在弱碱性的多聚磷酸钠介质中,二价铜离子、过氧化氢和染料罗丹明B混合可以产生较强的化学发光,法莫替丁对此发光有较强的抑制作用,据此并结合流动注射技术,提出一种直接测定法莫替丁的化学发光方法.其抑制发光强度与法莫替丁的质量浓度在5~ 1 000 μg·L-1范围内呈线性关系,检出限为2.7 μg·L-1(S/N=3),对300 μg·L-1法莫替丁平行测定11次,其相对标准偏差为2.1%.该方法已用于针剂和片剂中法莫替丁含量的测定,并测得方法的回收率在99.5%~102.8%之间,对方法的化学机理也作了简要探讨.

In a weakly allkaline medium of sodium polyphosphate of pH 8.68,chemiluminescence (CL),produced by the reaction among cupric ion,hydrogen peroxide and rhodamine B was strongly inhibited by the drug,famotidine.By applying the flow injection technique,a method of determination of famotidine by CL was proposed.Magnitude of CL intensity inhibited was found to keep linear relationship with the concentration of famotidine in the range of 5.0-1 000 μg·L-1 with a detection limit (as defined by IUPAC) of 2.7 μg·L-1.Precision of the method was tested at the concentration level of 300 μg·L-1 for 11 determinations,giving value of RSD 2.1%.The proposed method was applied to the analysis of famotidine injection and tablet samples,giving values of recovery in the range of 99.5% to 102.8%.The chemism of the CL-inhibition process was also discussed briefly.