RESUMO
The stability of adriamycin (ADR), adriamycinol, adriamycinone (ADR-ONE) and daunomycin in the presence of alpha-, beta- and gamma-cyclodextrins (CDs) was studied using high-performance liquid chromatography. It was found that alpha-CD did not affect the degradation of tested compounds, beta-CD caused a little effect and gamma-CD resulted in pronounced stabilizing effect. The formation of complexes between ADR and ADR-ONE with CDs was monitored by fluorescence spectroscopy. The fluorescence spectrum of ADR-gamma-CD complex had an activation maximum at 460 nm, emission maximum at 555 nm and a shoulder at 585 nm. A similar finding was observed in case of alpha-CD. In case of beta-CD, the fluorescence intensity at 580 nm peak enhanced less than in case of gamma-CD. With ADR-ONE, alpha-CD did not cause any significant change compared with the spectrum of free molecule. On the other hand, it was noticed that, the fluorescence spectra of ADR-ONE with both beta- and gamma-CD were the same but showed a significant difference to the spectrum of free molecule, especially the molar fluorescence of the 585 nm emission peak.
RESUMO
Adriamycin, adriamycinol, adriamycinone and duanorubicin were simultaneously determined by the development of an on-line plasma clean-up system. A short protein-coated Lichrosorb, RP-8, RP-2, CN and muBondapak phenyl as well as ODS silica have been examined for their performance as pre-columns. The drugs and metabolites were separated from weakly retained plasma components through two steps; phosphate buffer saline, pH 7.4 and 15% acetonitrile in 0.1 M sodium dihydrogen phosphate, pH 3. The chromatographic conditions were: ODS/TM column, flow rate 1 ml/min, 35% acctonitrile in 0.1 M sodium dihydrogen phosphate (pH 3) containing 0.3% heptafluorobutyric acid as mobile phase. The detection was carried out using fluorescence monitor operated at an emission 555 nm and excitation 460 nm. Good resolution was obtained within 13 min. This method is reproducible for analysis of drugs and metabolites (99.3-100.1%, CV < 2%) in plasma.
RESUMO
A novel high performance liquid chromatographic method (HPLC) is presented for the quantitative determination of piroxicam in capsule formulation (Feldene capsule). Samples are separated on a chemically bonded beta-cyclodextrin column (Cyclobond I) with a mobile phase of 75% 0.05M phosphate buffer (pH 7.0) and 25% methanol. The effluent is monitored by a spectrophotometric detector with a 254-nm filter. The method is rapid, accurate, and precise.
