QuEChERS: A new sample preparation approach for the determination of ibuprofen and its metabolites in soils

• DOI: 10.1016/j.scitotenv.2012.06.035
• Publication Date: 2012-07-15T18:33:38Z
• Authors: Idalina Bragança; Alexandra Plácido; Paula Paíga; Valentina F. Domi...; Cristina Delerue-...
• Keywords: QuEChERS; Sample Preparation; Hydrochloric acid; Matrix (chemical analysis); Soil test

Ibuprofen is one of the most used active pharmaceutical ingredients worldwide. A new method for the analysis of ibuprofen and its metabolites, hydroxyibuprofen and carboxyibuprofen, in soils is presented. The extraction of these compounds from the soil matrices was performed by using a modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) method. The method involves a single extraction of the investigated compounds with purified water (acidified at pH 2.5 with hydrochloric acid), and a slow and continuous addition of the QuEChERS content, followed by the addition of acidified acetonitrile (1% acetic acid), prior to the determination by liquid chromatography coupled with fluorescence detection (LC-FLD). Validation studies were carried out using soil samples with a range of organic carbon contents. Recoveries of the fortified samples ranged from 79.5% to 101%. Relative standard deviations for all matrix-compound combinations did not exceed 3%. The method quantification limits were ≤22.4 μg kg(-1) in all cases. The developed method was applied to the analysis of sixteen real samples.