铜-1-(2-吡啶偶氮)-2-萘酚体系的极谱吸附催化波研究及应用

Adsorptive Catalytic Polarographic Wave of Copper(Ⅱ)-1-(2-Pyridylazo)-2-naphthol in the Presence of Potassium Persulfate and Its Application

在KH2PO4NaOH(pH=6.4)缓冲溶液中,Cu(Ⅱ)1(2吡啶偶氮)2萘酚(PAN)在-0.23V(vs.SCE)产生灵敏的络合吸附波。加入了过硫酸钾以后,波高进一步增加,二阶导数峰电流与1.5×10-8～6.0×10-6mol/LCu2+呈良好的线性关系;检出限为8.0×10-9mol/L。研究了极谱波的性质及增敏的机理,表明该极谱波为吸附催化波。用于大米、绿豆和人发中铜含量的测定,取得了满意的结果。

In KH_2PO_4-NaOH phosphate buffer (pH= 6.4), copper(Ⅱ) reacts with 1-(2-pyridylazo-2-naphthol (PAN) to form a complex which appears a sharp polarographic wave at-0.23V(vs.SCE) . When K_2S_2O_8 was added, the peak height was increased. The second derivative current (i″_p) is linear with the concentration of copper(Ⅱ) in the range of 1.5×10^-8 ～6×10^-6 mol/L with detection limit of 8.0×10^-9 ~mol/L . The character of polarographic wave was studied, and results show that this wave is an adsorptive catalytic wave. The method has been applied to determine copper(Ⅱ)in rice, mung bean and human hair, the results are satisfied.