Fluorescent sensor array for tetracyclines discrimination using a single Dye@MOF composite sensor

The incorporation of multiple sensing elements to a single sensor has been proposed by our group as an improvement for the array sensing technique with retaining the high selectivity of traditional multi-sensor based sensor array but largely simplifying the analytical operation. How to select reasonable sensing elements to construct the sensor is the key to improve the analytical performance. Herein, we propose a concept to solve this issue, that is, using the components which test different properties of analytes to discriminate them from various aspects. As a proof-of-principle trial, a MOF based composite sensor was designed to analyze tetracycline type antibiotics. The porphyrin-containing main ligand, naphthyl auxiliary ligand and rhodamine B guest were installed to response to the redox property, adsorption affinity and absorption/exchanging capability of the analyte, respectively. Six tetracycline homologous were clearly identified by this sensor, and it also exhibited good quantification performance. This method was successfully applied to the analysis of practical milk sample. [Display omitted] •A MOF based composite was designed as a tri-channel fluorescent sensor.•Three components of the sensor response to different analyte properties.•With this sensor, a single sensor based sensor array was developed.•It can identify six tetracycline homologous even with unknown concentrations.•This method was successfully applied to practical food analysis.