应用生物素—亲和素间接免疫荧光法检测支原体

应用生物素-亲和素系统导入间接免疫荧光法,对不同株的支原体进行了初步检测。结果生物素-亲和素间接免疫荧光法(ABS—IFA)比普通间接免疫荧光法敏感度高百倍以上。在ABS—IFA方法中,阳性支原体部位苹果绿染色明亮、清晰,而背景浅且较干净。     

生物素—链霉亲和素免疫组化法检测脊髓灰质炎病毒抗体

应用生物素—键霉亲和素免疫组化法检测自然人群和服苗儿童63份血清中三型脊灰抗体IgG，同时与中和试验对比，阴阳性总符合率均在92％以上，抗体液度呈正相关。组化法不仅敏感性高于中和法，而且较中和法简便、快速。故适用于脊灰抗体检测。     

人巨细胞病毒IgM抗体生物素-亲和素单克隆抗体捕获时间分辨荧光免疫法检测试剂盒的研制与评价

目的建立人巨细胞病毒IgM(human cytomegalovirus IgM,HCMV IgM)抗体生物素-亲和素单克隆抗体捕获时间分辨荧光免疫法(biotin-avidin monoclonal antibody capture time-resolved fluoroimmunoassay,BA Mac TrFIA)检测试剂盒,并对其性能进行评价。方法采用鼠抗IgMμ链单克隆抗体(monoclonal antibody,McAb)作为固相反应板的包被抗体,生物素(biotin)标记的HCMV基因重组抗原作为桥接抗原,链酶亲和素(SA)标记铕(Eu3+)作为示踪物,配制以β-萘甲酰三氟丙酮为主要成分的增强液,应用BA Mac TrFIA法进行HCMV IgM抗体的检测,对连续制备的3批试剂盒的最低检测限、重复性、阴性参考品符合率、阳性参考品符合率、热稳定性进行评价,并与巨细胞病毒IgM抗体诊断试剂盒同时对1 020份血清或血浆样本进行临床研究比对试验,采用Kappa检验进行一致性分析。结果选择4μg/ml作为鼠抗IgMμ链McAb最佳包被浓度,1∶10 000稀释作为HCMV-Bio最佳工作浓度,1∶1 500稀释作为SA-Eu3+最佳工作浓度,试剂盒参考值建议为阴性对照品检测荧光值(negative control counter,NCx)×2.1;连续制备的3批试剂盒最低检测限、重复性、阴性参考品符合率、阳性参考品符合率均达到国家检定标准;于37℃恒温箱放置6 d后,检测性能无明显改变;临床研究比对试验Kappa指数为1,一致程度达100%。结论成功制备了HCMV IgM BA Mac TrFIA法检测试剂盒,该试剂盒灵敏度高,精密性较好,与同类产品检测结果相关性好,为临床HCMV lgM抗体的检测提供科学、可靠的诊断依据。     

SEDS技术制备水飞蓟素纳米颗粒

采用超临界流体增强溶液分散技术(SEDS)从丙酮溶液中沉淀制备水飞蓟素纳米颗粒,用扫描电镜考察了工艺参数温度(25℃,32℃,40℃,50℃)、压力(9.5MPa,12MPa,15MPa,20MPa)、溶液浓度(40mg.mL-1,60mg.mL-1,80mg.mL-1,100mg.mL-1,120mg.mL-1)对颗粒形貌、粒径尺寸及粒径尺寸分布的影响。结果表明,所得颗粒均为实心微球;温度和溶液浓度是影响粒径尺寸的主要因素,降低温度和浓度能够显著减小粒径尺寸;温度也对粒径尺寸分布影响显著,在40℃时,粒径尺寸分布较窄,当温度高于或低于40℃时,粒径尺寸分布明显变宽。通过优化工艺参数,在9.5MPa,40℃,60mg.mL-1的条件下,制备出粒径尺寸介于100~300nm的水飞蓟素纳米颗粒。     

