Quinone-based fluorophores and enhanced native fluorescence techniques were applied for a fast quantitative analysis of gemifloxacin mesylate (GEM) and linezolid (LIN) in pharmaceutical formulations. For this purpose, three sensitive, accurate and precise spectrofluorimetric methods were developed. GEM, as an n-electron donor, reacts with 7,7,8,8-tetracyanoquinodimethane (method A) and 2,5-dichloro-3,6-dihydroxy-p-benzoquinone (method B) as п-electron acceptors, forming charge transfer complexes that exhibit high fluorescence intensity at 441 and 390 nm upon excitation at 260 and 339 nm, respectively. Method C depends on measurement of enhanced native fluorescence of LIN in phosphate buffer (pH 5) at 380 nm upon excitation at 260 nm. Experimental factors affecting fluorescence intensity were optimized. Linearity was obtained over concentration ranges 50-500, 10-60 and 20-400 ng mL-1 for methods A, B and C, respectively. The developed methods were validated and successfully applied for determination of the cited drugs in tablets.
1. T. L. Lemke, D. A. Williams, V. F. Roche and S. W. Zito, Foye’s Principles of Medicinal Chemistry, 6th ed., Wolters Kluwer, Lippincott Williams & Wilkins, New York 2008.
2. M. J. O’Neil, P. E. Heckelman, C. B. Koch, K. J. Roman, C. M. Kenny and M. R. D’Arecca, The Merck Index, An Encyclopedia of Chemicals, Drugs and Biologicals, 14th ed., Merck Research Laboratories Division of Merck & Co., Inc., Whitehouse Station (NJ) 2006.
3. B. A. Moussa, M. A. Mahrouse, M. A. Hassan and M. G. Fawzy, Stability indicating spectrophotometric and TLC densitometric methods for the determination of gemifloxacin mesylate in tablet form, Anal. Chem. Indian J. 12 (2013) 165-176.
4. C. S. Paim, F. Fuhr, M. Steppe, E. Schapoval and S. Eva, Gemifloxacin mesylate: UV spectrophotometric method for quantitative determination using experimental design for robustness, Quimica Nova. 35 (2012) 193-197; DOI: 10.1590/S0100-40422012000100033.
5. R. El-Bagary, N. F. Abo-Talib and M. B. N. Eldin, Validated stability indicating assay of gemifloxacin by different chromatographic and spectrophotometric methods of analysis, J. Chem. Pharm. Res. 3 (2011) 562-570.
6. S. S. Panda, B. V. V. Ravi Kumar, K. S. Rao, V. R. Kumar and D. Patanaik, Difference spectrophotometric determination of gemifloxacin mesylate in tablet formulation, Asian J. Biochem. Pharm. Res. 1 (2011) 442-447; DOI: 10.1002/bio.2347.
7. K. B. C. Sekhar, D. Madhuri and N. Devanna, Direct and derivative spectrophotometric determination of gemifloxacin mesylate via metal chelate, Acta Cienc. Indica, Ser. Chem. 36 (2010) 165-171.
8. R. Rote Ambadas and S. P. Pingle, Validated UV-spectrophotometric methods for determination of gemifloxacin mesylate in pharmaceutical tablet dosage forms, E-J. Chem. 7 (Suppl. 1) (2010) S344-S348; DOI: 10.1155/2010/346847.
9. D. Madhuri, K. B. Chandrasekhar, N. Devanna and G. Somasekhar, Direct and derivative spectrophotometric determination of gemifloxacin mesylate in pure form and pharmaceutical preparations using p acceptors, Int. J. Pharm. Sci. Res. 1 (2010) 222-230.
10. Z. Y. Al Shoaibi and A. A. Gouda, Spectrophotometric methods for the determination of gemifloxacin mesylate in pure form and pharmaceutical formulations, Anal. Chem: Indian J. 9 (2010) 129-136.
11. M. V. Krishna and D. G. Sankar, Utility of s and p-acceptors for the spectrophotometric determination of gemifloxacin mesylate in pharmaceutical formulations, E-J. Chem. 5 (2008) 493-498; DOI: 10.1155/2008/801545.
12. S. E. K. Tekkeli and A. Önal, Spectrofluorimetric methods for the determination of gemifloxacin in tablets and spiked plasma samples, J. Fluoresc. 21 (2011) 1001-1007; DOI: 10.1007/s10895-010-0759-1.
