Fluorescent sensor array based on Janus silica nanoflakes to realize pattern recognition of multiple aminoglycoside antibiotics and heavy metal ions

The development of highly sensitive and selective chemical sensor arrays that can be used for the recognition of multiple organic and inorganic compounds has been a pressing demand and persistent challenge. We combined the Pickering emulsion and quantum dots (QDs) doping technology to fabricate Janus silica nanoflakes–based fluorescence sensor arrays for the pattern recognition of multiple heavy metal ions and aminoglycoside antibiotics. Janus silica nanoflakes were embedded with green and red light–emitting CdTe QDs as signal sensing units. The aptamer and sulfhydryl-specific recognition elements were modified and attached to the sides for the simultaneous recognition of heavy metal ions and aminoglycosides. The thiol groups chelated the target metal ions, resulting in the fluorescence quenching of the QDs. The aptamers provided specific recognition sites for aminoglycosides, and the fluorescence intensities of the QDs were enhanced in the presence of aminoglycosides. The parameters characterizing the fluorescence sensor array were optimized, and by analyzing the fluorescence response patterns following the linear discriminant analysis method, we observed that the sensor array could discriminate between the target compounds successfully. Finally, Cu2+ and Co2+ were detected in crayfish samples, and the results were confirmed following the inductively coupled plasma atomic emission spectroscopy technique.