A Fully Integrated Biosensing Platform Combining Acoustofluidics and Electromagnetic Metamaterials

A key challenge in biosensing technology is to develop integrated approaches with the multiple capabilities of bio-sampling, fluid manipulation, high-precision detection and wireless operation. In this work, we present a new concept of integrated biosensing technology using the functionalities of electromagnetic metamaterials and acoustofluidic technology onto a single platform. The new concept of using a single structure to perform microfluidic functions at acoustic frequencies and to detect the characteristics of liquid at microwave frequencies will enable the development of improved lab-on-a-chip devices. As a case study, we demonstrated efficient acoustofluidic functions of mixing and pumping using the designed surface acoustic wave (SAW) device on a LiNbO3 substrate in an experimental setup that also allows the measurement of the electromagnetic characteristics of the interdigitated transducer (IDT) pattern of the same device. We demonstrated microfluidic functions at 10-25 MHz. The device also exhibits electromagnetic resonance at 4.4 GHz with a quality factor value of 294. We showed the device can be used for glucose detection with a
good sensitivity of 28 MHz/(mg/ml).