PEMC sensor's mass change sensitivity is 20 pg/Hz under liquid immersion.
PEMC sensor's mass change sensitivity is 20 pg/Hz under liquid immersion.
复制标题
PEMC传感器在液浸状态下的质量变化灵敏度为20 pg/Hz。
DOI：
10.1016/j.bios.2005.11.020
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发表时间：
2006
影响因子：
12.6
通讯作者：
Mutharasan,Raj
中科院分区：
文献类型：
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作者：
Campbell,GossettA;Mutharasan,Raj
为了提高谐振压电激励毫米级悬臂梁 (PEMC) 传感器的质量变化灵敏度，我们缩短了其长度并消除了一层复合结构。结果，第二弯曲模式的质量灵敏度增加了两个数量级（从 10−9 到 10−11g/Hz），并且谐振频率增加了 5kHz 以上。我们通过检测 700 个细胞/mL 的模型病原体 A 组链球菌 (GAS) 来证明修饰的效果。第二模式在浓度为700、7×103、7×105、7×106、7×107和7×109细胞/mL时的共振频率变化分别导致3.1±0.5、11.6±1、15.7±1、25.7±0.15、28.5±2和40.5±3ng (n=3) 病原体附着。提出并验证了结合的动力学模型。发现观察到的结合速率常数在 0.051–0.166min−1 范围内。我们报告的结果的意义在于，改进的PEMC传感器具有高质量灵敏度，可以在液体浸没条件下检测到非常低浓度的病原体。
To enhance the mass change sensitivity of the resonating piezoelectric-excited millimeter-sized cantilever (PEMC) sensors, we reduced its length and eliminated one layer of its composite structure. As a result the mass sensitivity of the second flexural mode increased by two orders of magnitude (from 10−9to 10−11g/Hz) and the resonant frequency increased by more than 5kHz. We demonstrate the effects of modification by detecting a model pathogen Group A Streptococcus (GAS) at 700cells/mL. The resonant frequency change of the second mode at concentrations of 700, 7×103, 7×105, 7×106, 7×107, and 7×109cells/mL resulted in, respectively, 3.1±0.5, 11.6±1, 15.7±1, 25.7±0.15, 28.5±2, and 40.5±3ng (n=3 for all) of pathogen attachment. A kinetic model for the binding is proposed and verified. The observed binding rate constant was found to be in the range of 0.051–0.166min−1. The significance of the results we report is that the modified PEMC sensors have high mass sensitivity that pathogens can be detected at very low concentration under liquid immersion conditions.