关键词: 纳米金；计时库仑法；氯化六氨合钌；PML/RAR&alpha, 融合基因

Abstract: potential. The sulfydryl modified probe was immobilized onto surface of gold nanoparticles via Au-S covalent bond and hybridized with complementary target DNA sequences, then the DNA sensor was fabricated for the detection of PML/RARα fusion gene by chronocoulometry in acute promyelocytic leukemia (APL). Scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS) were used to characterize the surface morphology of gold nanoparticles and the constructing process of sensor. With hexaammineruthenium(Ⅲ) chloride (RuHex) as a novel electrochemical indicator, the chronocoulometric DNA biosensor was employed to monitor artificial APL PML/RARα fusion gene fragment．Experimental results showed that the gold nanoparticles amplified the detection signal of RuHex. The linear relationship between the charge difference in the RuHex after and before hybridization and logarithmic concentrations (log C) of target sequence was observed in the concentration range of 1.0×10-13 ~ 1.0×10-9 mol?L-1, and the detection limit had been estimated to be 3.7×10-14 mol?L-1 (S/N=3). This approach is simple, has good specificity, and is promising to apply for the detection of APL in the real sample for medical diagnostics.

Key words: gold nanoparticles, chronocoulometric, RuHex, PML/RAR&alpha, fusion gene