Development and validation of liquid chromatography method for determination of acetylsalicylic and salicylic acid in dosage forms

Acetylsalicylic acid belongs to nonsteroidal anti-inflammatory drugs with antiinflammatory, analgesic and antipyretic properties. The aim of this work was development and validation of HPLC method for qualitative and quantitative analysis of acetylsalicylic acid and its major degradation product, salicylic acid, in dosage forms. The optimal separation was achived using Zorbax Eclipse XDB-C18 Analytical column (4,6x150 mm, particle size 5 μm) thermostated at 35°C. Mobile phase consisted of eluents A and B in ratio 65:35 (V/V). As the eluent A, water of HPLC purity and 85% phosphoric acid in ratio 80:0.5 (V/V) were used, while acetonitrile was used as the eluent B. The flow rate was 1.0 mL/min and UV detection was performed at 240 nm. The method was validated in terms of selectivity, linearity, precision, accuracy and robustness for both analytes, as well as limits of detection and quantification for salicylic acid. The obtained results meet the requirements of analytical procedures validation. The proposed HPLC method was applied in qualitative and quantitative analysis of acetylsalicylic and salicylic acids in six different forms of drugs. All obtained results meet the requirements of manufacturer specifications. The established HPLC method was found to be rapid, simple, accurate and selective for simultaneous determination of acetylsalicylic and salicylic acids in dosage forms.