In this design, Ce6 is used as both a photosensitizer and a fluorescent probe, while MoS2 nanosheets (MoS2 NSs) serve as both a fluorescence quencher and a photothermal agent. Hyaluronic acid conjugated with Ce6 (HA-Ce6) was assembled on the surface of MoS2 NSs to form MHC NSs. Without the HAase secreted by methicillin-resistant Staphylococcus aureus (MRSA), the fluorescence of Ce6 is quenched by MoS2 NSs, while in the presence of MRSA, HAase can degrade the HA and release Ce6, which restores the fluorescence and photodynamic activity of Ce6. The experimental results show that MHC NSs can fluorescently image the MRSA both in vitro and in vivo by HAase activation. Meanwhile, MHC NSs can serve as PTT/PDT dual-mode antibacterial agents for MRSA. In vitro antibacterial results show that MHC NSs can kill 99.97% MRSA under 635 nm and 785 nm laser irradiation. In vivo study further shows that MHC NSs can kill 99.9% of the bacteria in MRSA infected tissues in mice and prompt wound healing by combined PTT/PDT. This work provides novel HAase-responsive phototheranostic nanoagents for effective detection and treatment of bacterial infections.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Fotoquimioterapia , Animais , Hialuronoglucosaminidase , Camundongos , Imagem Óptica , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico
17.
Biosens Bioelectron ; 187: 113329, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34020223

RESUMO

Coronavirus disease 2019 (COVID-19) as a severe acute respiratory syndrome infection has spread rapidly across the world since its emergence in 2019 and drastically altered our way of life. Patients who have recovered from COVID-19 may still face persisting respiratory damage from the virus, necessitating long-term supervision after discharge to closely assess pulmonary function during rehabilitation. Therefore, developing portable spirometers for pulmonary function tests is of great significance for convenient home-based monitoring during recovery. Here, we propose a wireless, portable pulmonary function monitor for rehabilitation care after COVID-19. It is composed of a breath-to-electrical (BTE) sensor, a signal processing circuit, and a Bluetooth communication unit. The BTE sensor, with a compact size and light weight of 2.5 cm3 and 1.8 g respectively, is capable of converting respiratory biomechanical motions into considerable electrical signals. The output signal stability is greater than 93% under 35%-81% humidity, which allows for ideal expiration airflow sensing. Through a wireless communication circuit system, the signals can be received by a mobile terminal and processed into important physiological parameters, such as forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC). The FEV1/FVC ratio is then calculated to further evaluate pulmonary function of testers. Through these measurement methods, the acquired pulmonary function parameters are shown to exhibit high accuracy (>97%) in comparison to a commercial spirometer. The practical design of the self-powered flow spirometer presents a low-cost and convenient method for pulmonary function monitoring during rehabilitation from COVID-19.


Assuntos
Técnicas Biossensoriais , COVID-19 , Humanos , SARS-CoV-2 , Espirometria , Capacidade Vital
18.
Biomater Sci ; 9(10): 3804-3813, 2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-33881050

RESUMO

Nano-graphene oxide (NGO) has attracted increasing attention as an advanced drug delivery system. However, the current surface functionalization and drug-loading of NGO either rely on π-π stacking that is limited to aromatic molecules, or covalent conjugation that requires tedious synthesis. Herein, we developed the first cucurbit[7]uril (CB[7])-conjugated NGO (NGO-CB[7]) that allows non-covalent, modular surface functionalization and drug loading via not only traditional π-π stacking interactions between the NGO surface and functional molecules, but also strong host-guest interactions between CB[7] and guest payloads or adamantane (ADA)-tagged functional molecules, for more versatile biomedical applications. To this end, chlorin e6 (Ce6, a photosensitizer), banoxantrone dihydrochloride (AQ4N, a hypoxia-responsive prodrug) and oxaliplatin (OX, a guest of CB[7]) were co-loaded onto NGO-CB[7] via π-π stacking and host-guest interactions, respectively. Subsequently, ADA-tagged hyaluronic acid (ADA-HA) wrapped NGO-CB[7] non-covalently via CB[7]-ADA host-guest interactions to improve the physiological stability and overall biocompatibility of this supramolecular nanosystem, and to enable targeted delivery into cancer cells with CD44 receptors overexpressed. Remarkably, this supramolecular nanomedicine exhibited significant antitumor efficacy via combined photothermal/photodynamic therapy (PTT/PDT) from NGO/Ce6, as well as dual chemotherapy from OX and AQ4N (activated by PDT-enhanced hypoxia), in vitro and in vivo. This study not only offers a new supramolecular inorganic/organic hybrid nanosystem for multi-modality cancer therapy, but may also provide important new insights into noncovalent functionalization of other carbon nanomaterials and inorganic nanomaterials leading to multifunctional drug delivery systems.


Assuntos
Nanomedicina , Neoplasias , Hidrocarbonetos Aromáticos com Pontes , Imidazóis , Neoplasias/tratamento farmacológico , Óxidos
19.
J Org Chem ; 86(9): 6423-6432, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33905254

RESUMO

A novel copper-catalyzed cyclization of readily available vinyl azides with CF3-ynones is steadily achieved under mild conditions to furnish the versatile 2,4-diaryl-6-trifluoromethylated pyridine products, which are of great interest in medicinal chemistry. The generation of the vinyl iminophosphorane intermediates from vinyl azides through the Staudinger-Meyer reaction ensures the subsequent 1,4-addition process with CF3-ynones in this transformation.


Assuntos
Azidas , Cobre , Catálise , Ciclização , Piridinas
20.
Chem Commun (Camb) ; 57(31): 3801-3804, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33876126

RESUMO

The mechanism underlying the strong adhesion between DNA with consecutive adenines (polyA) and Au nanoparticles (AuNPs) is experimentally and theoretically studied. We elucidate that the consecutive adenines collectively result in hydrophobic collapse in the adhesion process, which plays a pivotal role for the high adhesion affinity and specificity.


Assuntos
DNA/química , Ouro/química , Nanopartículas Metálicas/química , Poli A/química , Teoria da Densidade Funcional , Interações Hidrofóbicas e Hidrofílicas , Simulação de Dinâmica Molecular
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