An absolutely green approach to fabricate carbon nanodots from soya bean grounds

In this work, we report a simple and thoroughly green approach to prepare photoluminescent carbon nanodots (C-dots) using soya bean grounds as a carbon source without any chemical additives. The obtained C-dots with an average diameter of 3.0 nm or so exhibited excellent biocompatibility and typically multicolor fluorescence. The practicality of C-dots for NIH3T3 cells imaging was validated, and NIH3T3 cells treated with C-dots became bright and showed different colors under different excitation wavelength.