Shahram lotfi
Faculty of Sciences, Payame Noor University(PNU),Gilane Gharb , Iran

Abstract:

Tramadol is an analgesic drug with a similar chemical structure to codeine. Its analgesic effect is mediated through inhibition of noradrenaline re-uptake, both increased release and decreased re-uptake of serotonin in the spinal cord, and a weak effect on mu opioid receptors [1,2]. Several analytical methods for determination of tramado and its metabolites have been used such as gas chromatography [3], mass spectrometry [4] and fluorescence detection [5]. All these methods used are sophisticated and high cost in the laboratory studies. In this novel study, coupling the cloud point extraction strategy as a preconcentration method with the spectrophotometric monitoring device was used to detect the trace amount tramadol . The mixture of a nonionic surfactant (Triton X-114) and a cationic surfactant (CTAB) was utilized as a suitable micellar medium for preconcentration and extraction of tramadol. Tramadol was extracted with 0.3 (w/v) Triton X-114 and 0.5 ml of 1*10 -5 mol L−1 CTAB at pH= 9 The enriched mass was dissolved in the appropriate amount of DMF solvent and determined by the spectrophotometer at the wavelength 389 nm. Enrichment factor of was obtained for the preconcentration of target molecule. Under the optimal conditions, linearity was obeyed in the ranges of 55-570µgL−1 of tramadol concentration. The interference effect of a few interferes such as vitamins, amino acids, sugars, and metal ions on the extraction efficiency of tramadol were tested. Finally, the optimized conditions developed were successfully utilized for the determination of tramadol in the human blood and urine samples with satisfactory results.

References:

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[2] Stamer UM, Stuber F. Analgesic efficacy of tramadol if coadministered with ondansetron. Anesth Analg 2001;93:1626.

[3] Poulsen L, Arendt-Nielsen L, Brosen K, Sindrup SH. The hypoalgesic effect of tramadol in relation to CYP2D6. Clin Pharmacol Ther 1996;60:636-44.

[4] Ceccato A, Vanderbist F, Pabst J-Y, Streel B. Enantiomeric determination of tramadol and its main metabolite O-desmethyltramadol in human plasma by liquid chromatography-tandem mass spectrometry. J Chromatogr B 2000;748:65-76.

[5] Campanero MA, Calahorra B, Garcia-Quetglas E, Escolar M, Honorato J. High-performance liquid chromatographic assay for simultaneous determination of tramadol and its active metabolite in human plasma. Application to pharmacokinetic studies. Chromatographia 1998;48(7-8): 555-60.

Keyword: Mixed micellar medium, tramadol, Cloud point extraction.