Abstract
A simple RP-HPLC method has been developed for simultaneous estimation of fexofenadine and pseudoephedrine in their extended release tablet. The method was developed based on statistical design of experiments (DoE) and Response Surface Methodology. Separation was achieved on double end-capped C18 column (250 mm × 4 mm, 5 μm). In this experiment, two components of mobile phase, namely, acetonitrile (% v/v) and methanol (% v/v), were the factors whereas retention and resolution of the chromatographic peaks were the responses. The effects of different composition of factors on the corresponding responses were investigated. The optimum chromatographic condition for the current case was found as an isocratic mobile phase consisting of 20 mM phosphate buffer (pH 6.8) and acetonitrile and methanol in a ratio of 50 : 36 : 14 (% v/v) at a flow rate of 1 mL/min for 7 minutes. The retention of pseudoephedrine and fexofenadine was found to be 2.6 min and 4.7 min, respectively. The method was validated according to the ICH and FDA guidelines and various validation parameters were determined. Also, forced degradation studies in acid, base, oxidation, and reduction media and in thermal condition were performed to establish specificity and stability-indicating property of this method. Practical applicability of this method was checked in extended release tablets available in Bangladeshi market.
Highlights
Fexofenadine hydrochloride (FEX) is a nonsedating antihistamine which works by blocking the effects of histamine, a substance in the body that is primarily responsible for allergy symptoms [1, 2]
It is evident from the forced degradation study that both Pseudoephedrine hydrochloride (PSU) and FEX are fairly stable in acidic condition
It can be stipulated from this data that PSU and FEX are essentially stable in the stomach pH. Both drugs are fairly sensitive to basic medium which promotes their dissociation and consequent degradation reaction. These findings provide important information of selection of the pH of any dosage form containing PSU and/or
Summary
Fexofenadine hydrochloride (FEX) is a nonsedating antihistamine which works by blocking the effects of histamine, a substance in the body that is primarily responsible for allergy symptoms [1, 2]. As a rule of thumb pH of mobile phase should be at least 2 units above or below the pKa value of ionizable (acidic/basic) drug to ensure that only one form of analyte exists in solution [7, 8] From this point of view, pH selection in this method is a weak point as FEX possesses a pKa value of 4.28. In assay method the use of 16.3 g/L of n-octane sulphonic acid sodium salt (75 mM) seems to be astronomically high for the HPLC columns This high concentration of ion-pairing agent is detrimental to reversed phase column because ionpairing agents are not or completely washed out. The developed method was validated according to the ICH, USP, and FDA guideline
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
