ORIGINAL_ARTICLE Two simple, sensitive, selective, precise, and accurate methods for determination of trimethoprim in different sulfonamide formulations intended for use in human and veterinary medicine were optimized and validated. The methods are based on the trimethoprim reaction with bromcresol green (BCG) and 2,4-dinitro-1-fluorobenzene (DNFB). As extraction solvents we used 10 % N,N-dimethylacetamide in methanol and acetone for both methods, respectively. The colored products are quantified applying visible spectrophotometry at their corresponding absorption maxima. The methods were validated for linearity, sensitivity, accuracy, and precision. We tested the method applicability on four different medicinal products in tablet and powder forms containing sulfametrole and sulfamethoxazole in combination with trimethoprim. The results revealed that both methods are equally accurate with recoveries within the range 95-105 %. The obtained between-day precision for both methods, when applied on four different medicinal products, was within in the range 1.08-3.20 %. By applying the F-statistical test (P<0.05), it was concluded that for three medicinal products tested both methods are applicable with statistically insignificant difference in precision. The optimized and validated BCG and DNFB methods could find application in routine quality control of trimethoprim in various formulation forms, at different concentration levels, and in combination with different sulfonamides. https://macvetrev.mk/Files/Article/2020/10.1515/macvetrev-2015-0069/macvetrev-2015-0069.pdf 2016-03-15T09:00:00 65 76 10.2478/macvetrev-2015-0069 medicinal products trimethoprim /Vis spectrophotometry validation Goran Stojković goranst@pmf.ukim.mk false 1 University “Ss. Cyril and Methodius”, Faculty of Natural Sciences and Mathematics, Institute of Chemistry, Skopje, Republic of Macedonia LEAD_AUTHOR Elizabeta Dimitrieska-Stojković false 2 University “Ss. Cyril and Methodius”, Faculty of Veterinary Medicine – Skopje, Institute for Food, Skopje, Republic of Macedonia AUTHOR Marija Soklevska false 3 University “Ss. Cyril and Methodius”, Faculty of Natural Sciences and Mathematics, Institute of Chemistry, Skopje, Republic of Macedonia AUTHOR Romel Velev false 4 University “Ss. Cyril and Methodius”, Faculty of Veterinary Medicine – Skopje, Institute for Food, Skopje, Republic of Macedonia AUTHOR Fresta, M., Furneri, P.M., Mezzasalma, E., Nicolosi, V.M., Pugeisi, G. (1996). Correlation of trimethoprim and brodimoprim physicochemical and lipid membrane interaction properties with their accumulation in human neutrophils, Antimicrob. Agents Chemother. 40(12): 2865 - 2873. PMid:9124856 PMCid:PMC163637 1 Saha, N., Kar, S.K., (1977). Metal complexes of pyrimidine-derived ligands - I: Nickel (II) complexes of 2-hydrazino-4,6-dimethyl pyrimidine, J. Inorg. Nucl. Chem. 39, 195-200. 2 10.1016/0022-1902(77)80465-X Shamsa, F., Amani, L. (2006). Determination of sulfamethoxazole and trimethoprim in pharmaceuticals by visible and UV spectrometry, Iran. J. Pharm. Res. 1, 31-36. 3 Reisberg, B., Herzog, J., Weinstein, L. (1967). In vitro antibacterial activity of trimethoprim alone and in combination with sulfonamides. Antimicrob. Agents Chemother., 424-426. 4 El-Ansary, A.L., Issa, Y.M., Selim, W. (1999). Spectrophotometric determination of trimethoprim in pure form and in pharmaceutical preparations using Bromthymol blue, Bromocresol green and Alizarin red S. Anal. Lett. 32(5): 655-969. 5 10.1080/00032719908542869 Gemperline, P.J., Cho, J. H., Baker, B., Batchelor, B., Walker, D.S. (1997). Determination of multicomponent dissolution profiles of pharmaceutical products by in situ fiber-optic UV measurements. Anal. Chim. Acta. 345, 155-159. 