A HIGHLY SENSITIVE MICROCANTILEVER-BASED IMMUNOSENSOR ARRAY

0617240Mulchandani总体目标是开发一种新型的基于微悬臂梁的阵列免疫传感器，该传感器具有高灵敏度、高选择性、精确、准确、快速、可现场部署、稳健、低成本，并允许同时检测和定量小分析物。该传感器将基于力测量传导机制和受体-配体生物相互作用识别原理的结合，实现高灵敏度和选择性。三硝基甲苯 (TNT)、莠去津 (ATZ) 和生物素将作为模型分析物进行研究。将使用定向进化产生针对 TNT 和 ATZ 的单链抗体片段 (scFv)，其对各自类似物具有低亲和力和高解离率。选定的 scFv 将固定在微悬臂梁尖端上，用类似物功能化的琼脂糖珠将悬浮在微悬臂梁尖端上，并测量粘附力。向该系统引入具有较高亲和力和高结合率的目标分析物将导致附着的珠子移位，从而导致粘合力破裂。断开连接所需的时间与分析物的浓度相关。通过这项研究获得的知识和开发的传感器将为医疗保健、国土安全、食品监测和质量控制等领域的应用引入新颖的生物传感器设计概念。拟议的工作将对分子生物学和物理学传统领域以及传感器/生物传感器、纳米生物技术和微加工等新兴多学科领域的下一代劳动力的教学和培训产生影响。

0617240MulchandaniThe overall objective is to develop a novel microcantilever-based array immunosensor which is highly-sensitive, highly selective, precise, accurate, rapid, field-deployable, robust, low-cost and allows the simultaneous detection and quantification of small analytes. The proposed sensor will be based on the combination of the force measurement transduction mechanism and the receptor-ligand biological interaction recognition principle to realize the high sensitivity and selectivity. Trinitrotoluene (TNT), atrazine (ATZ), and biotin will be studied as model analytes. Single chain antibody fragment (scFv) against TNT and ATZ with low affinity and high off-rate for the respective analogs will be generated using directed evolution. The selected scFv will be immobilized on the microcantilever tip to which agarose beads functionalized with the analog will be suspended and the adhesive force measured. The introduction of the target analyte that has higher affinity and high on-rate to this system will result in the displacement of the attached bead and hence rupture of the adhesive force. The time required to rupture the linkage will be correlated to the concentration of the analyte. The knowledge gained and the sensors developed through this research will introduce novel biosensor design concepts for the applications in health care, homeland security, food monitoring and quality control, etc. The proposed effort will have impact on teaching and training of the next generation work force in the traditional areas of molecular biology and physics and the emerging multidisciplinary subject of sensors/biosensors, nanobiotechnology and microfabrication.