Experimental design optimization of a sequential injection method for promazine assay in bulk and pharmaceutical formulations

• Published in: Journal of automated methods & management in chemistry 2007, Vol.2007, p.32470-32470
• Main Authors: Idris, Abubakr M, Assubaie, Fahad N, Sultan, Salah M
• Format: Article
• Language: English
• Subjects: Drugs; Injections; Mathematical optimization; Sequential analysis
• ISSN: 1463-9246; 1464-5068
• DOI: 10.1155/2007/32470

Experimental design optimization approach was utilized to develop a sequential injection analysis (SIA) method for promazine assay in bulk and pharmaceutical formulations. The method was based on the oxidation of promazine by Ce(IV) in sulfuric acidic media resulting in a spectrophotometrically detectable species at 512 nm. A 3(3) full factorial design and response surface methods were applied to optimize experimental conditions potentially controlling the analysis. The optimum conditions obtained were 1.0 x 10(-4) M sulphuric acid, 0.01 M Ce(IV), and 10 muL/s flow rate. Good analytical parameters were obtained including range of linearity 1-150 mug/mL, linearity with correlation coefficient 0.9997, accuracy with mean recovery 98.2%, repeatability with RSD 1.4% (n = 7 consequent injections), intermediate precision with RSD 2.1% (n = 5 runs over a week), limits of detection 0.34 mug/mL, limits of quantification 0.93 mug/mL, and sampling frequency 23 samples/h. The obtained results were realized by the British Pharmacopoeia method and comparable results were obtained. The provided SIA method enjoys the advantages of the technique with respect to rapidity, reagent/sample saving, and safety in solution handling and to the environment.