A novel gold-label silver-stain electrochemical immunosensor was developed based on polythioninegold nanoparticles（PTh-Au） modified glassy carbon electrode（GCE） as a platform and secondary antibody labeled Au NPs...A novel gold-label silver-stain electrochemical immunosensor was developed based on polythioninegold nanoparticles（PTh-Au） modified glassy carbon electrode（GCE） as a platform and secondary antibody labeled Au NPs（Ab;-Au） as immumoprobe for carcinoembryonic antigen（CEA） detection. The sandwich-type biosensor adopted anodic stripping voltammetry to detect silver stripping signal when the Ab;-Au of the formed immunocomplexes were stained with silver. The optimized detection conditions were investigated. The effect of different electrochemical responses at various concentrations of CEA was checked by anodic stripping voltammetry. This immunosensor showed a low detection limit of 0.055 ng/mL and a wide linear calibration of 0.1-120 ng/mL（R;=0.99856）. Moreover, this immunoassay also existed the advantages of good reproducibility, stability and selectivity. Thus, this immunosensing protocol may provide a potential application for effective clinical detection of CEA.展开更多
Poly（tetrafluoroethylene） （PTFE） was treated with plasma in a mixture of nitrogen and hydrogen （1 ： 2 in volume）. X-ray photoelectron spectroscopy （XPS） demonstrated the success of amino group grafting. The a...Poly（tetrafluoroethylene） （PTFE） was treated with plasma in a mixture of nitrogen and hydrogen （1 ： 2 in volume）. X-ray photoelectron spectroscopy （XPS） demonstrated the success of amino group grafting. The as-treated PTFE slices were successively applied to the in situ synthesis of oligonucleotides. With the detection of gold-label-silver-stain, the hybridization signals were recorded with a gel document and analysis system. A target DNA concentration as low as 10 pmol/L could be detected. The complementary and mismatched sequences were distinguished clearly, and the ratio of background-subtracted gray scale values for perfect match ： 1 base mismatch ： 2 base mismatch ： 3 base mismatch was 72 ： 44.4 ： 22.5 ： 11.4. The sensitivity of in situ synthesis system was 1 order of magnitude higher than that of spotting system, and the signal of the former was about 1.5 times stronger than that of the latter under the same target DNA concentration. These plasma modified PTFE slices might open novel prospects for the in situ synthesis of DNA micro-arrays.展开更多
稻曲病菌在PD 液体培养基中生长良好,并能产生对植物细胞具有高度生物抑制活性的毒素。生物学活性测定袁明,用100%的甲醇能提取稻曲病菌液体培养物中的粗毒素。粗毒素对小麦胚根胚芽的生长有强烈的抑制作用。把毒素主要成分Ustiloxin A ...稻曲病菌在PD 液体培养基中生长良好,并能产生对植物细胞具有高度生物抑制活性的毒素。生物学活性测定袁明,用100%的甲醇能提取稻曲病菌液体培养物中的粗毒素。粗毒素对小麦胚根胚芽的生长有强烈的抑制作用。把毒素主要成分Ustiloxin A 和BSA 偶联后,制备了抗血清,ELISA 检测表明用两种偶联剂偶联所制备的抗体效价分别为1∶20000和1∶6000。进一步的免疫胶体金标记分析表明,所制备的抗体能与茼丝中分泌的毒素特异性结合,说明所获得的抗体是特异性的。展开更多
A novel, sensitive anodic stripping volammetric immunoassay was developed based on silver-enhanced immuno-gold label. The immunoreaction was performed in a polystyrene microwell by using the sandwich format. Primary a...A novel, sensitive anodic stripping volammetric immunoassay was developed based on silver-enhanced immuno-gold label. The immunoreaction was performed in a polystyrene microwell by using the sandwich format. Primary antibodies specific for C-3(complement Ⅲ) were adsorbed passively on the walls of a polystyrene microwell. The C-3 analyte was first captured by the primary antibody and then sandwiched by a secondary colloidal gold-labeled antibody. The addition of the silver enhancement solution results in the precipitation of a large amount of silver on colloidal gold labels due to the catalytic reduction which, after silver metal dissolution in an acidic solution, was determined by anodic stripping voltammetry(ASV) at a glassy-carbon electrode. The influence of some immunoassay conditions upon the anodic stripping peak current was examined and optimized. The anodic stripping peak current depended linearly on the logarithm of C-3 mass concentration over the range of 7.2 ng/mL to 7.33 μg/mL and a detection limit as low as 7ng/mL is achieved. The anodic stripping volammetric immunoassay was applied to the determination of C-3 concentration in human serum with satisfactory results.展开更多
