School of Engineering, University of British Columbia, 333 University Way, Kelowna, BC V1V1V7, Canada.
Department of Mechanical & Industrial Engineering, University of Toronto, Toronto, ON M5S 3G8, Canada.
Sensors (Basel). 2019 Jan 10;19(2):258. doi: 10.3390/s19020258.
, an intestinal protozoan pathogen, is one of the leading causes of diarrhea in healthy adults and death in children. Detection of oocysts has become a high priority to prevent potential outbreaks. In this paper, a label-free interdigitated-based capacitive biosensor has been introduced for the detection of oocysts in water samples. Specific anti- monoclonal antibodies (IgG3) were covalently immobilized onto interdigitated gold electrodes as the capture probes, and bovine serum albumin was used to avoid non-specific adsorption. The immobilization of the antibodies was confirmed by measuring the change in the contact angle. The detection was achieved by measuring the relative change in the capacitive/dielectric properties due to the formation of -antibody complex. The biosensor has been tested for different concentrations of . The results show that the biosensor developed can accurately distinguish different numbers of captured cells and densities on the surface of the biosensor. The number of oocysts captured on the electrode surface was confirmed using a fluorescein isothiocyanate (FITC) immunofluorescence assay. The response from the developed biosensor has been mainly dependent on the concentration of under optimized conditions. The biosensor showed a linear detection range between 15 and 153 cells/mm² and a detection limit of 40 cells/mm². The label-free capacitive biosensor developed has a great potential for detecting in environmental water samples. Furthermore, under optimized conditions, this label-free biosensor can be extended for detection of other biomarkers for biomedical and environmental analyses.
贾第鞭毛虫是一种肠道原生动物病原体，是导致健康成年人腹泻和儿童死亡的主要原因之一。检测 包囊已成为预防潜在爆发的首要任务。在本文中，介绍了一种无标记的叉指式基于电容的生物传感器，用于检测水样中的 包囊。特异性抗-单克隆抗体（IgG3）被共价固定在叉指金电极上作为捕获探针，牛血清白蛋白被用来避免非特异性吸附。通过测量接触角的变化来确认抗体的固定。通过测量由于 -抗体复合物的形成而导致的电容/介电性质的相对变化来进行检测。该生物传感器已针对不同浓度的 进行了测试。结果表明，所开发的生物传感器可以准确地区分表面上不同数量的捕获细胞和密度。使用异硫氰酸荧光素（FITC）免疫荧光测定法来确认电极表面上捕获的 包囊数量。在优化条件下，开发的生物传感器的响应主要取决于 的浓度。该生物传感器在 15 到 153 个细胞/mm²之间表现出线性检测范围，检测限为 40 个细胞/mm²。所开发的无标记电容生物传感器在检测环境水样中的 方面具有很大的潜力。此外，在优化条件下，这种无标记的生物传感器可以扩展到用于检测生物医学和环境分析中的其他生物标志物。
