红细胞膜封装负载姜黄素的金纳米粒子

针对姜黄素在水中溶解性差、稳定性差、难吸收、代谢快等缺点,以姜黄素、金纳米颗粒和哺乳动物红细胞膜为原料,设计开发了红细胞膜仿生纳米载药系统(Au-Cur@RBC)。抗癌药物姜黄素通过疏水作用吸附到利于封装的小尺寸金纳米颗粒表面,然后通过物理挤压的方式将载药纳米粒子包封到红细胞膜囊泡内。结果表明,制备的金纳米粒子尺寸均一度高,分散性良好,平均粒径为13.18 nm。金-姜黄素纳米颗粒中姜黄素的吸附率为86.85%,载药率为20.25%。金纳米颗粒的负载可显著提高姜黄素的稳定性,金-姜黄素纳米颗粒在水溶液中储存30 d后仍保留了52%的姜黄素。同时,暗场显微镜结果表明,红细胞膜涂覆增强了制备的Au-Cur@RBC对暗场显微镜入射光线的折射与衍射能力,从而呈现更清晰的图像。     

液晶金纳米粒子的研究进展

液晶金纳米粒子是一类非常重要的功能材料。液晶金纳米粒子不仅能自组装成一维(1D)、二维(2D)和三维(3D)有序的定向排列还能增强液晶材料的导电性。液晶金纳米粒子在非线性光学、物理化学传感器和分子识别等领域有着广泛的应用前景。综述了近年来液晶硫醇金纳米粒子的研究进展。     

金纳米粒子的应用研究进展

近年来,由于金纳米粒子独特的物理化学性质以及良好的生物相容性和生物安全性,吸引越来越多的科研工作者对其展开广泛的研究和开发。从金纳米粒子的合成方法、特性以及应用开发等方面的对金纳米粒子近年来的研究进展进行了比较详细的综述。     

植物生物质合成金纳米粒子的研究进展

植物生物质合成金纳米粒子具有无毒副作用、生物相容性好、制备简单、商业应用价值大等特点,成为近年来的研究热点.概述了植物生物质合成金纳米粒子的现状,分析了植物生物质合成金纳米粒子的可能作用机制以及植物生物质中起生物还原作用的化合物,同时还探讨了植物生物质还原合成金纳米粒子所面临的挑战.     

载姜黄素金纳米复合微粒的制备及体外释放研究

以氯金酸为原料,用水热法制备了金纳米复合微粒用作载体材料,再采用浸渍离心法负载姜黄素,得到负载姜黄素的金纳米复合微粒.采用粒度分析仪、XRD、红外、热重等方法,对金纳米复合微粒进行形貌结构表征.结果 表明,所制备的材料为表面聚集微小孔隙、平均粒径为250nm左右的微小Au复合颗粒.当料液比为1∶1、姜黄素的质量浓度为3...     

负载型纳米金催化剂的研究进展

金是一种高化学惰性金属,其纳米粒子具有独特的结构和性质,在催化、光电传感器和生物医药等领域应用广泛。研究表明,负载在金属氧化物等载体上的纳米金粒子具有很高的催化活性,特别是在CO低温催化氧化中,催化效率明显高于其他类型贵金属。纳米金催化剂的研究已经具有了相当的深度和广度,在工业催化和环境保护等领域显现出重要的发展前景和商机。     

金纳米粒子的合成和应用

金纳米粒子以它独特的光学、电学和催化性质以及在纳米级电子线路中的应用潜力,受到人们越来越多的关注.主要介绍了金纳米粒子的合成方法(模板法、湿化学法、电化学法、扫描探针微影术、光化学还原法和声化学合成法等)、成长机理和应用,展望了金纳米材料未来的研究方向和发展趋势.     