对广州一例未知病原体感染引起的皮肤病患者血样进行免疫学和分子生物学鉴定,以确定其病原体。取静脉血,用Leish r K39 dipstick金标试纸检测利什曼原虫抗体情况。取皮损处组织,75%乙醇固定后,提取基因组DNA。用两对利什曼原虫种特异性...对广州一例未知病原体感染引起的皮肤病患者血样进行免疫学和分子生物学鉴定,以确定其病原体。取静脉血,用Leish r K39 dipstick金标试纸检测利什曼原虫抗体情况。取皮损处组织,75%乙醇固定后,提取基因组DNA。用两对利什曼原虫种特异性引物LITSR-L5.8S和NAGTL1-NAGTL4分别PCR扩增利什曼原虫核糖体DNA内转录间隔区1和N-乙酰氨基葡萄糖苷转移酶的基因片段,扩增产物进行测序和BLAST序列分析。Leish r K39 dipstick金标试纸检测结果呈弱阳性。PCR结果显示,引物LITSR-L5.8S和NAGTL1-NAGTL4分别扩增出约404 bp和1 405 bp的片段,两片段序列与硕大利什曼原虫(Leishmania major)相应序列的相似性均为99.7%。其序列Gen Bank登录号分别为KU975160和KX150476。确诊该皮肤病患者为输入性皮肤利什曼病病例,病原体为硕大利什曼原虫。展开更多
基金financial supports of the National Natural Science Foundation of China(Nos.61471168,61571187)China Postdoctoral Science Foundation(No.2016T90403)+2 种基金Postdoctoral Science Foundation of Jiangsu Province(No.1601021A)the Natural Science Foundation of Hunan Province(No.2017JJ209)Hunan Key Research Project(No.2017SK2174)
文摘A novel gold-label silver-stain electrochemical immunosensor was developed based on polythioninegold nanoparticles（PTh-Au） modified glassy carbon electrode（GCE） as a platform and secondary antibody labeled Au NPs（Ab;-Au） as immumoprobe for carcinoembryonic antigen（CEA） detection. The sandwich-type biosensor adopted anodic stripping voltammetry to detect silver stripping signal when the Ab;-Au of the formed immunocomplexes were stained with silver. The optimized detection conditions were investigated. The effect of different electrochemical responses at various concentrations of CEA was checked by anodic stripping voltammetry. This immunosensor showed a low detection limit of 0.055 ng/mL and a wide linear calibration of 0.1-120 ng/mL（R;=0.99856）. Moreover, this immunoassay also existed the advantages of good reproducibility, stability and selectivity. Thus, this immunosensing protocol may provide a potential application for effective clinical detection of CEA.
基金Project supported by Hunan Province Natural Science Foundation （No. 04jj40023）, the Trans-century Training Program Foundation for the Talents by the Ministry of Education of China, and the Post-doctoral Science Foundation of China.
文摘Poly（tetrafluoroethylene） （PTFE） was treated with plasma in a mixture of nitrogen and hydrogen （1 ： 2 in volume）. X-ray photoelectron spectroscopy （XPS） demonstrated the success of amino group grafting. The as-treated PTFE slices were successively applied to the in situ synthesis of oligonucleotides. With the detection of gold-label-silver-stain, the hybridization signals were recorded with a gel document and analysis system. A target DNA concentration as low as 10 pmol/L could be detected. The complementary and mismatched sequences were distinguished clearly, and the ratio of background-subtracted gray scale values for perfect match ： 1 base mismatch ： 2 base mismatch ： 3 base mismatch was 72 ： 44.4 ： 22.5 ： 11.4. The sensitivity of in situ synthesis system was 1 order of magnitude higher than that of spotting system, and the signal of the former was about 1.5 times stronger than that of the latter under the same target DNA concentration. These plasma modified PTFE slices might open novel prospects for the in situ synthesis of DNA micro-arrays.
文摘A novel, sensitive anodic stripping volammetric immunoassay was developed based on silver-enhanced immuno-gold label. The immunoreaction was performed in a polystyrene microwell by using the sandwich format. Primary antibodies specific for C-3(complement Ⅲ) were adsorbed passively on the walls of a polystyrene microwell. The C-3 analyte was first captured by the primary antibody and then sandwiched by a secondary colloidal gold-labeled antibody. The addition of the silver enhancement solution results in the precipitation of a large amount of silver on colloidal gold labels due to the catalytic reduction which, after silver metal dissolution in an acidic solution, was determined by anodic stripping voltammetry(ASV) at a glassy-carbon electrode. The influence of some immunoassay conditions upon the anodic stripping peak current was examined and optimized. The anodic stripping peak current depended linearly on the logarithm of C-3 mass concentration over the range of 7.2 ng/mL to 7.33 μg/mL and a detection limit as low as 7ng/mL is achieved. The anodic stripping volammetric immunoassay was applied to the determination of C-3 concentration in human serum with satisfactory results.
