修车大队一品楼qm论坛51一品茶楼论坛,栖凤楼品茶全国楼凤app软件 ,栖凤阁全国论坛入口,广州百花丛bhc论坛杭州百花坊妃子阁

oe1(光电查) - 科学论文

95 条数据
?? 中文(中国)
  • Graphene quantum dot based charge-reversal nanomaterial for nucleus-targeted drug delivery and efficiency controllable photodynamic therapy

    摘要: Graphene quantum dots (GQD), the new zero-dimensional carbon nanomaterial, has been demonstrated as a promising material for biomedical applications due to its good biocompatibility and low toxicity. However, the integration of multiple therapeutic approaches into a nano-sized platform based on the GQD has not been explored yet to our best knowledge. In this report, we regulate the generation of reactive oxygen species (ROS) when using the GQD as a photosensitizer by varying the doping amount of nitrogen atoms to achieve efficiency controllable photodynamic therapy (PDT). On the other hand, charge-reversal (3-Aminopropyl) triethoxysilane (APTES) was employed to conjugate on the surface of GQD for nucleus targeting drug delivery for the first time. The treatment outcome of produced ROS and nucleus-targeting drug delivery was investigated by fluorescence imaging. The results demonstrated that the N-GQD-DOX-APTES in dual roles as a drug carrier and photosensitizer could achieve nucleus-targeting delivery and strong ROS production simultaneously. This approach provides a promising strategy for the development of multifunctional therapy in one nano platform for biomedical applications.

    关键词: nucleus-targeted drug delivery,Graphene quantum dots,nitrogen doped graphene quantum dots,charge-reversal,photodynamic therapy

    更新于2025-11-21 11:24:58

  • Self-Assembled Nanostructures of Red Fluorescent Amphiphilic Block Copolymers as Both Imaging Probes and Drug Carriers

    摘要: We report a red-?uorescent drug delivery system formed by biodegradable and biocompatible amphiphilic A-B-A block copolymers. Each polymer consists of a red ?uorescent dye covalently bonded in the middle of hydrophobic block (B) of polylactone, tethered at both ends with poly[(oligo ethylene glycol) methyl ether methacrylate] (POEGMA) as the hydrophilic block. Two types of polylactones, i.e., semicrystalline poly(ε-caprolactone) (PCL) and amorphous poly(δ-decalactone) (PDL), respectively, were incorporated as the hydrophobic segment in the block copolymers. Using transmission electron microscopy, we characterized the self-assembled nanostructures formed by these amphiphilic block copolymers in mixtures of water/tetrahydrofuran or water/dimethylformamide. All of these polymers remained highly ?uorescent in water, although some extent of aggregation-induced ?uorescence quenching was still observed. Among the three types of polymers presented here, the polymer (RPO-3) containing an amorphous block of PDL showed the highest drug-loading capacity and the largest extent of drug release in acidic media. RPO-3 micelles loaded with doxorubicin as a model of anticancer drug showed sustainable intracellular release and cytotoxicity against HeLa cells.

    关键词: self-assembly,drug delivery,polymer,?uorescence,bioimaging

    更新于2025-11-21 11:08:12

  • Evaluation of various tissue-clearing techniques for the three-dimensional visualization of liposome distribution in mouse lungs at the alveolar scale

    摘要: Purpose: To develop a three-dimensional visualization method for evaluating the distribution of pulmonary drug delivery systems and compare four tissue-clearing techniques (ClearT2, CUBIC, ScaleS, and SeeDB2) using intrapulmonary liposomes as drug carriers. Methods: Rhodamine B-labeled liposomes were administered intrapulmonarily to mice using a MicroSprayer, and then fluorescent-labeled tomato lectin was administered intravenously to visualize the general lung structure. Tissue-clearing treatment of the mouse lungs was performed using the standard protocols of the ClearT2, CUBIC, ScaleS, and SeeDB2 techniques. Lung clearing was clarified using laser-scanning confocal microscopy, and three-dimensional images were reconstructed. Results: Fluorescent-labeled tomato lectin was preserved using ClearT2 and SeeDB2 but not using CUBIC and ScaleS. In addition, the liposomes were stable in ClearT2 reagent, but they were mostly degraded in other reagents by surface-active agents. ClearT2 treatment enabled the three-dimensional visualization of intrapulmonary rhodamine B-labeled liposomes at the alveolar scale. Conclusions: These results suggest that the ClearT2 tissue-clearing technique was appropriate for the three-dimensional visualization of intrapulmonary liposomes at the alveolar scale. This study provides important information for selecting and optimizing suitable optical tissue-clearing techniques in lungs for evaluating the distribution of pulmonary drug delivery systems.