金纳米粒子的特性、制备及应用研究进展

介绍了金纳米粒子的物理化学特性,归纳了金纳米粒子的制备方法,如传统的柠檬酸钠还原法、以两相或多相体系为基础的相转移法以及分两步合成的晶种法等,并对物理辅助制备方法如在制备过程中引入超声场、激光辐射等手段进行了简单的介绍。还对金纳米粒子的应用研究进展进行了综述。     

聚苯乙烯球负载金纳米粒子的制备及其催化性能研究

研究了聚苯乙-金复合粒子在水相中催化硼氢化钠(NaBH_4)还原对硝基苯酚(p-NP)至对氨基苯酚(p-AP)的催化活性。已经制备好的AuNPs通过热力学驱动的异相凝聚法快速地负载到PS微球上。之后,PS微球负载AuNPs(PS-Au复合粒子)催化还原p-NP至p-AP的表观速率常数(kapp)为4.7×10^(-3)s(-3)s^(-1)及内在活性参数(kiap)为0.47 s(-1)及内在活性参数(kiap)为0.47 s^(-1),这要高于此前大多数的报道。这些优越的催化性能可以归功于负载的小尺寸的AuNPs以及蓝莓形貌的复合粒子催化剂。     

聚苯乙烯球负载金纳米粒子的制备及其催化性能研究

研究了聚苯乙-金复合粒子在水相中催化硼氢化钠(NaBH_4)还原对硝基苯酚(p-NP)至对氨基苯酚(p-AP)的催化活性。已经制备好的AuNPs通过热力学驱动的异相凝聚法快速地负载到PS微球上。之后,PS微球负载AuNPs(PS-Au复合粒子)催化还原p-NP至p-AP的表观速率常数(kapp)为4.7×10~(-3)s~(-1)及内在活性参数(kiap)为0.47 s~(-1),这要高于此前大多数的报道。这些优越的催化性能可以归功于负载的小尺寸的AuNPs以及蓝莓形貌的复合粒子催化剂。     

Modulatory Effects of Biosynthesized Gold Nanoparticles Conjugated with Curcumin and Paclitaxel on Tumorigenesis and Metastatic Pathways—In Vitro and In Vivo Studies

Background: Breast cancer is the most common cancer in women globally, and diagnosing it early and finding potential drug candidates against multi-drug resistant metastatic breast cancers provide the possibilities of better treatment and extending life. Methods: The current study aimed to evaluate the synergistic anti-metastatic activity of Curcumin (Cur) and Paclitaxel (Pacli) individually, the combination of Curcumin–Paclitaxel (CP), and also in conjugation with gold nanoparticles (AuNP–Curcumin (Au-C), AuNP–Paclitaxel (Au-P), and AuNP–Curcumin–Paclitaxel (Au-CP)) in various in vitro and in vivo models. Results: The results from combination treatments of CP and Au-CP demonstrated excellent synergistic cytotoxic effects in triple-negative breast cancer cell lines (MDA MB 231 and 4T1) in in vitro and in vivo mouse models. Detailed mechanistic studies were performed that reveal that the anti-cancer effects were associated with the downregulation of the expression of VEGF, CYCLIN-D1, and STAT-3 genes and upregulation of the apoptotic Caspase-9 gene. The group of mice that received CP combination therapy (with and without gold nanoparticles) showed a significant reduction in the size of tumor when compared to the Pacli alone treatment and control groups. Conclusions: Together, the results suggest that the delivery of gold conjugated Au-CP formulations may help in modulating the outcomes of chemotherapy. The present study is well supported with observations from cell-based assays, molecular and histopathological analyses.     

Design and Encapsulation of Immunomodulators onto Gold Nanoparticles in Cancer Immunotherapy

The aim of cancer immunotherapy is to reactivate autoimmune responses to combat cancer cells. To stimulate the immune system, immunomodulators, such as adjuvants, cytokines, vaccines, and checkpoint inhibitors, are extensively designed and studied. Immunomodulators have several drawbacks, such as drug instability, limited half-life, rapid drug clearance, and uncontrolled immune responses when used directly in cancer immunotherapy. Several strategies have been used to overcome these limitations. A simple and effective approach is the loading of immunomodulators onto gold-based nanoparticles (GNPs). As gold is highly biocompatible, GNPs can be administered intravenously, which aids in increasing cancer cell permeability and retention time. Various gold nanoplatforms, including nanospheres, nanoshells, nanorods, nanocages, and nanostars have been effectively used in cancer immunotherapy. Gold nanostars (GNS) are one of the most promising GNP platforms because of their unusual star-shaped geometry, which significantly increases light absorption and provides high photon-to-heat conversion efficiency due to the plasmonic effect. As a result, GNPs are a useful vehicle for delivering antigens and adjuvants that support the immune system in killing tumor cells by facilitating or activating cytotoxic T lymphocytes. This review represents recent progress in encapsulating immunomodulators into GNPs for utility in a cancer immunotherapeutic regimen.     

