Platform for resonant chemical and biosensors based on phononic crystals

本课题的目标是开发一个化学和生物传感器的传感器平台，以满足微流体系统对传感器的需求。它结合了5个特点：-液相传感器-传感器监测化学和生化过程在自由体积和生理环境-样品体积低于1 μ l-坚固，测量领域的纯声学原理-传感器与微力学/微流体的集成测量原理具有经典谐振原理无法实现的两个独特特征：-测量被测分析物的体积值，声速和声衰减-测量值与被分析物的分子性质之间的直接关系以及各成分之间的相互作用在液体分析和生物物理研究中的应用。提出的示范是医疗技术领域的血糖原位测量和生物柴油生产领域的生物甘油氢解制1,2-丙二醇分析。传感器的工作原理是基于超声光谱学中应用的效应。它利用了缺陷的谐振特性，同时作为微流体系统的测量单元，目的是将其引入声子晶体。声子晶体的设计和尺寸考虑了传感器灵敏度、微流体系统的典型尺寸和分析物的总体粘度方面的要求和规格。传感器的转导方案包括两个步骤：1.传感器的转导方案；由于被分析物的特定（生物）化学反应、被分析物的特定（生物）物理性质变化或测量池中混合物的特定组分的浓度变化而引起的声波速度和声波衰减的物质特异性变化。由于声速的变化和超声波的衰减而引起的共振频率的不特定移动和共振峰值幅度的变化。传感器平台的设计、优化和技术实现是本项目的主要任务，考虑到高灵敏度和高可靠性是化学或生物传感器前景应用的基本要求。这项工作的价值将是设计一个合适的声子晶体，包括一个具有所需传感能力的液相，应用两个演示，确认和优化体积传感器效应，为压电基板开发合适的微机械技术，并确定选定分析物在超声波频率下的声学特性以及与用户感兴趣值的相关性。

The objective of the proposal is the development of a sensor platform for chemical and biosensors satisfying the demand on sensors for microfluidic systems. It combines 5 features:- sensor for liquid phase- sensor for monitoring chemical and biochemical processes in free volume and physiological environment- sample volumes below 1 µl- robust, pure acoustic principle in area of measurement- integration of sensor and micromechanics/microfluidicsThe measurement principle has two unique features not achievable with classical resonant principles:- measurement of the volumetric values speed of sound and sound attenuation of the analyte under inspection- direct relation between measurement values and molecular properties of the analyte and interaction between the constituentsThe development of the sensor platform therefore points to applications in liquid analysis and biophysical studies. The proposed demonstrators are the in-situ measurement of blood glucose in the field of medical technology and the anaylsis of hydrogenolysis of bio-glycerol to 1,2-propanediol in the field of bio diesel production. The sensor principle is based on effects applied in ultrasonic spectroscopy. It takes advantage of resonant features of a defect, simultaneous being the measurement cell of the microfluidic system, introduced to a phononic crystal by purpose. Design and dimensions of the phononic crystal consider the requirements and specifications with respect to sensor sensitivity, typical dimensions of microfluidic systems, and bulk viscosity of the analyte. The transduction scheme of the sensor consists of 2 steps:1. the material specific variation of speed of sound and sound attenuation of the ultrasonic wave traveling through the analyte caused by a specific (bio)chemical reaction, a specific (bio)physical property change of the analyte or a change in concentration of a specific component of the mixture in the measurement cell2. the unspecific shift of the resonance frequency and change in resonance peak amplitude as a result of a change in speed of sound and attenuation of the ultrasonic wave. Design, its optimization and technological realization of the sensor platform are the major tasks of the project, considering high sensitivity and reliability as fundamental requirement for the prospective applications as chemo- or biosensor. The value of the work will be the design of an appropriate phononic crystal including a liquid phase with the required sensing capabilities applying two demonstrators, confirmation and optimization of the volumetric sensor effect, the development of an appropriate micromechanical technology for piezoelectric substrates and the determination of acoustic properties of selected analytes at ultrasonic frequencies and correlation to values of users interest.