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VOL. 72 (4), 599-609, 2006 VANADIUM IN VIVO INTERACTION WITH CEFATOXINE

The mobile phase reagents used were HPLC grade methanol from
Scharlau. Water used was from a Milli-Rho-Milli-Q system (Millipore,
Bedford, MA, USA). Phosphate buffer (0.1 M) was prepared with
phosphate monopotasic anhydride and o-phosphoric acid supplied
by Merck.

Apparatus and instrument

Kontron high-pressure liquid chromatograph equipped with a
Kontron 420 pump. An automatic injector with 6 valves Kontron
Auto Sampler 460. A variable-wavelength UV detector of Kontron
Uvikon 735 LC. Phenomenex C18 column (25 x 0.46 cm), fulled with
particles of 5 µm, besides this column of separation, a precolumn
and a protective column fulled with the same material that the first
column were used. A Kontron Station Data with D450 software was
used to control the detector and injector, on the other hand it allowed
the integration of the chromatogram peaks and it cuantificated the
results.

ANALYTICAL PROCEDURE

The extraction of cefotaxime in blood was carried out by means
of protein precipitants such as trichloroacetic acid (8) in the
concentration 10%. 1.5 mL of this reagent was added to 0.5 mL of
blood. This mixture was centrifuged at 3000 rpm for 5 min. The
supernatant was collected through a Pasteur pipet and filtered
through MFS disks of nylon of 0.4 mm of diameter. After that, it was
assayed by HPLC.

The extraction of cefotaxime in organs such as liver, spleen,
kidney, lung and heart, was carried out by means of trichloroacetic
acid 20%. 2 mL of this reagent were added to 0.5 g of dry weight
of each organ. Each mixture was done homogeneous and was
centrifuged at 3000 rpm for 10 min. The supernatant was collected
through a Pasteur pipet and filtered through MFS disks of nylon of
0.4 mm of diameter. It was later assayed by HPLC.

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