Study of temperature factor in gradient and isocratic HPLC separation

5 Abstract This thesis was focused on the determination of the temparature influence upon analysis of phenolic acids and fluoroquinolone antibiotics using high performance liquid chromatography. Analysis was performed on Zorbax SB C18 (50 x 4.6 mm; 1.8 µm) analytical column using ultra - viollet detection (UV) for both phenolic acids and fluoroquinolon antibiotics. The optimization of separation conditions was carried out for determination of phenolic acids and fluoroquinolone antibiotics. The effect of composition and concentration of aqueous part of mobile phase and especially the effect of temperature was investigated. The gradient elution was used for determination of phenolic acids. The mobile phase was formed by 0.1% formic acid and methanol. The isocratic elution was used for determination of fluoroquinolone antibiotics and the mobile phase was also formed by 0.1% formic acid and methanol. Accelerating of analysis and saving time and used solvents by using higher temperature were the main goals of this thesis. This premise came true in the analysis of phenolic acids. The analysis was faster with good peak resolution. The results for fluoroquinolone antibiotics were not better than basic 25žC measurement. Contrariwise, lower than laboratory temperature was more advantageous for their analysis. System..