结核分枝杆菌杂交信号放大检测方法的建立

目的建立结核分枝杆菌杂交信号放大检测方法。方法构建纳米颗粒信号放大载体,建立杂交信号放大方法,检测标本中结核分枝杆菌特异性的插入序列IS6110。应用该方法检测124份临床结核患者标本,并与细菌培养和生化鉴定法的检测结果进行比较,确定该方法的灵敏度和特异性。结果杂交信号放大方法检测临床标本的灵敏度为87.7%,特异性为92.2%,假阳性率为7.8%,假阴性率为12.3%。结论已建立具有较高灵敏度和特异性的杂交信号放大检测方法,该方法操作简便、快速,可作为结核分枝杆菌临床标本的检测方法。     

德国利用纳米颗粒作为药物载体治疗肺癌

德国科学家最近开发出了一种治疗肺癌的全新方法，利用微小的纳米颗粒作为药物载体，将药物定向送到肺部癌细胞处，阻断癌细胞的生长。肺癌目前属于还比较难治愈和死亡率较高的癌症，德国每年平均约4.6万人死于肺癌。德国萨尔布吕肯大学生物医药和制药技术研究所的克劳斯·雷哈教授致力于研究纳米颗粒来治疗癌症，他介绍说，     

链霉亲和素-蛋白A融合蛋白基因在大肠杆菌中的表达

将合链霉亲和亲-蛋白A（Streptavidin－proteinA）融合蛋白基因的表达质粒pTSAPA导入大肠杆菌BL21（DE3），成功地表达了该融合蛋白，经SIJS－PAGE及免疫印迹等方法证实该蛋白既具有IgG的结合活性，又具生物素结合活性。     

纳米颗粒在分析检测领域的应用

纳米生物技术是国际生物技术领域的前沿与热点,功能性纳米颗粒由于独特的光学性能、高的表面积及尺寸依赖性等性能,被应用在分析检测领域,具有很好的发展前景.概述了几种常见功能性纳米颗粒的特性、标记及其在分析检测领域的应用.     

纳米Fe3O4颗粒的表面包覆及其在磁性氧化铝载体制备中的应用

通过对共沉淀得到的Fe3O4磁性纳米颗粒在硅酸钠溶液中进行酸化处理，获得了表面包覆SiO2层的Fe3O4磁性组份. 由于SiO2的位阻作用，限制了Fe3O4微晶的团聚与继续生长，使Fe3O4核心分散在产物中保持较小的晶粒尺寸，包覆产物表现出超顺磁性，同时提高了磁性组份的耐候性. 将上述磁性组份加入到氢氧化铝溶胶中，采用内凝胶法(油中成型法)制备出磁性球形氧化铝载体，磁性组份外表的SiO2包覆层的隔离作用防止了磁性核心与载体组份之间发生的反应，也避免了铁组份可能对后续负载的催化剂活性组份造成的不良影响. 制备的磁性氧化铝载体具备超顺磁性，磁性氧化铝载体的磁性能因内部磁性核心组份的改变而发生一定变化.     

载体和稳定剂调变纳米颗粒气相催化性能研究进展

金属纳米颗粒极不稳定,易于聚集,导致其尺寸变大和形貌改变,影响催化性能,纳米颗粒需要负载在高比表面积的载体上或在稳定剂保护条件下进行反应。纳米颗粒所处环境,如载体的性质以及稳定剂的类型对纳米催化剂的表面电子结构具有重要影响,因而对其催化性能有重要的影响。     

新型红细胞-纳米粒子载体系统的研究进展

介绍了红细胞-纳米粒子这种新型载体系统在药物运输、核磁共振成像等方面的研究进展,为扩展红细胞-纳米粒子载体系统的研究及应用提供了参考.     

The Future of Point-of-Care Nucleic Acid Amplification Diagnostics after COVID-19: Time to Walk the Walk

Since the onset of the COVID-19 pandemic, over 610 million cases have been diagnosed and it has caused over 6.5 million deaths worldwide. The crisis has forced the scientific community to develop tools for disease control and management at a pace never seen before. The control of the pandemic heavily relies in the use of fast and accurate diagnostics, that allow testing at a large scale. The gold standard diagnosis of viral infections is the RT-qPCR. Although it provides consistent and reliable results, it is hampered by its limited throughput and technical requirements. Here, we discuss the main approaches to rapid and point-of-care diagnostics based on RT-qPCR and isothermal amplification diagnostics. We describe the main COVID-19 molecular diagnostic tests approved for self-testing at home or for point-of-care testing and compare the available options. We define the influence of specimen selection and processing, the clinical validation, result readout improvement strategies, the combination with CRISPR-based detection and the diagnostic challenge posed by SARS-CoV-2 variants for different isothermal amplification techniques, with a particular focus on LAMP and recombinase polymerase amplification (RPA). Finally, we try to shed light on the effect the improvement in molecular diagnostics during the COVID-19 pandemic could have in the future of other infectious diseases.     

