An optical-nose device based on fluorescent nanomaterials sensor array for authentication of saffron

This paper presents the development of an optical-nose (o-nose) fluorescence sensor array for the authentication of saffron. The sensor array, which consists of fluorescence sensors made from chemically modified metallic nanoclusters and carbon dots of various functional groups, sniffs the odor emitted from saffron and other possible adulterant herbs and accordingly produces differential fluorescence patterns for different herbs. According to the difference in the chemical composition of the herbs’ aroma, the device was able to differentiate saffron from other herbs and pure saffron from its mixtures with other herbs. The device produces a multi-dimensional response vector and hence it needs to be processed by multivariate data analysis methods. Classification modeling by linear discriminant analysis, principal component-discriminant analysis and partial least squares discriminate analysis were successfully utilized to model the sensor data and accurate discriminate models were produced. Additionally, the method was able to differentiate between four different organs of saffron which differ in quality. The results of this study demonstrate the potential of o-nose fluorescence sensor arrays for the rapid and reliable authentication of saffron.