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Development of a rapid and reproducible TLC method for purity elucidation and related substance identification of metronidazole in metronidazole dosage forms

Sylvia Atanasova-Stamova, Svetlana Georgieva, Maya Georgieva


Introduction: Thin-layer chromatography (TLC) is a quick, inexpensive microscale technique applicable for determination of the number of components in a mixture, monitoring the progress of an organic reaction, verification of substance identity and analysis of the fraction obtained from column chromatography.

Aim: The aim of our work is to develop a rapid TLC method for related substance identification, purity elucidation, and control of synthesis of metronidazole in dosage forms and during synthesis of derivatives.

Materials and Methods: A rapid and reproducible TLC method for quality determination of metronidazole derivatives is described. The samples and standard were separated on silica gel 60 with fluorescent indicator UV254 plates with three different mobile phases: A) acetic acid-ammonia-acetone-methylene chloride cyclohexane (1:2:3:3:1), B) toluene-chloroform-methanol (2:7:1), C) toluene-chloroform-ethanol-acetic acid-ammonia (9:8:1:1:1). The visualization of spots was done at 254 nm.

Results: As most appropriate was established to be the mobile phase consisting of toluene- chloroform-ethanol-acetic acid-ammonia (9:8:1:1:1). The identification and determination of metronidazole in analyzed drug formulations were proved by the correspondence between the Rf of drug samples and reference standard Rf-0.58.

Conclusion: The TLC method for related substance determination of metronidazole in drug formulations is an informative, rapid, and reproducible method. The method may be applied for further analysis and monitoring of synthesis of new metronidazole derivatives.



TLC method, purity elucidation, metronidazole, tablet dosage forms

Full Text


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About The Authors

Sylvia Atanasova-Stamova
Medical University of Varna, Department of Pharmaceutical Chemistry, Faculty of Pharmacy

Svetlana Georgieva
Medical University of Varna, Department of Pharmaceutical Chemistry, Faculty of Pharmacy

Maya Georgieva
Medical University of Sofia, Department of Pharmaceutical Chemistry, Faculty of Pharmacy

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