纳米磁性微球免疫伏安法测定乙肝表面抗原

采用化学键合法将乙肝抗体固化在自行制备的纳米磁性高分子功能微球表面 ,利用免疫夹心反应原理 ,捕获溶液中的乙肝表面抗原和标记有辣根过氧化物酶的乙肝第二抗体 .在外加磁场的作用下 ,抗体抗原结合物从样品溶液中分离 ,在含有邻氨基苯酚和过氧化氢的底液中 ,生成具有电活性的化合物 3 氨基吩呃嗪 ,用示差脉冲伏安法进行测定 .响应电流与乙肝表面抗原浓度分别在 0 2～ 1 0和 1 0～ 5 0 0ng·mL-1成线性关系 ,检出限达 0 0 60ng·mL-1.采用本方法检测血清中乙肝表面抗原 ,灵敏度大大高于目前临床采用的酶联免疫吸附法 .     

超支化聚合物作为放大信号的纳米磁性微球电化学免疫分析法

提出了一种基于超支化聚合物(HBP)固化酶标二抗作为放大信号和纳米磁球相结合的超灵敏的免疫分析新方法。首先羧基纳米磁性微球共价键合乙肝抗体(HBsAb)形成免疫磁性微球,然后与待测乙肝表面抗原(HBsAg)发生特异性结合,加入HBP标记的酶标二抗(HBPS)与结合的抗原结合发生夹心反应。在外加磁场的作用下,抗体抗原免疫复合物易从样品溶液中分离,在含有邻氨基苯酚和H2O2的底液中,快速生成具有电活性的化合物3-氨基吩呃嗪,用示差脉冲伏安法(DPV)测定响应电流,电流强度(I)与乙肝表面抗原浓度(c)在0.05～10.0μg/L范围内呈线性关系,线性回归方程为I(μA)=0.140+16.80 c(μg/L),相关系数r=0.9995,检出限达0.008μg/L,并用于实际样品的测定。     

应用纳米磁性球电化学检测特定序列DNA

采用分散聚合法制备纳米磁性羧基球,利用化学偶联法将末端修饰氨基的寡聚核苷酸固定在纳米磁性球表面,制成新型核酸探针,该探针可特异性结合目标单链寡聚核苷酸.在磁场作用下,将纳米磁珠与本体溶液分离并富集在电极表面,以中性红为嵌合指示剂,用示差脉冲伏安法测定杂交结果.经过条件优化,本法测定DNA的浓度线性范围为1.0×10^-6～5.0×10^-9mol/L,检出限为8.6×10^-10mol/L.     

氨基纳米磁球免疫电化学法检测甲胎蛋白的研究

提出了一种利用纳米磁球免疫分离,进行酶催化电化学检测甲胎蛋白的新方法。在自制含有活性氨基的纳米磁球表面,用戊二醛固化甲胎蛋白（AFP）抗体,利用免疫夹心反应原理,捕获溶液中的AFP抗原和标记有辣根过氧化物酶的AFP抗体。在外加磁场的作用下,抗体-抗原结合物从样品溶液中分离,在含有邻氨基苯酚和过氧化氢的底液中,生成具有电活性的化合物3-氨基吩呃嗪,用灵敏的示差脉冲伏安法测定。响应电流与AFP抗原浓度分别在1～5和5～400βg／L范围内呈线性关系,检出限达0．5βg／L。实验表明,该方法具有分离效率高、测定时间短、抗干扰性强等优点,尤其适用于分析复杂生物样品。应用此法于人血清样品中AFP的检测,灵敏度显著高于酶联免疫吸附法。     

孔雀石绿的磁性免疫层析快速检测方法研究

开发了一种适用于现场快速检测孔雀石绿(MG)的免疫层析试纸条,在超顺磁性纳米微球上偶联MG单克隆抗体作为检测探针,分别将孔雀石绿完全抗原(MG-B SA)和羊抗鼠IgG喷涂于NC膜的T线和C线.结果 发现,T线最佳喷涂量为0.25 mg/mL,抗体最佳偶联量为20 μg,构建的试纸条可在25 min内实现养殖用水及鱼肉...     

