单扫描极谱法测定注射液及血清中维生素K1

建立了维生素K1的极谱测定方法.在0.05 mol·L-1 NH4Cl-NH3(pH 8.58)缓冲溶液中,维生素K1可产生一极谱还原峰,峰电位Ep为-0.39 V ;其二阶微分峰峰电流ip″与维生素K1的浓度在1.1×10-7 ～2.2×10-5 mol·L-1范围内呈线性关系,相关系数r=0.998 6(n= 9 );方法的检出限为4.0×10-8 mol·L-1.13次平行测定2.2×10-5 mol·L-1维生素K1还原波二阶导数峰峰电流ip″的相对标准偏差(RSD)为1.83%.本法可直接用于注射液及血清中维生素K1含量的测定.

Determination of Vitamin K1 in Injection and Plasma by Signal Sweep Polarography

The 2nd order derivative polarographic method for the determination of vitamin K_(1) in injection and plasma was proposed. In the 0.05 molL~(-1)NH_(4)Cl-NH_(3)(pH 8.58)buffer solution, vitamin K_1 produces a sensitive reduction peak on the dropping mercury electrode at peak potential E_p (-0.39 V, vs.SCE ). The 2nd order derivative polarographic peak current i_(p) of vitamin K_1 is proportional to vitamin K_(1) concentration in the range of 1.110~(-7)~2.2 10~(-5) molL~(-1 )(r=0.998 6 n=9), and its detection limit is 4.010~(-8) molL~(-1). Relative standard deviation (RSD) is 1.83% by performing 13 independent measurements for 2.210~(-5) molL~(-1) vitamin K_(1). The proposed method can be applied to the direct determination of vitamin K_(1) in injections and plasma.