以复红为探针建立了快速测定药物中盐酸米多君的高灵敏双波长共振瑞利散射（RRS）法。在pH 3.46的酸性溶液中，复红与十六烷基溴化吡啶鎓及盐酸米多君作用生成三元离子缔合物，使RRS信号显著增强并产生具有双峰的新的RRS光谱。最大RRS峰位于620 nm，次大RRS峰位于370 nm，在此二波长处的RRS增强强度与0.009~0.35 mg/L盐酸米多君的质量浓度呈线性关系，检出限分别为0.006 2 mg/L （370 nm）和0.005 8 mg/L （620 nm），当用双波长叠加RRS法测定时，检出限为0.003 0 mg/L。还研究了三元缔合反应的适宜条件、共存物质的影响及双波长RRS法的光谱特征。该方法可用于市售盐酸米多君药片中盐酸米多君含量的测定，回收率和相对标准偏差RSD%（n=5）分别为98.3%~102%和1.2%~1.8%。

A new highly sensitive dual-wavelength resonance Rayleigh scattering (RRS) method for rapid determination of midodrine hydrochloride in drugs is established with fuchsin as probe.In an acidic solution of pH 3.46,fuchsin reacts with 1-hexadecylpyridinium bromide and midodrine hydrochloride to form a ternary ion association complex,which leads to a greatly enhanced resonance Rayleigh scattering (RRS) signal of system and produces a new RRS spectrum with double peaks.The largest RRS peak locates at 620 nm and the second largest RRS peak locates at 370 nm.At these two wavelengths,RRS enhanced intensity (ΔI_RRS) is directly proportional to the mass concentration of midodrine hydrochloride in the range of 0.009 to 0.35 mg·L^-1.The detection limits are 0.006 2 mg·L^-1 (for 370 nm peak) and 0.005 8 mg·L^-1 (for 620 nm peak),respectively.When dual-wavelength superposition RRS method is used to determine the concentrations of midodrine hydrochloride,the detection limit is 0.003 0 mg·L^-1.The suitable conditions for the ternary association reaction,the influence of coexisting substances and the spectral characteristics of dual-wavelength RRS method are also studied.This method can be applied to the determination content of midodrine hydrochloride in commercially available midodrine hydrochloride tablets with the recoveries in the range of 98.3% to 102% and RSD% (n=5) between 1.2% and 1.8%.

赵燕(1995-),女,本科,研究方向为分子光谱分析,zhaoyan20152017@163.com