A New Detection Method for the Biomarkers of Soybean Isoflavones in Human Urine on the Basis of Packed‐Fiber Solid‐Phase Extraction

Traditional dietary assessment methods such as 24‐h dietary recall methods are not accurate enough, and the biomarkers to objectively evaluate food consumption have become attractive recently. Soy isoflavones are a typical plant‐based estrogen that helps to slow menopause symptoms, helping to lower cholesterol levels and reduce the risk of arteriosclerosis, and studies have shown a significant correlation between urinary isoflavones excretion and soy intake, which can be used as a useful biomarker. Because of the complex urine sample matrix and the large range of isoflavone concentration, it is vital to develop a new detection method to decrease the impurities interference and increase the target concentration for accurate detection of urine isoflavones. In this study, a few types of nanofibers were prepared and utilized as solid‐phase extraction adsorbents for sample pretreatment, and the homemade packed‐nanofiber solid‐phase extraction columns were chosen to purify the matrix and concentrate the analytes. A new method for rapid detection of soybean isoflavones in urine on the basis of packed‐fiber solid‐phase extraction combined with ultraviolet spectrophotometer was established, which provides an efficient reference for assessment of individual dietary intake. Electrospun nanofibers were prepared and utilized as solid‐phase extraction adsorbents for sample pretreatment. Homemade packed‐nanofiber solid‐phase extraction columns were created to purify the urine matrix and concentrate the analytes; that is, packed‐fiber solid‐phase extraction (PFSPE). A new method for rapid detection of the biomarkers of soybean isoflavones in urine on the basis of PFSPE combined with ultraviolet spectrophotometry was established, which provides an efficient reference for assessment of individual dietary intake.