A novel olfactory biosensor based on ZIF-8@SWCNT integrated with nanosome-AuNPs/Prussian blue for sensitive detection of hexanal

Hexanal is considered as an important volatile compound indicator for the assessment of freshness and maturity of foods. Therefore, sensitive and stable monitoring of hexanal is highly desired. Herein, an efficient receptor immobilization strategy based on ZIF-8@ Single-walled carbon nanotube (SWCNT) and nanosomes-AuNPs/Prussian blue (PB) was proposed for the development of olfactory biosensors. ZIF-8@SWCNT as dual support materials provided a high density of active sites for nanosomes loading. Moreover, the co-electrodeposition of nanosomes-AuNPs and PB on the sensor interface effectively amplified the electrochemical signal and maintained the activity of the receptor. The combination of ZIF-8@SWCNT with AuNPs/PB imparts excellent sensing performance of the biosensor with a wide detection range of 10 −16 –10 −9  M, a low detection limit of 10 −16  M for hexanal, and a long storage stability of 15 days. These results indicate that our biosensor can be a powerful tool for versatile applications in food and other related industries.