    关键词: fluorescence preservation,Intrapulmonary distribution,inhalation,liposomes,drug delivery systems,laser-scanning confocal microscopy

    更新于2025-11-21 11:08:12

  • Graphene quantum dots nanoparticles changed the rheological properties of hydrophilic gels (carbopol)

    摘要: Graphene quantum dots (GQDs) have special properties at nanosize zone, as highly tunable photoluminescence, electrochemiluminescence and multiphoton excitation, that make them promising nanoagents for drug delivery systems. In this direction the use of gels to formulate nanodrugs, for both in vitro and in vivo assay is required. However, the presence of GQDs nanoparticles may affect the rheological parameters. These changes may influence the biological behavior of this formulation as change the pharmacological application. In this study we evaluated the effect of adding GQDs to carbopol gels formulation, in terms of rheological properties. In this direction, carbopol gels alone and loaded with GQDs were studied. The results of pure carbopol formulation showed a non-Newtonian, pseudo-plastic fluid without thixotropic behavior. Otherwise, the presence of GQDs in the carbopol formulation (carbopol loaded with GQDs) caused a reduction on the viscosity and modified the interactions between the polymer chains leading to the transformation of the initial gel into a viscous fluid. This alteration can change drastically the use of these formulations, especially for drug delivery, since slightly changes in viscosity can influence the occlusion, retention and permeability of these nanoparticles into biological barriers.

    关键词: Rheological properties,Drug delivery,Graphene quantum dots,Hydrogels,Carbopol

    更新于2025-11-19 16:56:42

  • In Situ Synthesis of Fluorescent Mesoporous Silica–Carbon Dot Nanohybrids Featuring Folate Receptor-Overexpressing Cancer Cell Targeting and Drug Delivery

    摘要: Multifunctional nanocarrier-based theranostics is supposed to overcome some key problems in cancer treatment. In this work, a novel method for the preparation of a fluorescent mesoporous silica–carbon dot nanohybrid was developed. Carbon dots (CDs), from folic acid as the raw material, were prepared in situ and anchored on the surface of amino-modified mesoporous silica nanoparticles (MSNs–NH2) via a microwave-assisted solvothermal reaction. The as-prepared nanohybrid (designated MSNs–CDs) not only exhibited strong and stable yellow emission but also preserved the unique features of MSNs (e.g., mesoporous structure, large specific surface area, and good biocompatibility), demonstrating a potential capability for fluorescence imaging-guided drug delivery. More interestingly, the MSNs–CDs nanohybrid was able to selectively target folate receptor-overexpressing cancer cells (e.g., HeLa), indicating that folic acid still retained its function even after undergoing the solvothermal reaction. Benefited by these excellent properties, the fluorescent MSNs–CDs nanohybrid can be employed as a fluorescence-guided nanocarrier for the targeted delivery of anticancer drugs (e.g., doxorubicin), thereby enhancing chemotherapeutic efficacy and reducing side effects. Our studies may provide a facile strategy for the fabrication of multifunctional MSN-based theranostic platforms, which is beneficial in the diagnosis and therapy of cancers in future.

    关键词: Targeted drug delivery,Fluorescence imaging,Mesoporous silica nanoparticles,Carbon dots,Chemotherapy

    更新于2025-11-14 14:48:53

  • The ablative fractional coagulation zone influences skin fluorescence intensities of topically applied test molecules-An in vitro study with fluorescence microscopy and fluorescence confocal microscopy

    摘要: Background: Ablative fractional laser (AFL) increases uptake of topically applied skin agents. The coagulation zone (CZ) surrounding vertically ablated channels may influence uptake of drugs. Objectives: To investigate impact of CZ thickness on skin fluorescence intensities (FI) of a hydrophilic molecule by means of fluorescence microscopy (FM) and fluorescence confocal microscopy (FCM). Second, to compare FI of hydrophilic and lipophilic test molecules by FCM. Study Design/Methods and Materials: Microchannels with CZ thicknesses of 0, 20, and 80 μm were generated by microneedles or AFL (10,600 nm). Channels were 700 μm deep and number of channels kept constant per skin area. After 4 hours of incubation, FI induced by sodium fluorescein (NAF, hydrophilic, logarithmic partition-coefficient (logP) = -1.52, MW = 376.26) were quantified in both CZ and surrounding skin by FM (0–1,500 μm) and FCM (0–90 μm). FI of NAF and carboxyfluorescein (CAF, lipophilic, logP = 2.9, MW = 376.32) were compared by FCM. Results: By FM, NAF-induced FI were higher in CZ than in surrounding skin (P ≤ 0.001). Highest NAF-FI were induced in skin pretreated with a thin CZ (CZ–20 μm), assessed by both FM and FCM and in particular, FI were higher than in skin pretreated with no CZ (CZ–0 μm) (FM P ≤ 0.041, FCM P < 0.012). Skin FI remained constant to a depth of 500 μm, which corresponded to approximate depth of microchannels (CZ–0 μm, CZ–20 μm, CZ–80 μm: 0–500 μm P ≥ 0.107). In accordance with FM data, FCM showed higher FI within CZ than in surrounding skin, but gradually decreased to zero at a depth of 90 μm. NAF-FI were higher than CAF-FI (P ≤ 0.036), and highest CAF-FI were induced by CZ–0 μm and CZ–20 μm compared to CZ–80 μm (P ≤ 0.009). Conclusions: The influence of the CZ thickness on skin FI differs between small hydrophilic and lipophilic test molecules. Results may have clinical relevance for laser-assisted drug delivery.

