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oe1(光电查) - 科学论文

17 条数据
?? 中文(中国)
  • Photo-Controlled Release of Metal Ions Using Triazoline-Containing Amphiphilic Copolymers

    摘要: Photo-controlled release that shows quick response and high spatial/temporal accuracy has become attractive given its potential applications for biomedicines. A few metal complexes are known for detoxification, sterilization, diagnosis and treatment of diseases; but, the encapsulation and control release of those metal ions using polymer micelles are challenging. We report an interesting photo-controlled release of metal ions via photo-responsible triazoline-containing amphiphilic polymers. Amphiphilic random copolymers of glycidyl methacrylate and oligo(ethylene oxide) methyl ether methacrylate were prepared through free radical copolymerization. The glycidyl pendants were converted to azide, followed by a 1,3-dipolar cycloaddition reaction to form triazoline with norbornene. The resulting random copolymers containing triazoline formed micelles with a critical micellar concentration (CMC) of 7.68×10-3 mg/mL. The triazoline moieties could coordinate to transition metal ions, e.g. Co2+, thus to encapsulate the metal ions to the core of micelles. Photo-induced denitrogenation of triazoline was able to disrupt the coordination of Co2+ and triazoline, therefore leading to the release of Co2+. Solution viscosity, UV-vis/NMR spectroscopy and TEM were used to show that the coordination and release of Co2+ ions were successful upon exposure to light. The photo-controlled release profile was found to be linearly dependent on the irradiation time, which is potentially useful for the delivery of essential ions in vivo.

    关键词: Light responsive,Amphiphilic polymers,Micelles,Triazoline,Photo-controlled release

    更新于2025-11-19 16:46:39

  • Influence of water-controlled release process on the physical and chemical property of nanosize TiO <sub/>2</sub> particles

    摘要: The water-controlled release process (WCRP) was utilized for the synthesis of TiO2 photocatalyst. The effect of alkylated esterified WCRP system on the morphology, specific surface area (SSA) and photocatalytic activity of TiO2 were studied systematically. By changing the structure of alcohol and acid involved in the esterification reaction, we found that the SSA and photocatalytic activity of TiO2 obtained in an ethanol/acetic acid reaction mixture showed the best results. Interestingly, the TiO2 obtained in t-butanol/acetic acid contains both the anatase and rutile phase, while the other systems only possessed anatase phases. The conditions of ethanol and acetic acid esterification were optimized and the experimental results showed that the SSA of nano-TiO2 was improved by shorting the reaction time or adding an organic solvent, which can form an azeotrope with water, but no effect on the photocatalytic activity could be observed. The reaction mechanism of esterified WCRP system was furthermore studied by NMR spectroscopy, showing three kinds of reaction, namely esterification, etherification and hydrolysis.

    关键词: water-controlled release process(WCRP),p-toluenesulfonic acid,esterification,photocatalytic,titania

    更新于2025-11-14 17:04:02

  • Mesoporous silica-coated gold nanoframes as drug delivery system for remotely controllable chemo-photothermal combination therapy

    摘要: Tumor cells experience higher chemotherapy stress under condition of elevated temperature. As a result, developing novel nanoagents that integrates chemotherapy and thermotherapy holds great promise in biomedicine. Herein, utilizing spatially confined galvanic replacement method, we fabricated a yolk-shell Au@mSiO2 nanoframes with Au NPs and mesoporous silica as yolk and shell, respectively, to sever as an excellent drug nanocarrier with effective photothermal conversion efficiency. Taking full advantage of the high temperature response of the Au@mSiO2 nanoframes, the phase change material 1-tetradecanol (TD) was creatively employed as gatekeepers, intelligently controlling the release of loaded agents. Then, the actively targeted Alanine-Alanine-Asparagine, legumain-recognizable oligopeptides was decorated on the surface of the prepared nanoframes. Upon exposure to near-infrared light, the GC-PtAu@mSiO2-TD nanoframes not only exhibited a high localized temperature response, but also triggered the quick release of loaded cargos, and thus improved the chemotherapeutic efficacy. The in vitro cytotoxicity studies indicated the remarkable synergistic effects. Meanwhile, the laser confocal studies and flow cytometry showed the oligopeptides facilitated the intracellular uptake of GC-PtAu@mSiO2-TD nanoframes in MGC-803 cells. Our study highlighted the great potential of the GC-PtAu@mSiO2-TD nanoframes in drug delivery and the combination of chemotherapy and photothermal therapy.

