Fig. 2. (a) PL intensity of CDs in the absence (black) and presence (red) of 15 μM VB12 in BR buffer solution of various pHs; (b) PL intensity of CDs in the absence (black) and presence (red) of 15 μM VB12 in different buffer solutions; (c) time-dependent fluorescence intensity of CDs to 15 μM VB12; (d) effect of CDs concentration on fluorescence quenching.
