Validation of antibody-based recognition by piezoelectric transducers through electroacoustic admittance analysis
Validation of antibody-based recognition by piezoelectric transducers through electroacoustic admittance analysis
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DOI：
10.1016/s0956-5663(97)00139-5
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发表时间：
1998-03-01
影响因子：
12.6
通讯作者：
Therasse, J
中科院分区：
文献类型：
--
作者：
Bizet, K;Gabrielli, C;Therasse, J
基于压电换能器的免疫传感器的开发因其具有吸引力的潜力而受到广泛研究。石英晶体微天平（QCM）可以给出直接响应信号，该信号表征固定在表面换能器上的敏感层与待检测的分析物之间的结合事件。然而，对于小生物分子，例如一些抗原，获得可观察的信号是相当困难的。这主要是由于常用的QCM（5至10 MHz石英晶体）缺乏灵敏度。此外，通过 Sauerbrey 方程使用 QCM 响应估计的质量和通过其他分析技术（在我们的例子中为酶测定）可以测量的质量是不同的：QCM 通常高估了沉积的质量。为了验证 QCM 质量测量和抗原识别，在酶吸附到微量天平金电极上或抗体/抗原结合期间研究了声剪切波与生物层的相互作用。在 27 MHz 石英谐振器的谐振频率附近测量电声导纳，与微天平测量并行。将表征石英微天平等效电路的参数与经典微天平频率进行了比较。微量天平给出的质量高估可以通过敏感层流变特性的修改和/或所进行的测定的不足来解释。 (C) 1998 Elsevier Science S.A.
The development of immunosensors based on piezoelectric transducers is widely investigated due to their attractive potentialities. The quartz crystal microbalance (QCM) may give a direct response signal which characterizes the binding event between a sensitive layer, immobilized onto the surface transducer, and the analyte to be detected. However, for small biomolecules, such as some antigens, it is quite difficult to obtain an observable signal. This is mainly due to the lack of sensitivity of the commonly used QCM (5 to 10 MHz quartz crystal). Moreover, the mass estimated with the QCM response through the Sauerbrey equation and the mass which can be measured thanks to other analytical techniques, in our case an enzymatic assay, are different: the deposited mass is generally overestimated by the QCM.To validate QCM mass measurements and, therefore antigens recognition, the interactions of acoustic shear waves with a biolayer were investigated during enzyme adsorption onto the microbalance gold electrode or during the antibody/antigen binding. Electroacoustic admittance was measured around the resonance frequency of a 27 MHz quartz resonator in parallel with microbalance measurements. The parameters which characterize the quartz microbalance equivalent circuit were compared with the classical microbalance frequency. The mass overestimation, given by the microbalance, could be explained either by modification of the rheological properties of the sensitive layers and/or by an inadequacy of the assay performed. (C) 1998 Elsevier Science S.A.