Natural biomass carbon Dots-Based fluorescence sensor for high precision detection of vitamin B12 in serum

Vitamin B12(Vit B12) is an essential micronutrient for body growth, and abnormal levels of Vit B12 in the human body are closely associated with the prediction of certain diseases. Hence, a rapid, sensitive, and environment-friendly approach for Vit B12 detection was set up. Herein, the Bird's nest carbon dots (B-CDs) are synthesized by using a bird's nest and distilled water as precursors. One-step hydrothermal synthesis has created B-CDs without toxic ingredients or surface chemical modifications. The prepared B-CDs exhibited outstanding characteristics including excellent water solubility, brilliant fluorescence performance great biocompatibility, and fine stability in a broad pH range of 3.0-11.0 and high ionic strength solution. The experiment revealed that the fluorescence of the reaction system showed a regular decrease after the interaction of B-CDs with Vit B12. Additionally, there was an excellent linear relationship between the F/F0 of B-CDs and the concentration of Vit B12. The linear range was 0 ∼ 100 µM, R² was 0.9929, and the detection limit was 0.24 µM. Finally, the proposed method successfully detected Vit B12 in human serum samples with recoveries of 96.2 %-100.3 %, showing broad clinical prospects.