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• • A colorimetric sensor array based on peroxidase activity nanoenzymes was constructed. • • Eight tea polyphenols in Tieguanyin were successfully distinguished. • • Effective identification of Tieguanyin and adulterated tea. • • Effectively identify Tieguanyin of different harvesting seasons. • • Successfully identified autumn tea with different degrees of adulteration. Tieguanyin (TGY) is one of top ten famous teas in China, but in the process of brand building there is the phenomenon of falsehood, thus harming the interests of consumers. To solve the adulterate problem of TGY, a colorimetric sensor array (CSA) based on peroxidase activity of nanozyme was constructed. Nanozymes can catalyze 3,3′,5,5′-tetramethylbenzidine (TMB) to 3,3′,5,5′-tetramethyl -[1,1′-bis(cyclohexyl)]-2,2′,5,5′-tetraene-4,4′-diimine (oxTMB), while the tea polyphenols (TPs) can inhibit this process, and the degree of inhibition varies significantly with the reaction time. We selected two nanozymes and three reaction time points to construct CSA. It can successfully distinguish TPs in TGY. The discriminative analysis can achieve: (1) distinction between TGY and adulterated tea, (2) discrimination of TGY in various seasons and seasonal adulteration in different degrees. The method constructed in this work is promising for both the class and quality differentiation of TGY and other teas with TPs as the main activity. [ABSTRACT FROM AUTHOR]

• A novel sensor array is developed for the identification of milk adulteration. • The sensor array is based on perylene probe monomer-excimer emission transition. • Cationic polymer induced aggregation of a perylene probe. • The sensor array can be applied for the quantification of milk adulteration. A novel fluorescence sensor array based on cationic polymer induced self-assembly of a perylene probe is developed. Cationic polymer induced aggregation of the carboxyl modified negatively charged perylene probe, and resulted in large quenching of monomer emission and generation of excimer emission. Upon the addition of negatively charged protein, monomer fluorescence restored with a decrease in excimer fluorescence. Based on these observations, we developed a six-channel sensor array to discriminate five main proteins in milk. In addition, we successfully identified pure milk out of different drinks using the developed sensor array since different drinks contained distinct species and contents of proteins. Furthermore, the sensor array exhibited excellent performance to discriminate milk adulterated by different concentrations of adulterants with 100% accuracy of cross validation. The analysis results also presented excellent linear correlation of adulterants contents and thus the developed sensor array shows great potential for quantitative detection of milk adulteration. [ABSTRACT FROM AUTHOR]