Amplicon Competition Enables End‐Point Quantitation of Nucleic Acids Following Isothermal Amplification

It is inherently difficult to quantitate nucleic acid analytes with most isothermal amplification assays. We developed loop‐mediated isothermal amplification (LAMP) reactions in which competition between defined numbers of “false” and “true” amplicons leads to order of magnitude quantitation by a single endpoint determination. These thresholded LAMP reactions were successfully used to directly and quantitatively estimate the numbers of nucleic acids in complex biospecimens, including directly from cells and in sewage, with the values obtained closely correlating with qPCR quantitations. Thresholded LAMP reactions are amenable to endpoint readout by cell phone, unlike other methods that require continuous monitoring, and should therefore prove extremely useful in developing one‐pot reactions for point‐of‐care diagnostics without needing sophisticated material or informatics infrastructure.     

Isothermal Nucleic Acid Amplification to Detect Infection Caused by Parasites of the Trypanosomatidae Family: A Literature Review and Opinion on the Laboratory to Field Applicability

Isothermal amplification of nucleic acids has the potential to be applied in resource-limited areas for the detection of infectious agents, as it does not require complex nucleic purification steps or specific and expensive equipment and reagents to perform the reaction and read the result. Since human and animal infections by pathogens of the Tryponasomatidae family occur mainly in resource-limited areas with scant health infrastructures and personnel, detecting infections by these methodologies would hold great promise. Here, we conduct a narrative review of the literature on the application of isothermal nucleic acid amplification for Trypanosoma and Leishmania infections, which are a scourge for human health and food security. We highlight gaps and propose ways to improve them to translate these powerful technologies into real-world field applications for neglected human and animal diseases caused by Trypanosomatidae.     

氧化铝载体的回收

以废氧化铝载体为原料，在一定温度下与盐酸反应生成了三氯化铝，再经酸化、中和、干燥等处理，最后得到可以利用的氧化铝载体。盐酸的最适宜浓度是７ｍｏｌ／Ｌ，氧化铝载体的回收获得了较好的经济效益。     

酶固定化无机载体材料的研究进展

近年来,酶固定化技术已在食品工业、医药、精细化学品工业,尤其是手性化合物等行业得到广泛应用,在废水处理方面也取得了一定进展。然而,载体材料的物理和化学性能直接影响固定化酶的催化活性。本文介绍了酶固定化常用无机载体材料一传统的无机载体材料、改性无机载体材料以及复合载体材料,并对酶固定化用无机载体材料的发展进行了展望。     

A Novel Isothermal Assay of Borrelia burgdorferi by Recombinase Polymerase Amplification with Lateral Flow Detection

A novel isothermal detection for recombinase polymerase amplification with lateral flow (LF-RPA) was established for Borrelia burgdorferi (B. burgdorferi) detection in this study. This assay with high sensitivity and specificity can get a visible result without any additional equipment in 30 min. We designed a pair of primers according to recA gene of B. burgdorferi strains and a methodology evaluation was performed. The results showed that the RPA assay based on the recA gene was successfully applied in B. burgdorferi detection, and its specific amplification was only achieved from the genomic DNA of B. burgdorferi. The detection limit of the new assay was about 25 copies of the B. burgdorferi genomic DNA. Twenty Lyme borreliosis patients’ serum samples were detected by LF-RPA assay, real-time qPCR and nested-PCR. Results showed the LF-RPA assay is more effective than nested-PCR for its shorter reaction time and considerably higher detection rate. This method is of great value in clinical rapid detection for Lyme borreliosis. Using the RPA assay might be a megatrend for DNA detection in clinics and endemic regions.