Biosensor for human IgE detection using shear-mode FBAR devices

Abstract

Film bulk acoustic resonators (FBARs) have been evaluated for use as biosensors because of their high sensitivity and small size. This study fabricated a novel human IgE biosensor using shear-mode FBAR devices with c-axis 23°-tilted AlN thin films. Off-axis radio frequency (RF) magnetron sputtering method was used for deposition of c-axis 23°-tilted AlN thin films. The deposition parameters were adopted as working pressure of 5 mTorr, substrate temperature of 300°C, sputtering power of 250 W, and 50 mm distance between off-axis and on-axis. The characteristics of the AlN thin films were investigated by X-ray diffraction and scanning electron microscopy. The frequency response was measured with an HP8720 network analyzer with a CASCADE probe station. The X-ray diffraction revealed (002) preferred wurtzite structure, and the cross-sectional image showed columnar structure with 23°-tilted AlN thin films. In the biosensor, an Au/Cr layer in the FBAR backside cavity was used as the detection layer and the Au surface was modified using self-assembly monolayers (SAMs) method. Then, the antigen and antibody were coated on biosensor through their high specificity property. Finally, the shear-mode FBAR device with kt2 of 3.18% was obtained, and the average sensitivity for human IgE detection of about 1.425 × 105 cm2/g was achieved.

Mechanical, Corrosion and Biological Properties of Room-Temperature Sputtered Aluminum Nitride Films with Dissimilar Nanostructure

“…Also, AlN is seen a very promising material for realization of various microfluidic and biosensing applications, with integrated lab-on-chip diagnostic systems being envisaged [ 30 ]. For instance, AlN thin-film bulk acoustic resonator (FBAR) devices have been used to detect carcinoembryonic antigen (cEA) [ 31 ], or human immunoglobulin E (IgE) antibody [ 32 ]. Furthermore, a AlN/diamond based FBAR for biomedical applications was endeavored [ 33 ], whilst other researchers suggest the great promise of AlN thin films for biosensing of cell differentiation [ 34 ].…”

An Overview of High Frequency Acoustic Sensors—QCMs, SAWs and FBARs—Chemical and Biochemical Applications

“…There is a wide variety of receptor coatings that can be combined with acoustic devices for developing highly sensitive sensors. These receptors may range from natural antibodies [34,35,36,37], aptamers [38,39,40,41], DNA [42,43,44,45], protein/peptides [46,47,48,49] to synthetic affinity materials including functionalized polymeric layers [50,51,52,53], nanoparticles [54,55,56,57], carbon nanotubes [58,59,60,61], graphene oxide [62,63,64,65] and many others. As a result, the sensing domain of acoustic devices is significantly large which covers the detection of diverse bio-analytes such as bacteria [66,67], viruses [68,69] and whole cells [70,71,72,73], recognition of clinical biomarkers in complex samples [74,75,76], food analysis [77,78], process control and monitoring of environmental toxins [79] in liquid and gaseous phases.…”

Label-free sensitive detection of influenza virus using PZT discs with a synthetic sialylglycopolymer receptor layer

“…Currently, numerous publications describe the potential of using MEMS for virus detection by surface acoustic waves resonators (SAW) [8,24], a capacitive micromachined ultrasound transducer (cMUT) [25], a quartz crystal microbalance (QCM) [10,11,26,27] and a film bulk acoustic resonator (FBAR) [16,28]. Terahertz biosensing metamaterials methods [29,30] have a very high virus detection sensitivity and could potentially be used in the future for home appliance devices, but they currently have many issues regarding selectivity in highly contaminated air with other particles with different dielectric constants and the embodiment of this technology in home appliance devices.…”