a new continuous flow injection analysis method coupled with nag-adf-300-2 analyzer for promethazine-hcl by cadmium iodide as a precipitating reagent

A highly accurate, simple, sensitive turbidimetric method was introduced for the determination of promethazine-hcl using a homemade nag-adf-300-2 system with continuous flow injection analysis system. this method is based on reaction between promethazine-hcl and cadmium iodide (cdi2) in the presence of ammonium acetate to obtain a white precipitate for the ion-pair complex. turbidity was measured via the attenuation of incident light by precipitated at 0-180°. optimum parameters were studied to increase the sensitivity for newly developed methodology of promethazine-hcl- cadmium iodide system. the linear dynamic range for the instrument response vs. concentration of promethazine-hcl- was 0.25-25 mmol. l^-1 for cell a and 0.1-20 mmol.l^-1 for cell b, and limit of quantitative (s/n=10) 360.5574 μg /sample for cell a and 275.5830 μg /sample for cell b respectively with correlation coefficient (r) 0.9961 for cell no. 1 (cell a) and 0.9966 for cell no.2 (cell b); rsd % was lower than 0.6%. a comparison was made between the newly developed method with uv-spectrophotometric and turbidimetric method as a classical method by using the standard addition method via the use of t-test at 95% confidence level. in addition, f-test was utilized to predict which of the methods was more precise than other method. the comparison of data revealed that long distance chasing photometer (nag-adf-300-2) is the choice with excellent extended detection, wide application and more sensitivity.