6 10.1016/S0003-2670(97)00095-0 Ni, Y., Q. Zj., Kokot, S. (2006). Simultaneous ultraviolet-spectrophotometric determination of sulfonamides by multivariate calibration approaches. Chemometr. Intell. Lab. 82, 241-247. 7 10.1016/j.chemolab.2005.07.006 Adekoge, O.A., Babalola, C.P., Kotila, O.A., Obuebhor, O. (2014). Simultaneous spectrophotometric determination of trimethoprim and sulphamethoxazole following charge-transfer complexation with chloranilic acid. Arabian Journal of Chemistry, in press 8 Othman S. (1989). Multicomponent derivative spectroscopic analysis of sulfamethoxazole and trimethoprim. Int. J. Pharm. 63, 173-176. 9 10.1016/0378-5173(90)90168-4 Zimmer, Ł., Czarnecki, W. (2010). Derivative spectrophotometric method for simultaneous determination of sulfadimidine and trimethoprim. Annales Universitatis Mariae Curie-Skłodowska, Lublin - Polonia, Sectio DDD, 23(1-3): 27-36. 10 Medina, J.R., Miranda, M., Hurtado, M., Dominguez-Ramirez, A. M., Ruiz-Segura, J.C. (2013). Simultaneous determination of trimethoprim and sulfamethoxazole in immediate-release oral dosage forms by first-order derivative spectroscopy: Application to dissolution studies. Int. J. Pharm. Pharm. Sci. 5 (Suppl.4), 505-510. 11 Rezaee, A., Nejad, Q.B., Kebriaeezadeh, A. (2000). Simultaneous analysis of thrimethoprim and sulphamethoxazole drug combinations in dosage forms by High Performance Liquid Chromatography. Iran. Biomed. J. 4 (2&3): 75-78. 12 Akay, C., Özkan, S.A. (2002). Simultaneous LC determination of thrimethoprim and sulfamethoxazole in pharmaceutical formulations. J. Pharm. Biomed. Anal. 30, 1207-1213. 13 10.1016/S0731-7085(02)00460-0 Lemus Gallego, J.M., Perez Arroyo, J. (2002). Simultaneous determination of dexamethazone and trimethoprim by liquid chromatography. J. Pharm. Biomed. Anal. 30, 1255-1261. 14 10.1016/S0731-7085(02)00468-5 Al-Sabha, T.N., Hamody, I.A. (2011). Spectrophotometric determination of trimethoprim using 2,4-dinitro-1-fluorobenzene reagent. J. Edu. & Sci. 24(2): 1-12. 15 Chati, S., Wadookar, S.G., Kasture, A.V. (1979). Nonaqueous titrimetric method for timethoprim determination in combination. Indian J. Pahrm. Sci. 41(6): 231. 16 Carapuca, H.M., Cabral, D.J., Rocha, L.S. (2005). Adsorptive stripping voltammetry of trimethoprim: mechanistic studies and application to the fast determination in pharmaceutical suspensions. J. Pharm. Biomed. Anal. 38(2): 364-369. PMid:15925233 17 10.1016/j.jpba.2005.01.005 Chatten, L.G., Stanley-Pons, B., McLeod, P. (1982). Electrochemical determination of trimethoprim. Analyst 107, 1026-103. PMid:7149266 18 10.1039/an9820701026 British Pharmacopoeia 2009, Volume I & II, p. 6201-6207. 19 ICH Harmonized tripartite guideline. Validation of analytical procedures: Text and methodology. Q2 (R1). (2005). International conference on harmonization of technical requirements for registration of pharmaceuticals for human use. 20 Miler, J.C., Miler, J.N. (1994). Statistics for analytical chemistry. 3rd Edition, Ellis Horwood Ltd. Chichester, West Sussex PMid:7819605 21 Profiles of drug substances, excipients and related methodology. In: Klaus Florey (Ed.), Analytical profiles of drug substances. Volume 7. (pp. 459). 1978, San Diego, California: Academic Press, USA. 22 Horwitz, W. (1982). Evaluation of analytical methods used for regulation of foods and drugs, Anal. Chem. 54 (1): 67A-76A. http://dx.doi.org/ 23 10.1021/ac00238a765 Ayad, M.R.R., Huda, M.A., Halah H. (2012). Spectrophotometric determination of trimethoprim in pure form and pharmaceutical formulations with metol and potassium hexacyanoferrate (III). Tikrit Journal of Pharmaceutical Sciences 8(2): 209-220. 24