Carbon dot based colorimetric sensor array for discrimination of different waters
Herein, a colorimetric sensor array has been introduced which uses carbon dots (CDs) to distinguish between different water samples. The basis of this method is that, CDs interact differently with heavy metal ions in the presence of different water samples. The color change resulting from this interaction is recorded by the digital camera and the RGB values are analyzed by unsupervised and supervised chemometrics methods of hierarchical cluster analysis (HCA), principal component analysis (PCA) and linear discriminant analysis (LDA). For increasing the variables in the designed array, instead of using different CDs, interaction of a single CD with different heavy metal ions and in different concentration levels is employed. Efficiency of the colorimetric sensor array to discriminate between deionized water and three real water samples was excellent. In addition to efficiency, designed colorimetric sensor array is simple and inexpensive.