Eye-Readable and Wearable Colorimetric Sensor Arrays for In Situ Monitoring of Volatile Organic Compounds.
Zhiheng YouMingming ZhaoHuizi LuHuayun ChenYixian WangPublished in: ACS applied materials & interfaces (2024)
Wearable sensors utilize changes in color as a response to physiological stimuli, making them easily recognizable by the naked eye. These colorimetric wearable sensors offer benefits such as easy readability, rapid responsiveness, cost-effectiveness, and straightforward manufacturing techniques. However, their applications in detecting volatile organic compounds (VOCs) in situ have been limited due to the low concentration of complex VOCs and complicated external interferences. Aiming to address these challenges, we introduced readable and wearable colorimetric sensing arrays with a microchannel structure and highly gas-sensitive materials for in situ detection of complex VOCs. The highly gas-sensitive materials were designed by loading gas-sensitive dyes into the porous metal-organic frameworks and further depositing the composites on the electrospun nanofiber membrane. The colorimetric sensor arrays were fabricated using various gas-sensitive composites, including eight dye/MOF composites that respond to various VOCs and two Pd 2+ /dye/MOF composites that respond to ethylene. This enables the specific recognition of multiple characteristic VOCs. A microfluidic channel made of polydimethylsiloxane (PDMS) was integrated with different colorimetric elements to create a wearable sensor array. It was attached to the surface of fruits to collect and monitor VOCs using the DenseNet classification method. As a proof of concept, we demonstrated the feasibility of the wearable sensing system in monitoring the ripening process of fruits by continuously measuring the VOC emissions from the skin of the fruit.
Keyphrases
- aqueous solution
- gold nanoparticles
- metal organic framework
- reduced graphene oxide
- heart rate
- hydrogen peroxide
- sensitive detection
- fluorescent probe
- room temperature
- living cells
- high density
- label free
- loop mediated isothermal amplification
- visible light
- nitric oxide
- blood pressure
- deep learning
- carbon dioxide
- highly efficient
- high throughput
- healthcare
- mass spectrometry
- single cell
- high resolution
- heavy metals
- wound healing