13. N. F. Youssef and L. I. Bebawy, Spectrofluorometric methods for the determination of gemifloxacin mesylate and cefamandole nafate in bulk powder and pharmaceutical preparations, Bull. Fac. Pharm. Cairo Univ. 44 (2006) 215-227.
14. A. A. Elbashir, B. A. Saad, S. M. Abdussalam, K. M. M. Al-Azzam and H. Y. Aboul-Enein, Validated stability indicating assay of gemifloxacin and lomefloxacin in tablet formulations by capillary electrophoresis, J. Liq. Chromatogr. Rel. Tech. 31 (2008) 1465-1477; DOI: 10.1080/10826070802039481.
15. A. R. Rote and S. P. Pingle, Reversed phase-HPLC and HPTLC methods for determination of gemifloxacin mesylate in human plasma, J. Chromatogr. B 877 (2009) 3719-3723; DOI: 10.1016/ j.jchromb.2009.08.013.
16. D. Nagavalli, G. Abirami and S. K. Kumar, Validated HPLC method for the simultaneous estimation of gemifloxacin mesylate and ambroxol hydrochloride in bulk and tablet dosage form, J. Pharm. Res. 4 (2011) 1701-1703.
17. J. H. Block and J. M. Beals, Wilson and Grisvold's Textbook of Organic Medicinal and Pharmaeutical Chemistry, 11th ed., Wolters Kluwer, Lippincott Williams & Wilkins, New York 2004.
18. M. M. Annapurna, K. S. Kumar and M. V. V. S. G. Reddy, New derivative spectrophotometric methods for the determination of linezolid - an antibacterial drug, J. Chem. Pharm. Res. 4 (2012) 714-718.
19. S. A. Patel, P. U. Patel, N. J. Patel, M. M. Patel and U. V. Bangoriya, High performance thin layer chromatographic method for estimation of linezolid in tablets, Indian J. Pharm. Sci. 69 (2007) 571-574; DOI: 10.4103/0250-474X.36948.
20. S. Mohapatra, M. M. Annapurna, B. V. V. Ravi Kumar, M. Anwar, M. H. Warsi and S. Akhter, Validated stability indicating RP-HPLC method for the estimation of linezolid in a pharmaceutical dosage form, J. Liq. Chromatogr. Rel. Tech. 34 (2011) 2185-2195; DOI: 10.1080/10826076. 2011.585548.
21. L. Vlase, D. Muntean, M. Cuciureanu, R. Cuciureanu and S. Gocan, High-throughput determination of linezolid in human plasma by liquid chromatography tandem mass spectrometry, J. Liq. Chromatogr. Rel. Tech. 34 (2011) 436-445; DOI: 10.1080/10826076.2011.555677.
22. D. Cattaneo, S. Baldelli, F. Conti, V. Cozzi and E. Clementi, Determination of linezolid in human plasma by high-performance liquid chromatography with ultraviolet detection, Ther. Drug Monit. 32 (2010) 520-524; DOI: 10.1097/FTD.0b013 e3181d5eeee.
23. N. M. El-Enany, A. Abdelal and F. Belal, Spectrofluorimetric determination of sertraline in dosage forms and human plasma through derivatization with 9-fluorenylmethyl chloroformate, Chem. Central J. 5 (2011) 56-63; DOI: 10.1186/1752-153X-5-56.
24. International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use, Q2 (R1): Validation of Analytical Procedures: Text and Methodology, ICH, Geneva 2005.
25. D. Liming, X. Qingqin and Y. Jianmei, Fluorescence spectroscopy determination of fluoroquinolones by charge-transfer reaction, J. Pharm. Biomed. Anal. 33 (2003) 693-698; DOI: 10.1016/50731-7085(03)00365-0.
26. M. F. Abdel Ghany, A. M. El Kosasy, M. F. Ayad and L. E. Abdel Fattah, Spectrophotometric and spectrofluorimetric determination of gentamicin and tobramycin using 1,4-benzoquinone, Bull. Fac. Pharm. Cairo Univ. 41 (2003) 69-88.
27. S. Sharif, I. U. Khan, T. A. Sheikh, Y. Sharif and M. Ashfaq, Validated stability-indicating HPLC method for analysis of gemifloxacin in tablet formulations, Acta Chromatogr. 41 (2011) 95-107; DOI: 10.1556/AChrom.23.2011.1.6.
28. J. Li and H. Wu, HPLC determination of linezolid plasma concentration, Chin. J. Mod. Appl. Pharm. 27 (2010) 353-355.