中文摘要：

基于微悬臂梁技术的DNA生物传感器的纳米挠度与核苷长度、嫁接密度、杂交率、重力、盐溶液浓度、时间、温度变化、缓冲液流场特性等诸多因素有关。利用Zhang两变量方法,建立了静态模式中自重作用下微梁正应力、切应力、层间挤压应力及其挠度预测的解析模型。作为应用,采用McKendry实验参数,研究了重力因素对静态纳米挠度的影响,发现参考梁技术中生物层自重对纳米挠度的影响可以忽略,但单梁技术中非生物层自重对纳米挠度的影响不可以忽略;同时,利用DNA生物传感器表面应力的Zhang解析模型,考虑自重和表面应力因素,给出了微梁的最优尺寸,从而可使单梁技术中自重因素对静态挠度的影响降到最低。

英文摘要：

The nanomechanical deflection of microcantilever-based DNA biosensor is related to many factors such as nucleotide length,grafting density,hybridization ratio,gravity,salt solution concentration,time,temperature fluctuation,the characteristic of buffer flow field,etc.By Zhang＇s two-variable method,an analytical model to predict normal stress,shear stress,extrusion stress between adjacent layers and the deflection of a microcantilever beam induced by gravity in static mode was provided.As its applications,the parameters in McKendry＇s experiment were adopted to study the influence of gravitational factors on static nanomechanical deflections,and the results showed that the influence of gravitational factor of the biolayer on nanomechanical deflection can be neglected in reference beam technology,while that of non-biolayers can not be neglected in single beam technology;at the same time,the Zhang＇s analytical model for surface stress change of a DNA biosensor is used to provide the optimal geometry of the beam,considering factors of surface stress and gravity in order to make the lowest influence of gravitational factor on nanomechanical deflection in single beam technology.