A Green RPLC Approach to Some Tetracyclines Analysis in Human Urine

In the study conducted, an environmentally friendly RPLC method using non-toxic ethanol instead of toxic organic solvents such as acetonitrile and methanol organic solvents was developed for the determination of 4-epitetracycline, 4-epioxytetracycline, and tetracycline, which are compounds of the tetracycline group with a broad spectrum of activity, in spiked human urine. In developing the liquid chromatographic method for the compounds studied, their liquid chromatographic behavior in the pH range of 2.5-7.0 was systematically investigated and the condition with 10% (v/v) ethanol in its structure, pH 3.0, and a column temperature of 37 oC was determined to be the optimum condition. Validation and robustness tests of the developed method were then carried out by the ICH guidelines. As a result of the validation and robustness tests, it was determined that the developed method is suitable for use in routine analyses. The developed method is linear in the range of 0.5-3.0 µg.mL-1 and the recovery results of the investigated compounds from spiked human urine were close to 100%. In addition, the greenness of the method developed in this study was evaluated using the Analytical Greenness Metric Approach (AGREE) and Green Analytical Procedures Index (GAPI) programs.