uv spectrophotometric profile of doxycycline hyclate

UV SPECTROPHOTOMETRIC PROFILE OF DOXYCYCLINE HYCLATE
Kogawa, A C*; Nunes Salgado, HR
[email protected], [email protected]
Universidade Estadual Paulista “Júlio de Mesquita Filho” UNESP Campus de Araraquara Departamento de
Fármacos e Medicamentos
Rodovia Araraquara - Jaú Km1 Bairro dos Machados CEP 14800-901 Araraquara, São Paulo, Brazil
INTRODUCTION
A simple, sensitive and accurate spectrophotometric method was developed for the assay of doxycycline
hyclate in raw material and tablets. The validation method yielded good results and included the range,
linearity, precision and accuracy. The absorbance was measured at 273 nm for doxycycline hiclate solutions.
This drug is a broad-spectrum antibiotic derived from oxytetracycline, used in Brazil and the rest of the world
as both human and veterinary medicine, as well as in animal nutrition. Its method of analysis is not in the
Brazilian Pharmacopoeia. On the other hand, it is described in the British Pharmacopoeia an UV
spectrophotometry analysis, to which is recommended the preparation of solutions using a mixture of
hydrochloric acid and methanol as solvent. The aim of this work was to investigate the use of water solutions
in the UV spectrophotometric method of doxycycline hyclate, since it is soluble in this solvent.
MATERIALS AND METHODS
Spectrophotometer UV Shimadzu, quartz cells, aqueous solutions of doxycycline hyclate in concentrations
100 mg/ml (1); 50 mg/ml (2); 25 mg/ml (3); 12.5 mg/ml (4); 6.25 mg/ml (5) and 3.125 mg/ml (6). A standard
calibration curve of doxycycline was constructed by plotting absorbance versus concentration The dilutions
were analyzed individually in the UV and using their respective absorbance values an absorption curve was
constructed.
RESULTS
In the spectrophotometer, peaks were obtained in two wavelengths: 273 and 345nm. When we fixed the
wavelength at 273nm, we obtained the following absorbance values: 3.0277 (1); 1.5333 (2); 0.7834 (3);
0.4094 (4); 0.2272 (5) and 0.1272 (6). By setting the wavelength at 345 nm, we had the following absorbance
values: 2.5630 (1); 1.2792 (2); 0.6464 (3); 0.3323 (4); 0.1790 (5) and 0.0984 (6). The construction of the
concentration by absorbance graph showed correlations of 0.9999 and 0.9999, respectively. The precision
and accuracy of the assay, as well as the linearity of the calibration curve were determined for intra- and interday on three different days. The precision was expressed as the percent coefficient of variation of each curve.
The statistical data were calculated by ANOVA.
CONCLUSIONS
The doxycycline hyclate showed a linear relation between absorbance and concentration in both wavelengths.
Doxycyline was shown to be stable during all the procedure. Thus, the results parameters demonstrated that
the spectrophotometric method could be applied for the analysis of the pharmaceutical formulations assuring
the quality and efficacy of the doxycycline hyclate under investigation. It was also found that the excipients in
the commercial product did not interfere with the method.
REFERENCES
BRASIL. Resolução 899 de 2003. Guia para validação de métodos analíticos.
BRITISH PHARMACOPOEIA (BP). Her Majesty’s Stationary Office, London, v. I, 2010.FARMACOPÉIA
BRASILEIRA. 4. ed. São Paulo, Atheneu, 1988.
IFPMA. IFPA issue paper. Quality assurance of medicines. Suiça: International Federation of Pharmaceutical
Manufacturers Associations. 1997.
INSTITUTO NACIONAL DE METROLOGIA, NORMALIZAÇÃO E QUALIDADE INDUSTRIAL
(INMETRO). Orientação sobre validação de métodos de ensaios químicos, DOQ-CGCRE-008, 2007.
INTERNATIONAL CONFERENCE ON HARMONIZATION (ICH). Validation of Analytical Procedures:
Text and Methodology Q2(R1), Geneva, 2005.