Determination of mangiferin via a smartphone-assisted fluorescence system with blue-emitting carbon quantum dots

Mangiferin is beneficial to human health. However, excessive use can cause side effects. Herein, we fabricated a hydrothermal strategy for the development of blue-emissive fluorescence carbon quantum dots (BCQDs) for the measurement of mangiferin. An excellent fluorescence emission signal around 468.7 nm was observed at the excitation wavelength of 363.4 nm. Some amazing features for BCQDs could be observed, such as exceptional stability, radiation resistance, salt resistance, and water solubility. The BCQDs displayed a specific response for mangiferin, leading to fluorescence weakening in a linear range of 0.5–100 μM. And the detection limit was 0.061 μM. The fluorescence quenching mechanism was assigned to the inner filter effect. Furthermore, two different real samples were sensitively determined to mangiferin using this as-prepared BCQDs-based nanosensor, generating satisfactory results with recoveries of 94.8–104.8 %. Notably, the apparent color variation from blue to green in the presence of mangiferin suggested smartphone-based visual inspection, indicating emphatic potential for on-site sensing. Moreover, the BCQDs-based sensing system had exceptional greenness and blueness.