Gold Nanoparticles Contact with Cancer Cell: A Brief Update

The fine-tuning of the physicochemical properties of gold nanoparticles has facilitated the rapid development of multifunctional gold-based nanomaterials with diagnostic, therapeutic, and therapeutic applications. Work on gold nanoparticles is increasingly focusing on their cancer application. This review provides a summary of the main biological effects exerted by gold nanoparticles on cancer cells and highlights some critical factors involved in the interaction process (protein corona, tumor microenvironment, surface functionalization). The review also contains a brief discussion of the application of gold nanoparticles in target discovery.     

Light-Triggered Covalent Coupling of Gold Nanoparticles for Photothermal Cancer Therapy

Manipulating the cross-coupling of gold nanoparticles (AuNPs) to maximize the photothermal effect is a promising strategy for cancer therapy. Here, by taking advantage of the well-known tetrazole/alkene photoclick chemistry, we have demonstrated for the first time that small AuNPs (23 nm) decorated with both 2,5-diphenyltetrazole and methacrylic acid on their surfaces can form covalently crosslinked aggregates upon laser irradiation (λ=405 nm). In vitro studies indicated that the light-triggered assembling shifted the surface plasmon resonance of AuNPs significantly to near-infrared (NIR) regions, which as a consequence effectively enhanced the efficacy of photothermal therapy for 4T1 breast cancer cells. We thus believe that this new light-triggered cross-coupling approach might offer a valuable tool for cancer treatment.     

Curcumin Loaded Nanocarriers with Varying Charges Augmented with Electroporation Designed for Colon Cancer Therapy

(1) Background: The size and surface charge are the most significant parameters of nanocarriers that determine their efficiency and potential application. The poor cell uptake of encapsulated drugs is the main limitation in anticancer treatment. The well-defined properties of nanocarriers will enable to target specific tissue and deliver an active cargo. (2) Methods: In the current study, poly(D,L -lactide) (PLA) nanocarriers loaded with curcumin (CUR) and differing surface charge were evaluated for transport efficacy in combination with electroporation (EP) in dependence on the type of cells. The obtained CUR-loaded nanoparticles with diameters ranging from 195 to 334 nm (derived from dynamic light scattering (DLS)) were characterized by atomic force microscopy (AFM) (morphology and shape) and Doppler electrophoresis (ζ-potential) as well as UV-vis spectroscopy (CUR encapsulation efficiency (about 90%) and photobleaching rate). The drug delivery properties of the obtained PLA nanocarriers enhanced by electroporation were assessed in human colon cancer cells (LoVo), excitable normal rat muscle cells (L6), and free of voltage-gated ion channels cells (CHO-K1). CLSM studies, viability, and ROS release were performed to determine the biological effects of nanocarriers. (3) Results: The highest photodynamic activity indicated anionic nanocarriers (1a) stabilized by C₁₂(COONa)₂ surfactant. Nanocarriers were cytotoxic for LoVo cells and less cytotoxic for normal cells. ROS release increased in cancer cells with the increasing electric field intensity, irradiation, and time after EP. Muscle L6 cells were less sensitive to electric pulses. (4) Conclusions: EP stimulation for CUR-PLA nanocarriers transport was considered to improve the regulated and more effective delivery of nanosystems differing in surface charge.     

Oxidative Damage to Mitochondria Enhanced by Ionising Radiation and Gold Nanoparticles in Cancer Cells

Gold nanoparticles (AuNP) can increase the efficacy of radiation therapy by sensitising tumor cells to radiation damage. When used in combination with radiation, AuNPs enhance the rate of cell killing; hence, they may be of great value in radiotherapy. This study assessed the effects of radiation and AuNPs on mitochondrial reactive oxygen species (ROS) generation in cancer cells as an adjunct therapeutic target in addition to the DNA of the cell. Mitochondria are considered one of the primary sources of cellular ROS. High levels of ROS can result in an intracellular state of oxidative stress, leading to permanent cell damage. In this study, human melanoma and prostate cancer cell lines, with and without AuNPs, were irradiated with 6-Megavolt X-rays at doses of 0–8 Gy. Indicators of mitochondrial stress were quantified using two techniques, and were found to be significantly increased by the inclusion of AuNPs in both cell lines. Radiobiological damage to mitochondria was quantified via increased ROS activity. The ROS production by mitochondria in cells was enhanced by the inclusion of AuNPs, peaking at ~4 Gy and then decreasing at higher doses. This increased mitochondrial stress may lead to more effectively kill of AuNP-treated cells, further enhancing the applicability of functionally-guided nanoparticles.     

