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oe1(光电查) - 科学论文

16 条数据
?? 中文(中国)
  • Plasmonic Colorimetric Biosensor for Visual Detection of Telomerase Activity Based on Horseradish Peroxidase-Encapsulated Liposomes and Etching of Au Nanobipyramids

    摘要: Telomerase aberrant activation is a critical feature in the vast majority of cancers. To visualize telomerase expression level in tumor cells, we developed a plasmonic colorimetric sensor for highly sensitive detection of telomerase activity by integrating an excellent etching substrate Au nanobipyramids (Au NBPs) with a liposome-based signal amplification strategy. Upon telomerase-triggered extension, the telomerase activity was converted into the amount of the attached horseradish peroxidase-encapsulated liposomes (HRP-Ls) on the surfaces of magnetic beads. Afterwards, HRP was liberated from the liposomes following the addition of H2O2-3,3′,5,5′-tetramethylbenzidine sulfate (TMB) substrate, and then the oxidation reaction between H2O2 and TMB was initiated to form TMB2+. The morphological evolution of Au NBPs relied on the TMB2+-mediated etching reaction, which gave rise to tremendous localized surface plasmon resonance (LSPR) responses and concomitant tonality transitions. Benefiting from cascaded signal amplification capacity of HRP-Ls and the intriguing optical properties of Au NBPs, an impressive sensitivity toward telomerase was obtained with detection limits equivalent to 1 HeLa cell for LSPR peak measurement and a visual detection limit of 20 HeLa cells. Furthermore, a facile and portable kit was fabricated for visual evaluation of telomerase activity in different cell lines.

    关键词: Plasmonic colorimetry,Au nanobipyramids,Telomerase,Liposome-based amplification,Multicolor visual detection

    更新于2025-11-14 17:04:02

  • PEG-coated vesicles from Pluronic/lipid mixtures for the carrying of photoactive erythrosine derivatives

    摘要: Liposomes are very attractive membrane models and excellent drug delivery systems. Concerning their drug delivery aspects, the mixing liposomes with biocompatible copolymers allows for stability and the incorporation of several drugs. We developed PEG coated vesicles from the mixture of DPPC and F127 Pluronic copolymer to obtain long-circulating nanoparticles (mixed vesicles). We employed an innovative process previously developed by us: a small amount of F127 mixed in DPPC, thin film preparation, followed by hydration (lipids plus F127) using a bath sonicator cleaner type, forming unilamellar spherical vesicles with diameter ~100 nm. The formed PEG coated vesicles were incorporated with the xanthene dye Erythrosine B (ERY), and its ester derivatives as photosensitizers (PS) for photodynamic proposes. The F127/DPPC mixed vesicles promoted a higher PS incorporation, and with better thermal and kinetic stability, at least 60 days, when compared to conventional DPPC liposome. The binding constant and quenching analysis revealed that with a higher PS hydrophobicity, PS affinity increases toward the nanoparticle and results in a deeper PS location inside the lipid bilayer. An increment in the fluorescence quantum yield was observed, while the PS singlet oxygen generations remained high. Dialysis studies demonstrated that PS were released based on their hydrophobicity. Permeation analysis showed that all PS can reach the deeper regions of the skin. The Decyl Ester derivative/nanoparticle exhibited high photoactivity against Caco-2 cancer cells (in vitro studies). The PEG coated from F127/DPPC mixed vesicles are very promising nanocarriers for erythrosine and its derivatives.

    关键词: Stealth liposome,Pluronics,Mixed vesicles,Photodynamic,Xanthenes

    更新于2025-09-23 15:23:52

  • Methylene-Blue-Encapsulated Liposomes as Photodynamic Therapy Nano Agents for Breast Cancer Cells

    摘要: Methylene blue (MB) is a widely used dye and photodynamic therapy (PDT) agent that can produce reactive oxygen species (ROS) after light exposure, triggering apoptosis. However, it is hard for the dye to penetrate through the cell membrane, leading to poor cellular uptake; thus, drug carriers, which could enhance the cellular uptake, are a suitable solution. In addition, the defective vessels resulting from fast vessel outgrowth leads to an enhanced permeability and retention (EPR) effect, which gives nanoscale drug carriers a promising potential. In this study, we applied poly(12-(methacryloyloxy)dodecyl phosphorylcholine), a zwitterionic polymer-lipid, to self-assemble into liposomes and encapsulate MB (MB-liposome). Its properties of high stability and fast intracellular uptake were confirmed, and the higher in vitro ROS generation ability of MB-liposomes than that of free MB was also verified. For in vivo tests, we examined the toxicity in mice via tail vein injection. With the features found, MB-liposome has the potential of being an effective PDT nano agent for cancer therapy.

