Fluorescence and terbium-sensitised luminescence determination of garenoxacin in human urine and serum.

Fluorescence and terbium-sensitised luminescence properties of new quinolone garenoxacin have been studied. The fluorimetric method allows the determination of 0.060-0.600mugml(-1) of garenoxacin in aqueous solution containing HCl/KCl buffer (pH 1.5) with lambda(exc)=282nm and lambda(em)=421nm. Micellar-enhanced fluorescence was also studied, leading to a higher than 400% increase in analytical signal in presence of 12mM sodium dodecyl sulphate (SDS), allowing the determination of 0.020-0.750mugml(-1) of garenoxacin. The terbium-sensitised luminescence method allows the determination of 0.100-1.500mugml(-1) of garenoxacin in 12mM SDS solution containing 0.08M acetic acid/sodium acetate buffer (pH 4.1) and 7.5mM Na(2)SO(3) (chemical deoxygenation agent), with lambda(exc)=281nm and lambda(em)=546nm. Relative standard deviation (R.S.D.) values for the three methods were in the range 1.0-2.0%. The proposed procedures have been applied to the determination of garenoxacin in spiked human urine and serum.