Introduction: A novel method for the determination of Ranitidine in flow injection systems was developed.
Methods: Some investigations were also done to find the effects of various parameters on the sensitivity of the method. The conditions producing optimal performance were a pH value of 2, a scan rate value of 100 V/s, accumulation potential of (-100) mV, and accumulation time of 0.4 s. Some of the advantages of the proposed method are as follows: the removal of oxygen from the test solution is not required any more, the detection limit of the method is sub-nanomolar and finally, the method is fast enough for determination of compounds in a wide variety of chromatographic methods. We also introduce a special computer based numerical method, for calculation of the analyte signal and noise reduction. After subtracting the background current from noise, the electrode response was calculated, based on partial and total charge exchanges at the electrode surface. The integration range of currents was set for all the potential scan ranges, including oxidation and reduction of the Au surface electrode, to obtain a sensitive determination. The waveform potential was continuously applied on an Au disk microelectrode (12.5 microm in radius).
Results: The detection limit of the method for Ranitidine was found to be 25 pg/ml. For 8 runs, the relative standard deviation of the method at 1.1 x 10(-8) M was 2.1%.
Discussion: The method was successfully applied for fast determination of Ranitidine in its pharmaceutical formulations. Being very simple, precise, accurate, time saving and economical this method has many advantages compared to all previously reported methods.