    关键词: methylene blue,zwitterion,liposome,photodynamic therapy,breast cancer cell

    更新于2025-09-23 15:23:52

  • Photodynamic therapy of cancer with liposomal photosensitizers

    摘要: The photodynamic reaction involves the light-induced generation of an excited state in a photosensitizer molecule (PS), which then results in the formation of reactive oxygen species in the presence of oxygen, or a direct modification of a cellular molecule. Most PSs are porphyrinoids, which are highly lipophilic, and are administered usually in liposomes to facilitate their effective delivery to target cells. The currently available liposomal formulations are Visudyne R(cid:2) and Fospeg R(cid:2). Novel PSs were developed and tested for their photodynamic activity against cancer cells. Several compounds were highly phototoxic to oral cancer cells both in free and liposome-encapsulated form, with nanomolar IC50 values. The lowest IC50s (7–13 nM) were obtained with a PS encapsulated in cationic liposomes.

    关键词: photosensitizer,liposome,photodynamic therapy,cytotoxicity,porphyrazine

    更新于2025-09-23 15:21:21

  • 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

  • Novel ?2-1,3-D-glucan porous microcapsule enveloped folate-functionalized liposomes as a Trojan horse for facilitated oral tumor-targeted co-delivery of chemotherapeutic drugs and quantum dot

    摘要: In this study, a new type of β-1,3-D-glucan porous microcapsule (GPM)-enveloped and folate conjugated chitosan-functional liposome (FCL), FCL@GPM, was developed for the potential oral co-delivery of chemotherapeutic drugs and quantum dots (QDs) with facilitated drug absorption and antitumor efficacy. In this dual-particulate system, multiple FCLs serve as the cores for effective loading, folate-mediated tumor-targeting, facilitated intracellular accumulation, and pH-responsive controlled release of chemotherapeutic agents, while a GPM acts as the shell for affording macrophage-mediated tumor selectivity. Gefitinib (GEF) was selected as a chemotherapeutic agent, while acid degradable ZnO QDs were selected due to its dual role both as an anticancer agent for synergistic chemotherapy and as a fluorescent probe for potential cancer cellular imaging. The GEF and ZnO QDs co-loaded FCL@GPMs (GEF/ZnO-FCL@GPMs) have a prolonged release manner with limited release before uptake by intestinal cells. Furthermore, the Peyer’s patches uptake, macrophages uptake, cytotoxicity, and biodistribution of FCL@GPMs were tested. In addition, GEF and ZnO QDs co-loaded FCLs (GEF/ZnO-FCLs) not only have a tumor acidity responsive release property, but also induce a superior cytotoxicity on cancer cells as compared to GEF. Moreover, a 1.75-fold increase in the bioavailability of GEF delivered from GEF/ZnO-FCL@GPMs as compared to its trademarked drug (Iressa?). As a result, GEF/ZnO-FCL@GPMs exerted a superior antitumor efficacy (1.47-fold) as compared to its trademarked drug in mice. Considered together, the developed FCL@GPMs, combining the unique physicochemical and biological benefits of FCLs and GPMs, possess a great potential as an efficient delivery system for the co-delivery of chemotherapeutic agents and quantum dots.

    关键词: chemotherapeutic drugs,pH-responsive controlled release,tumor-targeting,oral co-delivery,macrophage-mediated tumor selectivity,β-1,3-D-glucan porous microcapsule,folate conjugated chitosan-functional liposome,quantum dots

    更新于2025-09-23 15:19:57

  • SLIM microscopy allows for visualization of DNA-containing liposomes designed for sperm-mediated gene transfer in cattle

    摘要: Naked DNA has been shown to bind naturally to the sperm, a method called sperm-mediated gene transfer (SMGT). Based on these observations, we examined the efficiency of exogenous DNA binding to sperm using liposomes. In this experiment, we analyzed methods to select frozen-thawed bovine sperm, and evaluated the binding of exogenous DNA to those sperm. To determine the optimal selection method, we used Computer-Assisted Sperm Analysis (CASA). Percoll or Swim-Up were used to select sperm, followed by incubation up to 3 h with the liposome-DNA complexes. The samples were collected after 1 h and after 3 h. We used enhanced green fluorescent protein (eGFP) in combination with the liposomes as a marker for exogenous DNA binding. Five treatments per selection method were analyzed: (1) no incubation, no liposomes and no DNA, (2) incubation with no liposomes and no DNA, (3) incubation with liposomes and no DNA, (4) incubation with liposomes and 1 μg of DNA and (5) incubation with liposomes and 10 μg of DNA. The CASA results for total motility and rapid motility were statistically significant (P < 0.01) between the control and the other treatments in the Percoll group as opposed to Swim-Up. Swim-Up was therefore chosen as the optimal selection method. In order to determine if the liposome-DNA complex had bound to sperm, real time PCR was used to detect GFP DNA and images of the sperm were analyzed using the Spatial Light Interference Microscopy (SLIM). SLIM confirmed the presence of liposomes on the sperm head and tail.

