中文摘要：

在pH6．0的Britton—Robinson（B-R）缓冲溶液中，用循环伏安法研究了中性红（NR）与肝素（Hep）的相互作用。在最佳实验条件下，NR与Hep通过静电作用形成复合物，导致溶液的还原峰电流明显降低，其峰电流差值（△ip）与Hep的浓度成正比，据此建立了一种测定Hep浓度的新方法，测定的线性范围为2～20μg／mL，相关系数r=0．9983，检测限（3σ）为1．05μg／mL。该法应用于注射液中肝素舍量的测定，结果满意。

英文摘要：

The interaction between neutral red （NR） and heparin （Hep） was studied by cyclic voltammetry in pH 6.0 Britton-Robinson buffer solution. Under the optimum conditions, NR reacted with Hep to form a complex compound by virtue of electrostatic force, which resulted in a significant decrease of the reduction peak current. The difference in peak currents （△ip） was proportional to the concentration of Hep. Based on this a new method for the determination of Hep concentration was established. The linear range for the determination of Hep was 2.0-20.0 μg/mL with a correlation coefficient of 0. 998 3, and the determination limit was 1.05μg/mL. The method was applied to the determination of Hep in drug samples with satisfactory results.