基于侧向磁泳的微流控芯片对两种磁性纳米球的同时分选

基于磁性纳米球在微流控芯片上的侧向磁泳,利用微流控芯片分选了不同磁响应性的磁球.提出了包含磁性纳米球聚集与偏移的理论模型,用于分析磁球在芯片上的侧向位移.在理论分析的基础上设计了芯片系统,使不同磁响应性的磁纳米球可以在芯片系统上依次被分选.实验结果表明,2种磁性纳米球的分选效率均可接受,且实验操作简单;磁响应性强的磁球可被完全分离,这对于珍贵分析样品的分选很有价值.该分选系统被成功用于同时分选样品中乙型肝炎病毒的DNA与丙型肝炎病毒的反转录DNA,在生化分析中具有广阔的应用前景.     

反相微乳液合成30～100nm磁性聚合物纳米微球

利用反相微乳液一步法成功地制备了磁性聚合物纳米微球,微球粒径在30～100nm左右,均一性较好,研究表明,Fe(Ⅱ)浓度对微乳液和微胶乳的稳定性有很大影响,碱的种类、AOT和单体的含量能控制微球粒径,用振动探针式磁强仪(VSM)测定了不同比例的[Fe(Ⅱ)]/[Fe(Ⅲ)]所合成的聚合物微球的磁性,发现温度对合成高磁饱和强度和超顺磁性起关键作用,合成的磁性聚合物微胶乳透明且稳定性较好.     

铜离子掺杂双金属纳米球免疫传感器检测前列腺特异性抗原

以比表面积大、结合位点多的金铂纳米球杂化二氧化锡石墨烯(GS-SnO2@Au-Pt)修饰玻碳电极,作为传感平台固定捕获抗体(Ab1),铜离子掺杂金银纳米球(Au-Ag@Cu²⁺)与检测抗体(Ab2)结合作为免疫探针,构建夹心型电化学免疫传感器,并用于检测前列腺特异性抗原(PSA)。基于Cu²⁺和Cu⁺之间的电子转移,以及金银双金属协同效应增强检测信号,通过方波伏安法(SWV)检测,在0.25 V处获得尖锐信号峰。结果表明,该免疫传感器具有较宽的线性范围(1 fg/mL~10 ng/mL)和较低的检出限(0.34 fg/mL),在PSA临床检测中有潜在应用前景。     

用于检测重金属离子的磁性荧光复合微球

采用静电逐层自组装的方法,首先将PSS和PAH聚电解质交替沉积在CaCO3中空微球表面,然后将Fe3O4磁性纳米粒子与CdSe量子点负载在中空微球表面不同的聚电解质层中,制备出具有磁性和荧光双重功能的复合微球,并将其作为荧光离子探针,研究了其对Cu2+和Pb2+离子检测的灵敏度、选择性及可行性。结果表明,复合微球显示出良好的磁性和荧光性能,对Cu2+和Pb2+离子的检测具有较高的灵敏度和选择性。尤为重要的是,可通过磁分离的方法将微球快速地从待测液中回收,从而能够避免量子点对环境造成的二次污染。     

用于检测重金属离子的磁性荧光复合微球

采用静电逐层自组装的方法,首先将PSS和PAH聚电解质交替沉积在CaCO₃中空微球表面,然后将Fe₃O₄磁性纳米粒子与CdSe量子点负载在中空微球表面不同的聚电解质层中,制备出具有磁性和荧光双重功能的复合微球,并将其作为荧光离子探针,研究了其对Cu²⁺和Pb²⁺离子检测的灵敏度、选择性及可行性。结果表明,复合微球显示出良好的磁性和荧光性能,对Cu²⁺和Pb²⁺离子的检测具有较高的灵敏度和选择性。尤为重要的是,可通过磁分离的方法将微球快速地从待测液中回收,从而能够避免量子点对环境造成的二次污染。     

基于免疫磁分离的荧光微球免疫层析法检测猪霍乱沙门氏菌

建立了基于免疫磁分离的荧光微球免疫层析法,检测猪霍乱沙门氏菌.待检样品经免疫磁分离富集和热洗脱处理后,用荧光微球免疫层析试纸条进行检测.每毫克纳米磁珠标记30μg抗体制备的免疫磁珠,对浓度为102 ～ 106 CFU/mL的猪霍乱沙门氏菌的捕获率均大于90％,特异性好;在pH=6时,以300μ,g/mg猪霍乱沙门氏菌单抗11D8-D4标记荧光微球,制备免疫荧光微球;以2.0 mg/mL猪霍乱沙门氏菌单抗5F11-B11喷涂检测线(T线),以1.0 mg/mL驴抗鼠IgG喷涂质控线(C线),制备免疫层析试纸条.采用建立的基于免疫磁分离的荧光微球免疫层析方法检测猪霍乱沙门氏菌,在PBS缓冲液中检出限为1.5×105 CFU/mL,牛奶中检出限为7.6×105 CFU/mL,与直接采用荧光微球免疫层析方法检测相比,检出限分别降低了10倍和200倍.本方法可有效富集牛奶中的沙门氏菌,避免了基质干扰,灵敏度大大提高,具有较好的应用前景.     

