A “turn-on” sensor based on MnO 2 coated UCNPs for detection of alkaline phosphatase and ascorbic acid

and between ΔI and AA concentrations ranging from 0.5 to 250 μM with an LOD of 0.29 μM. The luminescent sensor was also successfully applied for detection of ALP and AA in human serum samples with recoveries from 94.9% to 104.6% and 99.4% to 104.9%.