Fluorescence probe method for determination of ranitidine,nizatidine and cimetidine

Objective:To establish a new method for determination of ranitidine,nizatidine and cimetidine by using sensitive fluorescence probe.Methods:CB[7] could react with berberine to form a stable complex,and the fluorescence intensity of the complex was greatly enhanced.Ranitidine,nizatidine and cimetidine can dramatically quench the fluorescence intensity of the complex.Accordingly,a new fluorescence quenching method was established for the determination of these three histamine H2 receptor antagonists.Results:There was a good linear relationship between fluorescence quenching values(ΔF) and a certain concentration range of medicament concentration.The minimal detection limits of ranitidine,nizatidine and cimetidine respectively was 0.007,0.007 and 0.020 μg·mL-1,respectively,which was 2 orders of magnitude higher than normal spectroscopic method.Pharmaceutical preparations and spiked urine samples were also determined and satisfactory recoveries were obtained.Conclusion:The method can be applied to determination of ranitidine,nizatidine and cimetidine in both pharmaceutical samples and urine samples.