title: Simultaneous determination of paracetamol and lornoxicam by RP-HPLC in bulk and tablet formulation.
abstract: OBJECTIVE
  The objective of the study was to develop simple RP-HPLC method for the simultaneous determination of paracetamol and lornoxicam without prior separation.
  
  
  METHODS
  In this method, Kromasil C8 (250 mm, 4.6 mm, 5 μm) column was used. The mobile phase used was methanol:phosphate buffer (60:40, v/v, pH 6.4), at flow rate of 1 ml min(-1). UV detection was monitored at 302 nm.
  
  
  RESULTS
  Calibration graphs were established in the range of 1-150 μg ml(-1) and 0.5-100 μg ml(-1) for paracetamol and lornoxicam, respectively. The average retention time for paracetamol and lornoxicam was found to be 3.15 ± 0.03 min and 5.25 ± 0.06 min, respectively. The detection limit and quantitation limit for paracetamol are 0.19 μg ml(-1) and 0.59 μg ml(-1) and for lornoxicam 0.10 μg ml(-1) and 0.31 μg mL(-1), respectively. The intraday and interday precision expressed as percent relative standard deviation were below 2%. The mean recovery of paracetamol and lornoxicam was found to be in the range of 99.03-101.2%.
  
  
  CONCLUSIONS
  The validated HPLC method was found to be rapid, precise and accurate and can be readily utilized for analysis of paracetamol and lornoxicam in bulk and in pharmaceutical formulations.
authors.affiliation: Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa, Kingdom of Saudi Arabia.
authors.forename: Mahesh
authors.initials: M
authors.lastname: Attimarad
keywords: HPLC; lornoxicam; paracetamol; simultaneous determination; validation