For specificity three solution (Working placebo, standard solution of moxifloxacin with 100µg/mL and 0.1N diluent) were prepared and two replicate of each concentration of the solution were injected. A working placebo solution is used to simulate the matrix in which the analyte is measured. The chromatogram of the working placebo solution showed no peak. This demonstrates that the method is not generating false positives from the placebo, indicating good specificity.