Rapid and specific detection of bacteria using bioluminescence

This paper describes rapid methods for the detection of very low numbers of bacteria. Specificity was obtained by the use of antibodies in immunomagnetic separation, a bacteriophage to allow targeted cell lysis, or a combination of both. The amplified endpoint assay used cell-derived adenylate kinase to convert added adenosine diphosphate (ADP) to adenosine triphosphate (ATP) which could then act as a substrate for the firefly bioluminescence reaction. Specific and non-specific assays were evaluated using Escherichia coli O157 as the test organism. Limits of detection of around 10² cells ml⁻¹ could be obtained with an upper end cut-off of around 10⁷ cells ml⁻¹. Depending on the level of specificity offered, the assays took from 5 min to just under 1 h.     

磁性纳米材料在循环肿瘤细胞检测中的研究进展

Recently, magnetic nanomaterials are widely applied in biomedical area owing to their unique physical and chemical properties.Herein, we introduce the progress of application of magnetic nanomaterials in cell separation, especially, in detection of circulating tumor cells from human whole blood.     

Probing the Adhesion of Hepatocellular Carcinoma HepG2 and SK‐Hep‐1 Cells

Carcinoma cell differentiation stage is an important indicator of cell behavior. For example, cell mobility is much higher for poorly‐differentiated hepatocellular carcinoma SK‐Hep‐1 cells than for well‐differentiated HepG2 cells. In this study, we have cultured HepG2 and SK‐Hep‐1 cells on chemically patterned polydimethylsiloxane (PDMS) substrates to observe differences in the adhesion properties and cell structure that occur due to the patterns. Both cell lines showed a preference for the hydrophobic regions on the patterned PDMS surface with SK‐Hep‐1 cells achieving a higher density than HepG2 for the same cell‐count solutions. Further, SK‐Hep‐1 cells adopted the square or hexagonal shape of the surface patterns while HepG2 cells maintained their more rounded shape. AFM force measurement arrays were also performed on the cell surfaces to measure and map adhesion values between the tip and cell surface membrane. These results demonstrate that, in addition to cell shape and size, adhesion expression in hepatocellular carcinoma cells is differentiation stage dependent. Further, the ability of the SK‐Hep‐1 cells to adopt the shape of the substrate pattern indicates they are more structurally labile, which may contribute to their higher mobility.     

Uptake of Well‐Defined,Highly Glycosylated,Pentafluorostyrene‐Based Polymers and Nanoparticles by Human Hepatocellular Carcinoma Cells

Chain length, size, composition, surface charge, and other properties of polymeric materials affect their recognition and uptake by cells and must be optimized to deliver polymers selectively to their target. However, it is often not possible to precisely modify selected properties without changing other parameters. To overcome these difficulties, well‐defined poly(pentafluorostyrene)‐based polymers are prepared that can be grafted via thiol/para‐fluorine “click” reaction with 1‐thio‐β‐D ‐glucose and 1‐thio‐β‐D ‐galactose. Fluorescence microscopy and flow cytometry show that nanoparticles are taken up by HepG2 cells to a higher degree than the respective water‐soluble polymers, and that internalization of both galactosylated homo‐ and nanoprecipitated block copolymers is enhanced.

     

聚乙烯吡咯烷酮保护荧光铜纳米团簇制备及其对乙醇的快速准确检测

乙醇含量的精确定量检测对于环境监测、临床诊断、食品检测以及饮用酒水都至关重要。以氯化铜（CuCl₂）为铜源、聚乙烯吡咯烷酮（PVP）为保护剂、2-巯基苯并噻唑（MBT）为稳定剂、抗坏血酸（AA）为还原剂,利用声化学还原法,以绿色简单、快速便捷的手段成功合成出具有橙色荧光的铜纳米团簇（PVP-Cu NCs）。利用紫外可见吸收光谱、荧光光谱、红外光谱、透射电镜和X射线光电子能谱技术研究其结构和性能,发现PVP-Cu NCs的最佳激发波长和发射波长分别为340和580 nm,其平均粒径为6.0 nm。PVP-Cu NCs可通过聚集诱导猝灭机制实现对乙醇的灵敏检测,其荧光强度与乙醇含量在体积分数5%~45%范围内呈现出良好的线性关系,且PVP-Cu NCs可制作成乙醇检测试纸,对乙醇进行可视化检测。     

