Highly effective volatile organic compound dissolving strategy based on mist atomization for odorant biosensors

Abstract

The detection of volatile organic compound (VOC) mixtures is crucial in the medical and security fields. Receptor-based odorant biosensors sensitively and selectively detect odorant molecules in a solution; however, odorant molecules generally exist as VOCs in the air and exhibit poor water solubility. Therefore, techniques that enable the dissolution of poorly water-soluble VOCs using portable systems are essential for practical biosensors' applications. We previously proposed a VOC dissolution method based on water atomization to increase the surface area via the generation of fine bubbles, as a proof-of-concept; however, the system was lab-based (non-mobile) and the dissolution was limited to one VOC. In this study, we established a highly effective VOC dissolution method based on mist atomization that can be used in the field. This new method demonstrated a rapid dissolution potential of a sparsely-soluble VOC mixture with various functional groups in distilled water (DW) within 1 min, without the use of any organic solvents. Calcium imaging revealed that odorant receptor 13a-expressing Sf21 cells (Or13a cells) responded to 1-octen-3-ol in the mixture. Further, we successfully developed a field-deployable prototype vacuum and dissolution system with a simple configuration that efficiently captured and rapidly dissolved airborne 1-octen-3-ol in DW. This study proposes a field-deployable system that is appropriate for solubilizing various airborne odorant molecules and therefore is a practical strategy to use in the context of odorant biosensors.

Keywords: Fine bubble; Insect cell; Odorant biosensor; Odorant receptor; Ultrasonic spray; Volatile organic compound.