Simple, selective and accurate differential first derivative spectrophotometric method (ΔD1) was developed for the determination of florfenicol in bulk and pharmaceutical formulation. The developed method was based on measuring the ΔD1 of florfenicol in alkaline solutions against its aqueous solutions as blank. Beer's law was found to be linear over the concentration range 3-15 μg/mL with good correlation coefficient (0.999). The selectivity of the method was proved through freedom from interferences
Differential, First derivative, Florfenicol, Alkaline solutions