Determination of sparfloxacin and its photodegradation products by thin-layer chromatography with densitometry detection. Kinetic evaluation of the degradation process and identification of photoproduct by mass spectrometry

Abstract

A TLC-densitometric method was developed for the determination of sparfloxacin in the presence of its photodegradation products. Silica gel TLC F 254 plates were used as the stationary phase and methylene chloride : methanol : 2-propanol : ammonia 25% (4 : 4 : 5 : 2 v/v/v/v) as the mobile phase. The developed 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 1.00-3.00 mg per band, with the determination coefficient, R 2 , exceeding 0.9958. The method was shown to have good precision and intermediate precision, as reflected by the relative standard deviation values, lower than 2.72% and characterized by a recovery rate at three concentration levels from 93.60% to 103.90%. The limits of detection and quantification were respectively 0.16 and 0.48 mg per band. The photodegradation process of sparfloxacin followed the kinetics of a first order reaction for the substrate. Nine products of photodegradation were identified by UPLC-MS/MS. The structure of a product previously not identified was determined.

Determination of danofloxacin and its photodegradation products by HPLC-DAD. Kinetic evaluation of the degradation process and identification of photoproducts by mass spectrometry

“…Therefore there is a necessity to study the photodegradation and to develop new methods of separation and determination of uoroquinolones as well as their photoproducts in solutions that leads to numerous publications in this eld. [13][14][15][16][17] Analysis of DAN photodegradation in solutions was investigated in several papers. The existing research concerning the photostability of DAN in solutions was performed under different irradiation conditions (usually sunlight or uorescent light) and exposure time.…”

Photolysis of Antibiotics under Simulated Sunlight Irradiation: Identification of Photoproducts by High-Resolution Mass Spectrometry

“…16,37,33 One of them, PT 372, formed after fluorine solvolysis and hydroxylation of DAN, presented the highest intensity, followed by PT 356 and the defluorinated PT 340, previously described by Sturini and co-workers. 16 For sparfloxacin (SPAR), the occurrence of some of the photoproducts formed (m/z 389, 375, and 335) was already known 38,39 but their structural elucidation has not been achieved before. Additionally, up to 12 SPAR degradation products are reported here for the first time, with those with m/z 373 and m/z 335, related with defluorination and oxidation of the piperazine ring, respectively, being predominant (Figure S18).…”

Structural elucidation of gemifloxacin mesylate degradation product

“…The stability of the fluorquinolones class is much studied and there are many papers describing the isolation and identification of degradation products of these drugs. The main degradation factor of fluorquinolones is the UV radiation, showing mainly modifications in the piperazine and diazabicyclo rings of these molecules (Burhenne et al ., ; Lovdahl and Priebe, ; Hubicka et al ., ; Ahmad et al ., ), but the loss of the cyclopropyl group, hydroxylation of the substituent in position 7, dechlorination and defluorination are also described in the literature (Engler et al ., ; Fasani et al ., ; Lovdahl and Priebe, ; Hubicka et al ., ). The decarboxylation of lomefloxacin, moxifloxacin hydrochloride and sparfloxacin under acid conditions was described by Salem et al .…”