Flexible SAW Microfluidic Devices as Wearable pH Sensors Based on ZnO Nanoparticles

Nanomaterials

Francesco Guido¹  Massimo De Vittorio¹  Luigi Piro¹  Massimo Mariello¹  Antonio Balena¹  Francesco Rizzi¹  Leonardo Lamanna² 

[1] Center for Biomolecular Nanotechnologies, Istituto Italiano di Tecnologia, 73010 Arnesano, Italy;Center for Nano Science and Technology, Istituto Italiano di Tecnologia, 20133 Milan, Italy;

关键词: SAW;    wearable device;    flexible;    biosensor;    PEN;    pH ZnO nanoparticles;   

DOI  :  10.3390/nano11061479

来源: DOAJ

【 摘 要 】

In this work, a new flexible and biocompatible microfluidic pH sensor based on surface acoustic waves (SAWs) is presented. The device consists of polyethylene naphthalate (PEN) as a flexible substrate on which aluminum nitride (AlN) has been deposited as a piezoelectric material. The fabrication of suitable interdigitated transducers (IDTs) generates Lamb waves (L-SAW) with a center frequency ≈500 MHz traveling in the active region. A SU-8 microfluidics employing ZnO nanoparticles (NPs) functionalization as a pH-sensitive layer is fabricated between the IDTs, causing a shift in the L-SAW resonance frequency as a function of the change in pH values. The obtained sensitivity of ≈30 kHz/pH from pH 7 to pH 2 demonstrates the high potential of flexible SAW devices to be used in the measurement of pH in fluids and biosensing.

【 授权许可】

Unknown