Quinoline- functionalized Nanoparticles as Luminescent pH-responsive Sensors

The designing of coatings able to sense variations of the environmental conditions (pH, temperature etc) are of interest in “smart” food packaging materials. The response signal of the sensor may often be a distinct visual or emission colour change. Moreover, in many cases, the sensoring unit should be embedded in a polymer matrix, being always in contact with the surrounding environment without showing any significant leakage. Within this frame, in the present work we investigate the potential use of quinoline unit as luminescent pH-responsive sensor, since it is well known that the emitted colour of this unit turns from blue to green as pH decreases and the weakly basic quinoline unit is protonated.

• Copolymers containing the quinoline moiety as a sensoring unit were synthesized through emulsion polymerization providing NPs of 70-100nm diameter
• Optical studies have shown the ability of the developed sensors to be active after incorporation in polymeric matrixes, changing their emitting colour from blue to green when in contact with acidic solutions.