2.7.2. Linearity
Calibration standards were prepared from the ciprofloxacinstock solution at 7 concentration levels ranging from 0.05 to8 g/ml. This incorporates the clinically relevant plasma concentra-tion range [15,16]. Peak area ratios (ciprofloxacin/IS) were plottedagainst the corresponding ciprofloxacin concentrations in plasma.Least-squares linear regression analysis of the calibration data wasperformed using the linear equation y = mx + c.