Development of the fluorescent carbon nanosensor for pH and temperature of liquid media with artificial neural networks.

The present study is devoted to the creation of optical nanosensors for pH and temperature of liquid media based on carbon dots (CD) prepared via hydrothermal synthesis. The application of artificial neural networks to the CD fluorescence spectra database provided simultaneous determination of pH and ambient temperature values with an accuracy of 0.005 pH units and 0.67 °C, respectively. The obtained results are unique since they indicate the possibility of creating a multifunctional CD-based nanosensor that operates in a wide temperature range (22-81 °C) and provides an accuracy of pH determination exceeding the accuracy of nanoscale analogs by an order of magnitude.