    关键词: Cisplatin,Mesoporous silica-gold nanoframes,Phase-change materials,Photothermal therapy,Controlled release

    更新于2025-09-23 15:23:52

  • NIR Light- and pH-Responsive Graphene Oxide Hybrid Cyclodextrin-Based Supramolecular Hydrogels

    摘要: Here a novel triple-responsive graphene oxide hybrid supramolecular hydrogel based on the electrostatic self-assembly between graphene oxide and a quaternized polymer and the host-guest inclusion between α-cyclodextrins and polyethylene glycol monomethylether (mPEG) was constructed. The quaternized polymer was synthesized by quaternization between pH sensitive poly(N,N-dimethylaminoethyl methacrylate) and bromine end-capped polyethylene glycol monomethylether. The supramolecular hydrogels prepared from the host-guest inclusion of polyethylene glycol monomethylether and α-cyclodextrins would turn into a mobile sol phase when the temperature increased above a certain temperature (Tgel-sol). Graphene oxide sheets not only acted as a core material to provide additional cross-linking, but also absorbed NIR light and converted NIR light into heat to trigger the gel-sol transition. The constructed graphene oxide hybrid cyclodextrin-based supramolecular hydrogels could respond to NIR light, temperature and pH, which could be beneficial for controlled release of cargoes and would hold great promise in the field of delivery systems.

    关键词: graphene oxide,self-assembly,cyclodextrin,hydrogel,controlled release

    更新于2025-09-23 15:23:52

  • Pharmacokinetic Simulations of Intravitreal Biologicals: Aspects of Drug Delivery to the Posterior and Anterior Segments

    摘要: Biologicals are important ocular drugs that are be delivered using monthly and bimonthly intravitreal injections to treat retinal diseases, such as age-related macular degeneration. Long acting delivery systems are needed for prolongation of their dosing interval. Intravitreal biologicals are eliminated from the eye via the aqueous humor outflow. Thus, the anterior and posterior segments are exposed to the drug. We utilized a kinetic simulation model to estimate protein drug concentrations in the vitreous and aqueous humor after bolus injection and controlled release administration to the vitreous. The simulations predicted accurately the experimental levels of 5 biologicals in the vitreous and aqueous humor. The good match between the simulations and experimental data demonstrated almost complete anterior segment bioavailability, and major dose sparing with ocular controlled release systems. Overall, the model is a useful tool in the design of intraocular delivery of biologicals.

    关键词: aflibercept,ocular drug delivery,ranibizumab,intravitreal injection,controlled release,bevacizumab

    更新于2025-09-23 15:22:29

  • Multifunctional nanoplatforms for photoacoustic imaging-guided combined therapy enhanced by CO induced ferroptosis

    摘要: A multifunctional CO/thermo/chemotherapy nanoplatform is here reported, which is composed of mesoporous carbon nanoparticles (MCN) as near-infrared (NIR)-responsive drug carrier, doxorubicin (DOX) as chemotherapeutic drug and triiron dodecacarbonyl (FeCO) as thermosensitive CO prodrug. The nanoplatform could absorb near-infrared (NIR) light and convert it into ample heat to trigger CO release and could also release DOX in the acidic tumor microenvironment. More importantly, the generated CO molecules successfully increase cancer cell sensitivity to chemotherapeutics by the ferroptosis pathway. Subsequently, under the guidance of photoacoustic imaging, the FeCO-DOX@MCN nanoplatform demonstrates high treatment efficacies in vitro and in vivo by combination of chemotherapy, photothermal therapy and gas therapy. This multifunctional platform with excellent antitumor efficacy has great potential in precision cancer therapy.

    关键词: Mesoporous materials,Ferroptosis,Controlled release,Photothermal therapy,Carbon monoxide

    更新于2025-09-23 15:22:29

  • Development of a photon induced drug-delivery implant coating

    摘要: A thin surface coating intended for medical devices such as implants where local drug release is enabled using near infrared light (NIR) as an external stimulus has been developed. The delivery system consists of a thin Poly (N-isopropylacrylamide)-co-acrylamide (PNIPAAm-AAm) polymer layer with incorporated gold nanorods (GNRs). The aspect ratio of the GNRs were chosen to absorb NIR light, thus ?tting the biological window of low tissue absorption, to locally heat the polymeric layer to initiate a drug release. Hence, controlled drug delivery from a surface within tissue orchestrated from outside the body is achievable. Composition of the PNIPAAm-AAm co-polymer was systematically varied to ?nd a suitable phase transition temperature for in vivo applications. Di?erential scanning calorimetry (DSC) analysis showed that PNIPAAm-AAm containing 10% acrylamide had an appropriate phase transition temperature of 42 °C. As visualized by scanning electron microscopy (SEM), the surface coating consisted of 200 nm uniform polymer layer. Quartz crystal microbalance with dissipation monitoring (QCM-D) analysis coupled with in situ NIR irradiation demonstrated a dramatic shift in frequency that was attributed to mass being released from the surface upon irradiation. This mass release correlated well with the drug release pro?le as determined using UV/VIS spectroscopy with phenol as a model drug. In addition, proof-of-concept of the drug-delivery system was demonstrated by releasing the antibiotic vancomycin to eradicate Staphylococcus epidermidis bacteria in culture.

