Determination of dihydralazine based on chemiluminescence resonance energy transfer of hollow carbon nanodots.

The famous weak chemiluminescence (CL) system of potassium permanganate and sodium bisulfite (KMnO4 -HSO3 - ) was enhanced by the hollow fluorescent carbon nanodots (HCNs). The investigation of mechanism revealed that the enhanced CL was induced by the excited-state HCNs (HCNs⁎ ), which could be produced from the electron-transfer annihilation of positively charged HCNs (HCNs+ ) and negatively charged HCNs (HCNs- ) as well as by CL resonance energy transfer (CRET) from excited SO2 (SO2 ⁎ )/1 O2 to HCNs. The dihydralazine sulfate (DHZS) had a diminishing effect on the CL of HCNs-KMnO4 -HSO3 - system due to the competitive consumption of O2 - . Under the optimal conditions, the reduced CL signal with the concentration of DHZS was linear in the range of 1.0×10-7 -7.0×10-5 mol/L with a detection limit of 3.0×10-8 mol/L. The relative standard deviation for seven repeated determination of 5.0×10-6 mol/L DHZS was 2.1%. The established method was applied to the determination of DHZS in pharmaceutical preparations, human urine and plasma samples with good precision and accuracy.