Hermetically Packaged Microsensor for Quality Factor-Enhanced Photoacoustic Biosensing

Photoacoustics. 2020 May 16:18:100189. doi: 10.1016/j.pacs.2020.100189. eCollection 2020 Jun.

Abstract

The use of photoacoustics (PA) being a convenient non-invasive analysis tool is widespread in various biomedical fields. Despite significant advances in traditional PA cell systems, detection platforms capable of providing high signal-to-noise ratios and steady operation are yet to be developed for practical micro/nano biosensing applications. Microfabricated transducers offer orders of magnitude higher quality factors and greatly enhanced performance in extremely miniature dimensions that is unattainable with large-scale PA cells. In this work we exploit these attractive attributes of microfabrication technology and describe the first implementation of a vacuum-packaged microscale resonator in photoacoustic biosensing. Steady operation of this functional approach is demonstrated by detecting the minuscule PA signals from the variations of trace amounts of glucose in gelatin-based synthetic tissues. These results demonstrate the potential of the novel approach to broad photoacoustic applications, spanning from micro-biosensing modules to the analysis of solid and liquid analytes of interest in condense mediums.

Keywords: Biosensing; Micromechanical resonator; Photoacoustics; Quality factor; Vacuum-packaged.