    关键词: Thermo-sensitive,Drug delivery,Controlled release,Poly(N-isopropylacrylamide),Implant coating

    更新于2025-09-23 15:22:29

  • GNRs/PPy/m-SiO2 Core/Shell Hybrids as Drug Nanocarriers for Efficient Chemo-Photothermal Therapy

    摘要: Combination therapy as a novel strategy with the combination of photothermal therapy and chemotherapy (photothermal-chemotherapy) has aroused the tremendously increasing interest owing to the synergistic therapeutic effect on destroying cancer cells since that the hyperthermia generated from photothermal therapy can promote drug delivery into tumors, which would highly increase therapeutic efficacy as compared to those sole treatments. Herein, we fabricated a novel nanomaterial-based carrier composed of GNRs, polypyrrole (PPy) and mesoporous silica to form GNRs/PPy/m-SiO2 core/shell hybrids. After loading the anticancer drug of doxorubicin (DOX), the photothermal effect and the drug-release behavior of GNRs/PPy@m-SiO2-DOX hybrids were investigated. The in vitro and in vivo near-infrared (NIR) photothermal-chemotherapy were also revealed. The results indicated the NIR-induced photothermal effect was beneficial to promote the release of the drug. In addition, combination therapy demonstrated the enhanced synergistic efficacy and excellent treatment efficacy for cancer therapy.

    关键词: drug-controlled release,gold nanorod,mesoporous silica,combination therapy,photothermal,conducting polymer

    更新于2025-09-23 15:21:21

  • Drug-releasing Biopolymeric Structures Manufactured via Stereolithography

    摘要: Additive manufacturing (AM) techniques, such as stereolithography (SLA), enable the preparation of designed complex structures. AM has gained interest especially in the tissue engineering field due to the possibility to manufacture patient specific implants. However, AM could be useful also in controlled drug release applications, since the size and shape of the device, pore architecture and surface to volume ratio can be accurately designed. In this study, SLA was used to prepare polycaprolactone scaffold structures containing the model drug lidocaine. The release of lidocaine was studied and the influence of porosity and surface to volume ratio of structures to the drug release was analyzed. Porous samples released lidocaine faster compared to solid ones, whereas the degree of porosity and surface to volume ratio did not have a clear effect on the drug release profile.

    关键词: drug delivery,stereolithography,additive manufacturing,drug release,lidocaine,scaffold,controlled release,polycaprolactone

    更新于2025-09-23 15:21:01

  • Surface Modification of Liposomes Using IR700 Enables Efficient Controlled Contents Release Triggered by Near-IR Light

    摘要: Stimuli-responsive liposomes are promising drug carriers for cancer treatment because they enable controlled drug release and the maintenance of desired drug concentrations in tumor tissue. In particular, near-IR (NIR) light is a useful stimulus for triggering drug release from liposomes based on its advantages such as deep tissue penetration and safety. Previously, we found that a silicon phthalocyanine derivative, IR700, conjugated to antibodies, can induce the rupture of the cell membrane following irradiation by NIR light. Based on this finding, we constructed IR700-modified liposomes (IR700 liposomes) and evaluated their drug release properties triggered by NIR light. IR700 liposomes released substantial amounts of encapsulated calcein following irradiation by NIR light. Drug release was substantially suppressed by the addition of sodium azide, suggesting that liposomal membrane permeabilization was mediated by singlet oxygen generated from IR700. Moreover, calcein release from IR700 liposomes triggered by NIR light was promoted under conditions of deoxygenation and the presence of electron donors. Thus, membrane disruption should be induced by the physical change of IR700 from highly hydrophilic to hydrophobic as we previously described, although singlet oxygen can cause a certain level of membrane disruption under normoxia. We also observed that doxorubicin-encapsulated IR700 liposomes exhibited significant cytotoxic effects against CT-26 murine colon carcinoma cells following NIR light exposure. These results indicate that IR700 liposomes can efficiently release anti-cancer drugs following NIR light irradiation even under hypoxic conditions and, therefore, they would be useful for cancer treatment.

    关键词: controlled release,IR700,liposome,near-IR light

    更新于2025-09-23 15:21:01