Determination of certain preservatives by hplc after ultrasound assisted cloud point microextraction in real samples

Ultrasound-assisted cloud point microextraction (UA-CPME) was performed for certain preservatives (p-hydroxy benzoic acid and its alkyl esters, methyl, ethyl, propyl and butyl paraben). Then, an HPLC method was developed for their simultaneous determination in pharmaceutical and cosmetic samples. The chromatograms of these substances were recorded on a C18 column using gradient elution technique with various solvent systems at different flow rates and at 254 nm wavelength using Diode-Array Detector (DAD). Analysis of Variance (ANOVA) test was applied to ensure result reliability. ANOVA test was used to determine the reliability of the results. A model was created with the obtained data. The developed method was validated by examining linearity, reproducibility, accuracy, limit of quantification and limit of the detection. Methyl paraben with 0.148% of RSD% value and 0.060% relative error%, and propyl paraben with 0.149% of % RSD value and 0.120% of relative error% were determined in the syrup sample by the developed method. Methyl paraben with recovery values of (98.32-99.42) % and ethyl paraben with recovery values of (99.17-99.41) %, were determined in hand cream.