APPARATUS AND METHODS FOR DETERMINING THE VISCOELASTIC PROPERTIES OF MATERIALS

摘要

The present invention relates to apparatus and methods for determining the viscoelastic (rheologic) properties of materials. The apparatus and methods of the present invention are particularly advantageous for determining the viscoelastic properties of extracellular matrices (ECMs) that are becoming increasingly important for accurate predictive modeling of biological systems.In one aspect the present invention provides a piezoelectrically actuated linear rheometer (PALR) designed to remedy the problems currently associated with rheometric methods when measuring the surface and bulk viscoelastic properties of hydrated materials. The novel apparatus comprises a cantilever that applies an oscillating load to the viscoelastic material in order to sense the material's deflection. Comprising a plurality of piezopolymer layers, the cantilever uses one layer as an actuator and another piezopolymer layer to measure the lateral movement of an attached probe. The viscoelastic nature of the test material adds damping to the system, resulting in the attenuation and phase shift of the sensor's output voltage. From these parameters, physical properties of a material, such as shear storage and loss modulus, may be quantified.