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1.
In the present study, we developed a novel colorimetric strategy for the visible rapid detection of the influenza virus based on the unique optical properties of gold nanorods. Specifically, lipoic acid-modified Oseltamivir (OS), which is a strong neuraminidase inhibitor and used as the first-line drug in the treatment of influenza, was synthesized and further attached to the surface of gold nanorods (OS-LA-GNRs). The absorption band and density of OS-LA-GNRs were changed with the decreasing distance between the nanoparticles induced by the target-specific aggregation via strong neuraminidase–OS binding. All of these could be visible with the naked eyes and measured by UV-visible spectrophotometry. The results showed that our system had a comparable limit of detection (LOD) to the commercial colloidal gold stripes, making it feasible for wide diagnostic applications. 相似文献
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Assessment of the Biological Activities of Egyptian Purslane (Portulaca oleracea) Extract after Incorporating Metal Nanoparticles,in Vitro and in Vivo Study 下载免费PDF全文
Wael Mahmoud AboulthanaNagwa Ibrahim OmarEnas Ahmed HasanKawkab A. AhmedAhmed Mahmoud Youssef 《Asian Pacific journal of cancer prevention》2022,23(1):287-310
Objective: Egyptian Purslane (Portulaca oleracea) is rich in omega-3 fatty acids and a wide range of vitamins and phyto-constituents that were absorbed slowly due to their high molecular weights. Therefore, this study was designed to accelerate the absorption of these phyto-constituents and hence increase their bioavailability by incorporating silver (Ag-NPs) and zinc oxide nanoparticles (ZnO-NPs) due to their impressive properties. Methods: The major phyto-constituents and different biological activities were quantified in aqueous extract before and after incorporating metal nanoparticles (M-NPs). The efficiency of ZnO-P. nano-extract was studied on cell cycle and apoptosis of human hepatocellular carcinoma (HEPG-2) cells. Then, both Ag- and ZnO-P. nano-extracts were studied against hepatic fibrosis induced by thioacetamide (TAA) in rats through undergoing different hematological and biochemical measurements in addition to the histopathological examination in hepatic tissues compared to the extract itself. Results: The ZnO-P. nano-extract showed significantly (P<0.05) higher antioxidant and scavenging activity due to the existence of higher total polyphenolic content. Also, it exhibited a significantly (P<0.05) higher inhibitory effect on acetyl cholinesterase (AChE) activity and higher cytotoxic activity against HEPG-2 cells. Therefore, ZnO-P. nano-extract was studied against the cell cycle and apoptosis of HEPG-2 cells compared to the extract itself. It was found that ZnO-P. nano-extract was safer than Ag-P. nano-extract. Both Ag- and ZnO- P. nano-extracts were studied against the hepatic fibrosis induced by thioacetamide (TAA) compared to the native extract. It was noticed that ZnO-P. nano-extract exhibited an ameliorative effect against hepatic fibrosis by decreasing levels of inflammatory and fibrotic markers significantly (P<0.05) more than Ag-P. nano-extract. Furthermore, it improved the antioxidant status of the hepatic tissue in addition to restoring the histopathological architecture of liver tissue. Conclusion: ZnO-P. nano-extract showed higher in vitro and in vivo biological activities than Ag-P. nano-extract and native P. extract itself. 相似文献