    关键词: sodium fluorescein,reflectance,carboxyfluorescein,dermatology,drug delivery,skin imaging

    更新于2025-09-23 15:23:52

  • Plasmonic Gold Nanovesicles for Biomedical Applications

    摘要: Gold nanoparticles (GNPs), with tunable optical properties, bioinertness, and surface multivalent effect, have been widely explored for biomedical applications. As one classical type of GNPs-based assemblies, plasmonic gold nanovesicles (GVs), with a hollow cavity, “solid skeleton” composed of GNPs cores and a “soft body” composed of functional polymers, have attracted considerable attention due to their tunable localized surface plasmon resonance, strong surface-enhanced Raman scattering properties, and high photothermal conversion efficiency. This review summarizes recent advances in biomedical applications for plasmonic GVs. Firstly, the synthesis methods of GVs are mainly including self-assembly and in situ gold growth methods. Secondly, the classification of GVs is described according to the morphology of GNPs cores. Thirdly, different biomedical applications of GVs are elaborated, including in vitro diagnosis, in vivo imaging, and in vivo therapy. Finally, the challenges and perspectives of GVs are discussed.

    关键词: cancer therapy,drug delivery,gold nanovesicles,biodetection,cancer imaging

    更新于2025-09-23 15:23:52

  • Vehiculización de fármacos asistida por láser

    摘要: Absorption of topical products through the epidermis is limited by the skin's barrier function. Numerous techniques and agents such as microneedling, dermabrasion, radiofrequency, and lasers have been used to increase penetration within an approach known as transdermal drug delivery. One of these techniques is laser-assisted drug delivery (LADD), which often uses ablative fractional lasers (CO2 or erbium:YAG lasers) because of their capacity to produce microscopic ablated channels. The parameters in LADD need to be adjusted to the patient, the skin condition and its location, and the drug. LADD has been used with various topical products, such as corticosteroids, photosensitizers, and immunotherapy agents (imiquimod or 5-fluorouracil) to treat numerous conditions, including scars, nonmelanoma skin cancer, and photodamage. LADD is a promising technique that enhances the absorption of topical molecules while adding the synergic effect of the laser.

    关键词: Laser-assisted drug delivery,CO2 laser,Ablative fractional laser,Hypertrophic scars,Keloid scars

    更新于2025-09-23 15:23:52

  • PEGylated doxorubicin cloaked nano-graphene oxide for dual-responsive photochemical therapy

    摘要: Graphene oxide (GO) own huge surface area and high drug loading capacity for aromatic molecules, such as doxorubicin (DOX). However, its biocompatibility is poor and it might agglomerate in physiological condition. Chemical modification of GO with hydrophilic polymer, especially PEGylation, was a common method to improve its biocompatibility. But the chemical modification of GO was complicated, and its drug loading capacity might be reduced because of the occupation of its functional groups. In this study, DOX-PEG polymers with different PEG molecular weight were synthesized to modify nano graphene oxide (NGO) to simultaneously realize the solubilization of NGO and the high loading capacity of DOX. The result showed that the drug release of NGO@DOX-PEG was pH sensitive. NIR irradiation could augment the drug release, cellular uptake, cytotoxicity and nuclear translocation of nanodrugs. Among the three kinds of nanodrugs, NGO@DOX-PEG5K was superior to others. It suggested that after conjugating with PEG, the bond between DOX-PEG and NGO was weakened, which resulted in a better drug release and treatment effect. In summary, the NIR and pH dual-responsive NGO@DOX-PEG nanodrugs were developed by noncovalent modification, and it demonstrated excellent biocompatibility and photochemical therapeutic effect, presenting a promising candidate for antitumor therapy, especially NGO@DOX-PEG5K.

    关键词: Nano-drug Delivery System,pH sensitive,Nano-Graphene Oxide,photochemical therapy,Doxorubicin

    更新于2025-09-23 15:23:52

  • A Hybrid Carrier System Based on Origami Nanostrucutures and Layer-by-Layer Microparticles

    摘要: Recent progress in DNA nanotechnology allows the fabrication of 3D structures that can be loaded with a large variety of molecular cargos and even be responsive to external stimuli. This makes the use of DNA nanostructures a promising approach for applications in nanomedicine and drug delivery. However, their low stability in the extra- and intracellular environment as well as low cellular uptake rates and release rates from endosomes into the cytoplasm hamper the efficient and targeted use of DNA nanostructures in medical applications. Here, such major obstacles are overcome by integrating DNA origami nanostructures into superordinated layer-by-layer based microparticles made from biopolymers. The modular assembly of the polymer layer allows a high-density incorporation of the DNA structures at different depth. This enables controllable protection of the DNA nanostructures over extended durations in a broad range of extra- and intracellular conditions without compromising the cell viability. Furthermore, by producing protein-complexed DNA nanostructures it is demonstrated that molecular cargo can be conveniently integrated into the developed hybrid system. This work provides the basis for a new multistage carrier system allowing for an efficient and protected transport of active agents inside responsive DNA nanostructures.

    关键词: DNA origami nanostructures,drug delivery,LbL technique,hybrid carriers

    更新于2025-09-23 15:23:52