Pyrrole-Based Fully Non-fused Acceptor for Efficient and Stable Organic Solar Cells

Organic solar cells (OSCs) are still suffering from the low light utilization and unstable under ultraviolet irradiation. To tackle these challenges, we design and synthesize a non-fused acceptor based on 1-(2-butyloctyl)-1H-pyrrole as π-bridge unit, denoted as GS70, which serves as active layer in the front-cell for constructing tandem OSCs with a parallel configuration. Benefiting from the well-complementary absorption spectra with the rear-cell, GS70-based parallel tandem OSCs exhibit an improved photoelectron response over the range between 600–700 nm, yielding a high short-circuit current density of 28.4 mA cm⁻². The improvement in light utilization translates to a power conversion efficiency of 19.4 %, the highest value among all parallel tandem OSCs. Notably, owing to the intrinsic stability of GS70, the manufactured parallel tandem OSCs retain 84.9 % of their initial PCE after continuous illumination for 1000 hours. Overall, this work offers novel insight into the molecular design of low-cost and stability non-fused acceptors, emphasizing the importance of adopting a parallel tandem configuration for achieving efficient light harvesting and improved photostability in OSCs.     

Biowaste-Derived,Highly Efficient,Reusable Carbon Nanospheres for Speedy Removal of Organic Dyes from Aqueous Solutions

The current work explores the adsorptive efficiency of carbon nanospheres (CNSs) derived from oil palm leaves (OPL) that are a source of biowaste. CNSs were synthesized at 400, 600, 800 and 1000 °C, and those obtained at 1000 °C demonstrated maximum removal efficiency of ~91% for malachite green (MG). Physicochemical and microscopic characteristics were analysed by FESEM, TEM, FTIR, Raman, TGA and XPS studies. The presence of surface oxygen sites and the porosity of CNSs synergistically influenced the speed of removal of MG, brilliant green (BG) and Congo red (CR) dyes. With a minimal adsorbent dosage (1 mg) and minimum contact time (10 min), and under different pH conditions, adsorption was efficient and cost-effective (nearly 99, 91 and 88% for BG, MG and CR, respectively). The maximum adsorption capacities of OPL-based CNSs for BG were 500 and 104.16 mg/g for MG and 25.77 mg/g for CR. Adsorption isotherms (Freundlich, Langmuir and Temkin) and kinetics models (pseudo-first-order, pseudo-second-order and Elovich) for the adsorption processes of all three dyes on the CNSs were explored in detail. BG and CR adsorption the Freundlich isotherm best, while MG showed a best fit to the Temkin model. Adsorption kinetics of all three dyes followed a pseudo-second-order model. A reusability study was conducted to evaluate the effectiveness of CNSs in removing the MG dye and showed ~92% efficiency even after several cycles. Highly efficient CNSs with surface oxygen groups and speedy removal of organic dyes within 10 min by CNSs are highlighted in this paper.     

A Rapid and Efficient Strategy for Quality Control of Clinopodii herba Encompassing Optimized Ultrasound-Assisted Extraction Coupled with Sensitive Variable Wavelength Detection

Clinopodii herba is a folk herbal medicine for treatments of hemorrhagic disorders. However, there is not even a quantitative standard for clinopodii herba deposited in the Chinese Pharmacopoeia. The development of a strategy for rapid and efficient extraction and simultaneous detection of multiple components in clinopodii herba is therefore of great value for its quality evaluation. Here, a variable wavelength strategy was firstly applied to quantity multiple components by segmental monitoring by UHPLC with diode array detector following ultrasound-assisted extraction. The parameters of ultrasound-assisted extraction were optimized using single factor optimization experiments and response surface methodology by a Box–Behnken design combined with overall desirability. Subsequently, a rapid, efficient, and sensitive method was applied for simultaneous determination of eleven compounds, which represented the major and main types of components in clinopodii herba. Moreover, the performance of the validated method was successfully applied for the quality control of various batches of clinopodii herba and provided sufficient supporting data for the optimum harvest time. The Box-Behnken-optimized ultrasound-assisted extraction coupled with variable wavelength detection strategy established in this work not only improves the quality control of clinopodii herba, but also serves as a powerful approach that can be extended to quality evaluation of other traditional Chinese medicines.