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目的:优化穿心莲内酯甲氧基聚乙二醇-聚乳酸-羟基乙酸[methoxy poly(ethylene glycol)-poly(lactic-co-glycolic acid),mPEG-PLGA]纳米粒处方,并进行体外释药评价。方法:乳化法制备穿心莲内酯mPEG-PLGA纳米粒,Box-Behnken设计-效应面法筛选穿心莲内酯mPEG-PLGA纳米粒最优处方,测定包封率、载药量、粒径及Zeta电位。采用质量分数为5%的甘露醇和乳糖等量混合物作为冻干保护剂,进一步制备成冻干粉,考察体外释药行为。结果:穿心莲内酯mPEG-PLGA纳米粒最佳处方为:mPEG-PLGA用量为589 mg、水相体积为70 mL、聚乙二醇硬脂酸酯15(Solutol HS 15)质量分数为1.2%,包封率为(82.07±1.62)%,载药量为(3.87±0.21)%,粒径为(179.56±9.19)nm,Zeta电位为(-10.91±1.84)mV。穿心莲内酯mPEG-PLGA纳米粒体外释药具有缓释特征,释药过程符合Weibull模型:lnln[1/(1-Mt/M∞)]=0.410 3lnt-1.434 1。结论:可用Box-Behnken设计-效应面法优化穿心莲内酯mPEG-PLGA纳米粒,为后续研究奠定基础。 相似文献
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目的 考察香菇多糖–番荔素纳米粒的性能,及其对小鼠黑色素瘤肺转移癌的体内外抑制效果。方法 采用反溶剂沉淀法制备香菇多糖–番荔素纳米粒,以动态光散射法测定粒径、分散系数(PDI)及Zeta电位,及其在不同生理介质(5%的葡萄糖、生理盐水、PBS的混悬液)中的稳定性;采用透射电子显微镜观察纳米粒的形态、大小;精确称量香菇多糖–番荔素纳米粒质量,并采用HPLC法测量番荔素中番荔辛,计算载药量;用酶标仪在540 nm处测量不同浓度(2、1.5、1、0.5、0.25、0.125 mg/mL)香菇多糖–番荔素纳米粒与5%葡萄糖溶液等渗液的吸光度,并计算溶血率;采用透析袋法考察香菇多糖–番荔素纳米粒的体外释放行为。用划痕实验与MTT实验对香菇多糖–番荔素纳米粒进行体外药效学考察。构建黑色素瘤肺转移癌小鼠模型,以紫杉醇注射液为阳性对照,对不同剂量香菇多糖–番荔素纳米粒进行体内药效学研究。结果 香菇多糖–番荔素纳米粒的粒径为(160.6±1.0)nm,PDI为0.082±0.023,Zeta电位为(-28.10±1.14)mV,透射电镜下呈球状。香菇多糖–番荔素纳米粒在5%的葡萄糖、血浆中稳定,无溶血现象;在体外可持续缓慢释放。体外研究结果显示,与番荔素原料药相比,香菇多糖–番荔素纳米粒对黑色素瘤B16F10细胞的迁移抑制作用及细胞毒性显著增加。体内药效学结果显示,香菇多糖–番荔素纳米粒iv给药14 d后,香菇多糖–番荔素纳米粒0.4 mg/mL组对黑色素瘤肺部转移抑制率可达到91.6%,S-100蛋白的表达也较模型组明显下调。结论 香菇多糖可作为稳定剂制备香菇多糖–番荔素纳米粒,香菇多糖–番荔素纳米粒对黑色素瘤肺转移癌初期具有显著的抑制作用。 相似文献
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《Saudi Pharmaceutical Journal》2022,30(9):1215-1242
The progress in the innovative nanocrystal synthesis process by using environmentally benign and low-priced nontoxic chemicals, solvents, and renewable sources remains a challenging task for researchers worldwide. The majority of the existing synthesis techniques engage in the potentially dangerous, for either human health or the environment. Current investigation has been centered on green synthesis processes to create novel nanomaterials, which are eco-friendly as well as safer for sustainable marketable feasibility. The current work provides the green synthesis method for gold nanoparticle (GNPs) synthesis using Commiphora myrrh (C.myrrh) extract. This simple method includes 6 ml of HAuCl4·3H2O treated with 4 ml C.myrrh extract having pH 4.5 after 80 min at 25 °C temperature. In this novel method, green synthesized GNPs characterized by UV–Vis, X_ray diffraction spectroscopy (XRD), zeta potential, fourier transform infrared (FT_IR), high_resolution transmission electron microscopy (HR_TEM), energy dispersive X_ray spectroscopy (EDXA), and dynamic light scattering (DLS). During the development successful antioxidant assay, the DPPH assay was applied. The cell toxicity of green synthesized GNPs was evaluated following an MTT assay against HCT-116 (colon cancer) and MCF-7 (breast cancer).Besides molecular docking in the δ-elemene