Analytical methods for determination of isoflavones in complex matrices

Silva L. F., Sinisterra M. J., Lanças F. M.

Keywords: isoflavones, complex matrices, analytical methods, sample preparation, separation techniques.

Abstract: Isoflavones are an important subclass of phytoestrogens. They are throughout the plant kingdom, often present in our diet and are associated with several benefits to human health, such as prevention of cardiovascular diseases and breast cancer. These factors have aroused the interest of the scientific community, causing a significant increase in the number of publications related to these compounds in the last two decades. In this work we present an overview on sample preparation techniques, chromatographic separation techniques, and chromatography coupled to different detection techniques applied to the analysis of isoflavones in several matrices, from 2010 to the present days. Studies have reported on the analysis of isoflavones in soybean, soy derivatives, bovine milk, urine, plasma, water and others. Among the sample preparation techniques, there are reports involving LLE, SLE, SPE, QuEChERS, MSPD SPME and MEPS. Classical sample preparation techniques are often used. There are well-developed micro-techniques such as SPME and MEPS, however their use in sample preparation aiming to determine isoflavones is very limited, practically restricted to analytical development studies. Among the chromatographic techniques HPLC, UHPLC and GC are the most popular ones, being followed by the electrophoretic techniques. The most common detectors in this analytical niche are mass spectrometers and UV-Vis spectrophotometers, respectively.

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