Dose Rate Effects on the Selective Radiosensitization of Prostate Cells by GRPR-Targeted Gold Nanoparticles

For a while, gold nanoparticles (AuNPs) have been recognized as potential radiosensitizers in cancer radiation therapy, mainly due to their physical properties, making them appealing for medical applications. Nevertheless, the performance of AuNPs as radiosensitizers still raises important questions that need further investigation. Searching for selective prostate (PCa) radiosensitizing agents, we studied the radiosensitization capability of the target-specific AuNP-BBN in cancer versus non-cancerous prostate cells, including the evaluation of dose rate effects in comparison with non-targeted counterparts (AuNP-TDOTA). PCa cells were found to exhibit increased AuNP uptake when compared to non-tumoral ones, leading to a significant loss of cellular proliferation ability and complex DNA damage, evidenced by the occurrence of multiple micronucleus per binucleated cell, in the case of PC3 cells irradiated with 2 Gy of γ-rays, after incubation with AuNP-BBN. Remarkably, the treatment of the PC3 cells with AuNP-BBN led to a much stronger influence of the dose rate on the cellular survival upon γ-photon irradiation, as well as on their genomic instability. Overall, AuNP-BBN emerged in this study as a very promising nanotool for the efficient and selective radiosensitization of human prostate cancer PC3 cells, therefore deserving further preclinical evaluation in adequate animal models for prostate cancer radiotherapy.     

Electrochemical Determination of Food Preservative Nitrite with Gold Nanoparticles/p-Aminothiophenol-Modified Gold Electrode

Due to the negative impact of nitrate and nitrite on human health, their presence exceeding acceptable levels is not desired in foodstuffs. Thus, nitrite determination at low concentrations is a major challenge in electroanalytical chemistry, which can be achieved by fast, cheap, and safe electrochemical sensors. In this work, the working electrode (Au) was functionalized with p-aminothiophenol (p-ATP) and modified with gold nanoparticles (Au-NPs) to manufacture the final (Au/p-ATP-Au_nano) electrode in a two-step procedure. In the first step, p-ATP was electropolymerized on the electrode surface to obtain a polyaminothiophenol (PATP) coating. In the second step, Au/p-ATP-Au_nano working electrode was prepared by coating the surface with the use of HAuCl₄ solution and cyclic voltammetry. Determination of aqueous nitrite samples was performed with the proposed electrode (Au/p-ATP-Au_nano) using square wave voltammetry (SWV) in pH 4 buffer medium. Characteristic peak potential of nitrite samples was 0.76 V, and linear calibration curves of current intensity versus concentration was linear in the range of 0.5–50 mg·L⁻¹ nitrite with a limit of detection (LOD) of 0.12 mg·L⁻¹. Alternatively, nitrite in sausage samples could be colorimetrically determined with high sensitivity by means of p-ATP‒modified gold nanoparticles (AuNPs) and naphthylethylene diamine as coupling agents for azo-dye formation due to enhanced charge-transfer interactions with the AuNPs surface. The slopes of the calibration lines in pure NO₂⁻ solution and in sausage sample solution, to which different concentrations of NO₂⁻ standards were added, were not significantly different from each other, confirming the robustness and interference tolerance of the method. The proposed voltammetric sensing method was validated against the colorimetric nanosensing method in sausage samples.     

Shuttling Gold Nanoparticles into Tumoral Cells with an Amphipathic Proline‐Rich Peptide

Golden bullets : The amphipathic proline‐rich cell‐penetrating peptide sweet arrow peptide (SAP) is able to transport 12 nm gold nanoparticles efficiently into HeLa cells, as observed by three microscopy techniques: transmission electron microscopy (TEM), confocal laser scanning microscopy (CLSM) and transmission X‐ray microscopy (TXM). Multiconjugation to such nanoparticles may provide a convenient method for unifying the key drug properties of high activity, capacity to home onto targets and delivery to therapeutic places of action.