Carbon dots-decorated hydroxyapatite nanowires-lanthanide metal-organic framework composites as fluorescent sensors for the detection of dopamine.

In this work, carbon dots-decorated hydroxyapatite nanowires-lanthanide metal-organic framework composites were designed and synthesized as ratiometric fluorescent probes for the detection of dopamine. The as-prepared HAPNWs-CDs-Tb/MOF were characterized by TEM, FE-SEM, and FT-IR spectral analysis, illustrating that the HAPNWs-CDs-Tb/MOF comprised hydroxyapatite nanowires that acted as a carrier to form a spinning structure of the lanthanide MOF that was decorated with carbon dots. The as-prepared HAPNWs-CDs-Tb/MOF were luminescent with the green fluorescence of Tb3+ at 543 nm and the blue fluorescence of the CDs at 426 nm as the signal response groups for the detection of DA. The sensor could detect DA in the concentration range of 0-180 µM, with a linear range of 0.04-20 µM and detection limit of 12.26 nM. The method was successfully applied to the detection of DA in human serum. The spiked recoveries were 100.8%-103.3% and the relative standard deviation (RSD) was 3.82%.