A simple and selective micellar electrokinetic chromatography (MEKC) with UV detection is described for simultaneous determination of amikacin, tobramycin, and kana mycin A, performed in Tris buffer (180 mm; pH 9.1) with 300 mm sodium pentanesulfo3 nate (SPS) as an anionic surfactant. Under this condition, good separation with high efficiency and the required short analysis time is achieved. The linear ranges of the method for the determination of amikacin, tobramycin, and kanamycin A were 0.1 0.5 mg/mL, 0.4-2.0 mg/mL, and 0.4-2.0 mg/mL, respectively; the detection limits (signal-to-noise ratio = 3; injection, 0.5 psi 5 s) were 0.08, 0.2, and 0.2 mg/mL, respectively. The small amount of sample required and the expeditiousness of the procedure allow content uniformity to be determined in individual commercial products.