Determination of Danofloxacin and Its Photodegradation Products by Thin-Layer Chromatography: Kinetic Evaluation of Degradation Process

Abstract

& TLC-densitometric method was developed for determination of danofloxacin (DAN) in presence of its photodegradation products. Silica gel HPTLC Lichrospher 60 F 254 plates were used as the stationary phase and methanol:acetone:1 M citric acid:triethylamine (2.8:2:0.2:0.5, v=v=v=v) as the mobile phase. The elaborated method meets the acceptance criteria for specificity, linearity, sensitivity, accuracy, and precision. The linear regression analysis for the calibration curve showed a good linear correlation over the concentration range 1.25-3.75 lg per band, with determination coefficient, exceeding 0.9806. Accuracy of the method expressed as % recovery at three concentration levels was from 95.56% to 97.30%. Good precision and intermediate precision with % RSD less than 0.92% was also observed. The limits of detection and quantification were respectively 1.10 and 3.40 ng per band. Satisfactory results of validation of the method were also confirmed by determination of DAN in veterinary commercial preparation. The photodegradation process of DAN followed kinetics of the first order reaction for the substrate.

Investigation of olopatadine hydrochloride under stress conditions by hydrophilic interaction liquid chromatography

“…Za opisivanje reakcija koristi se zakon brzine reakcije, koji može imati diferencijalni i integralni oblik što je opisano u literaturi [14,30], a način određivanja reda reakcije dat je u radovima [31,32]. Kao konačan podatak izračunava se konstanta brzine reakcije [33][34][35].…”

Chromatographic-Densitometric Analysis of Chosen Fluoroquinolones on TLC Plates Using Mobile Phases with Different Viscosity

“…TLC has also been used for determination of fluoroquinolones in the presence of photodegradation products [17][18][19] . TLC coupled with electrospray ionization mass spectrometry was highlighted for screening of teteracycline and fluoroquinolone antibiotics in milk [20] .…”

“…By the use of this mobile phase eight of examined antibiotics (CIP, DAN, DIF, ENR, MAR, NOR, OFL and ORB) were separated (Figure 6). The R F values of the separated compounds are different and are in the range from 0 19. …”