Sun Wei, Ding Ya-Qin, Rao Jun, Jiao Kui
College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, China.
Guang Pu Xue Yu Guang Pu Fen Xi. 2006 Jul;26(7):1322-5.
The interaction of neutral red and heparin was studied by UV-Vis spectrophotometry in pH 3.0 Britton-Robinson (B-R) buffer solution. Neutral red has a strong absorbance at 523 nm and the addition of heparin into neutral red solution resulted in the decrease in the absorbance value at 523 nm without the appearance of new absorbance peak. The decrease in absorbance value was linear with the concentration of heparin. The conditions for the interaction were optimized and the interferences of coexistent substances were investigated. Under the optimal conditions a linear regression equation was obtained as deltaA = 0.044 + 0.076c (mg x L(-1)) (n = 12, r = 0.997) in the range of 0.10-15.0 mg x L(-1) with the detection limit of 0.073 mg x L(-1). The molar absorptivity of the method was calculated to be 2.037 x 10(6) L x mol(-1) x cm(-1). The method was applied to determine the heparin sodium injection solution with satisfactory results. The stoichiometry of heparin with neutral red was calculated as 1 : 3.
在pH 3.0的 Britton-Robinson（B-R）缓冲溶液中，采用紫外-可见分光光度法研究了中性红与肝素的相互作用。中性红在523 nm处有较强吸收，向中性红溶液中加入肝素后，523 nm处的吸光度值降低，且未出现新的吸收峰。吸光度值的降低与肝素浓度呈线性关系。优化了相互作用条件并研究了共存物质的干扰。在最佳条件下，在0.10 - 15.0 mg·L⁻¹范围内得到线性回归方程为ΔA = 0.044 + 0.076c（mg·L⁻¹）（n = 12，r = 0.997），检测限为0.073 mg·L⁻¹。计算该方法的摩尔吸光系数为2.037×10⁶ L·mol⁻¹·cm⁻¹。该方法用于测定肝素钠注射液，结果令人满意。计算得出肝素与中性红的化学计量比为1 : 3。