for inhibitor to VEGFR‐2 domain revealed more negative docking score (?3.976) which is an excellent binding affinity to the C.myrrh@GNP. The synthesized GNPs showed antidiabetic, antibiotic, and antibacterial properties and anti_inflammatory inhibition against inhibiting COX-1, and COX-2 enzymes. In addition, molecular docking by Lindestrene (?3.806) and Furanoeudesma-1,3-dien (?3.912) against COX1 and COX2 respectively showed strong binding affinity. The molecular docking study evidenced the anti-inflammatory and cell toxicity study. 相似文献
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The discovery of effective drugs for the treatment of neurodegenerative disorders (NDs) is a deadlock. Due to their complex etiology and high heterogeneity, progresses in the development of novel NDs therapies have been slow, raising social/economic and medical concerns. Nanotechnology and nanomedicine evolved exponentially in recent years and presented a panoply of tools projected to improve diagnosis and treatment. Drug-loaded nanosystems, particularly nanoparticles (NPs), were successfully used to address numerous drug glitches, such as efficacy, bioavailability and safety. Polymeric nanoparticles (PNPs), mainly based on polylactic-co-glycolic acid (PLGA), have been already validated and approved for the treatment of cancer, neurologic dysfunctions and hormonal-related diseases. Despite promising no PNPs-based therapy for neurodegenerative disorders is available up to date. To stimulate the research in the area the studies performed so far with polylactic-co-glycolic acid (PLGA) nanoparticles as well as the techniques aimed to improve PNPs BBB permeability and drug targeting were revised. Bearing in mind NDs pharmacological therapy landscape huge efforts must be done in finding new therapeutic solutions along with the translation of the most promising results to the clinic, which hopefully will converge in the development of effective drugs in a foreseeable future. 相似文献
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目的:制备胡桃醌(juglone,Jug)聚乳酸-羟基乙酸(poly lactic-co-glycolic acid,PLGA)纳米粒(Jug-PLGA-NPs),并考察其理化性质、体外释放特征及对A375细胞的体外影响。方法:采用乳化挥发法制备Jug-PLGA-NPs,对其粒径、包封率、载药率以及体外释放特征进行考察;荧光显微镜观察PLGA-NPs在体外细胞的摄取情况,小动物活体成像仪观测PLGA-NPs在BALB/c荷瘤裸鼠尾静脉注射后体内的分布;用噻唑蓝(thiazolyl blue tetrazolium bromide,MTT)比色法检测其对A375细胞增殖抑制作用,流式细胞仪进行细胞凋亡率及细胞周期检测;蛋白免疫印迹法检测蛋白激酶B(protein kinase B,Akt),磷酸化-Akt(p-Akt),周期蛋白D1(cyclin D1)的表达情况。结果:制备的Jug-PLGA-NPs平均粒径为(149.6±21.5) nm,包封率为(68.39±2.51)%,载药率(5.07±0.98)%,具有良好的缓释特征。PLGA-NPs在体外细胞摄取和体内活体成像中具有良好的穿透和靶向性能。不同浓度Jug-PLGA-NPs均能明显抑制A375细胞增殖、促进细胞凋亡,呈明显时间浓度依赖性(P0.05),且48 h作用略优于等浓度Jug;其机制可能与调节Akt磷酸化水平,下调cyclin D1表达(P0.05),阻滞细胞于G0/G1期有关(P0.05)。结论:负载Jug的PLGA纳米微粒制备简便,具有良好的药物缓释、肿瘤靶向及抗肿瘤能力,为未来Jug的临床应用提供了一种新的药物剂型。 相似文献
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目的 制备环丙沙星固体脂质纳米粒并检测其抑菌效果。方法 以胆固醇为脂质,以吐温80为表面活性剂,采用乳化-低温固化法制备固体脂质纳米粒并对其进行表征,包括粒径、Zeta电位、载药量、包封率、分散性以及体外缓释。使用二倍稀释法测定药物对大肠杆菌的最低抑菌浓度。结果 透射电镜扫描可见环丙沙星-固体脂质纳米粒粒径呈球形,直径40~70nm;Zeta电位(-21.8±1.3) mV;包封率为77.54%;载药量31.10%;紫外-可见光谱见纳米粒中环丙沙星280nm处特征性吸收波峰;体外缓释72h的累计释放度为78.6%。环丙沙星固体脂质纳米粒的最低抑菌浓度为0.8μg/mL,环丙沙星最低抑菌浓度为1.6μg/mL。结论 采用乳化-低温固化法成功制备环丙沙星固体脂质纳米粒,方法简便。固体脂质纳米可提高环丙沙星抑菌效果。 相似文献