    关键词: GFP,Sperm,Liposome,SLIM,Microscopy,Sperm-mediated gene transfer

    更新于2025-09-23 15:19:57

  • Rational design of nanoptodes architecture – Towards multifunctional sensors

    摘要: Liposome type nano-optodes are reported. Probe architecture allows tailored – yet spontaneous – positioning of the reporter dye with chromophore group facing the sample solution. As a result the emission signal – related to competition between analyte cations and hydrogen ions, ultimately leading to deprotonation of chromoionophore and emission increase – can be read instantly after contact of the sensor with sample but also allows observation of optical signal in unique for these sensors days’ time scale, without loss of intensity. Possibility of optode signal observation in days’ time scale allows exploration of solvatochromic properties of applied chromoionophore group and estimation of sensor sample contact time as minute change in the position of chromophore group emission maximum.

    关键词: Liposome,Fluorimetry,Optode,Time,Nanosensor,Concentration

    更新于2025-09-19 17:15:36

  • The THE INFLUENCE OF CHLORPROMAZINE HYDROCHLORIDE ON THE SIZE OF SMALL UNILAMELLAR DIMYROSTYLPHOSPHATIDYLCHOLINE LIPOSOMES AS REVEALED BY LIGHT SCATTERING PHOTOMETRY

    摘要: This study aims to investigate the possible influence of the model, cationic, surface-active solute chlorpromazine hydrochloride (CPZ-HCl) on the size of small unilamellar dimyristoyl phosphatidylcholine (DMPC) liposomes as a function of temperature and CPZ-HCl concentration, below and above the critical micelle concentration (CMC). Small unilamellar DMPC liposomes were prepared by dissolving DMPC in chloroform and the solvent was rota-evaporated in a water bath adjusted at 40 °C. The lipid film was then dispersed in 0.1 M KCl solution adjusted at pH 6.2 to form large multilamellar liposomes which are then sonicated and fractionated via Sepharose 2B-Cl gel. The elution profile was followed spectrophotometrically at λ 260 nm. Combined fractions from the trailing edge of the included peak which is due to small unilamellar liposomes, were used as a source throughout this study. The SOFICA light scattering photometer (Model 42000) was used to determine the weight average liposomes weight (Lw) of small unilamellar DMPC liposomes. The Lw was determined in the absence and presence of CPZ-HCl both above and below the CMC over the temperature range of 25 °C to 40 °C. The Lw was observed to increase linearly in the absence and presence of CPZ-HCl. The Lw was observed to increase linearly in the absence of CPZ-HCl, from 1.88×10^6 +0.03 g/mol at 40 °C. Similarly, the Lw was observed to increase linearly in the present of CPZ-HCl, for example at 18 mmol drug concentration, the Lw increases from 11×10^6 +0.04 g/mol at 25 °C to 13.75×10^6 +0.03 g/mol at 40 °C. When the data are presented as a function of CPZ-HCl concentration, a gradual increase in Lw was observed below the CMC. Little increase in Lw however, was observed at post-micellar concentrations of 14 mmol and 18 mmol. The increase in Lw in the presence of the model cationic, surface-active solute CPZ-HCl as a function of concentration and temperature indicate that CPZ-HCl interacts with small unilamellar DMPC liposomes at concentrations below and above the CMC.

    关键词: Temperature,CPZ-HCl,DMPC liposome,CMC

    更新于2025-09-19 17:13:59

  • Quercetin encapsulated biodegradable plasmonic nanoparticles for photothermal therapy of hepatocellular carcinoma cells

    摘要: Photothermal therapy (PTT) is emerging as an effective treatment modality for cancer due to its non-invasive nature. However, the pro-inflammatory necrotic cell death during PTT limits its successful clinical application. Here, we have developed quercetin (QE) loaded biodegradable plasmonic nanoparticles that can specifically induce apoptosis in cancer cells after PTT. We have synthesized gold-coated liposome (LiposAu) and QE loaded gold-coated liposome (QE-LiposAu) nanoparticles by in situ reduction of chloroauric acid with ascorbic acid in the presence of bare liposomes (Lipos) or QE loaded liposomes (QE-Lipos), respectively. The gold coating was confirmed by transmission electron microscopic analysis, dynamic light scattering, and zeta potential measurements. LiposAu and QE-LiposAu nanoparticles showed a similar level of temperature rise upon 750 nm near-infrared (NIR) laser (650 mW, 3 W cm-2) irradiation. The photothermal conversion efficiency of QE-LiposAu nanoparticles was determined to be ~75%. The efficacy of PTT was found to be dependent on the internalization efficiency of LiposAu nanoparticles in cancer cells. Importantly, QE-LiposAu nanoparticles showed increased PTT efficacy over LiposAu nanoparticles in hepatocellular carcinoma cells (Huh-7). Moreover, QE-LiposAu nanoparticles induced apoptosis-mediated cell death after the PTT, and the extent of apoptosis was significantly higher than the LiposAu nanoparticles in Huh-7 cells. Further, QE-LiposAu nanoparticles-mediated PTT depolymerized microtubules network, suppressed Hsp70 expression, and caused DNA damage. QE-LiposAu nanoparticles were also found to be hemocompatible. The results together suggested that biodegradable QE-LiposAu nanoparticles are promising photothermal agents for cancer therapy.

    关键词: heat shock protein,liposome,microtubule,apoptosis,gold nanoparticles,DNA damage,Photothermal therapy

    更新于2025-09-12 10:27:22