Sensitive determination of four camptothecins by solid-phase microextraction-HPLC based on a boronic acid contained polymer monolithic layer

Camptothecin (CPT) and its derivative have been revealed to possess special anti-cancer activity, extraction methods are necessary for trace determination of CPTs in complex samples. In this work, we prepared a high efficient boronic acid-based polymer monolithic layer for microextraction of CPTs. A disposable membrane filter-based extraction device was developed, and boronic acid groups were co-polymerized into a polyporous polymer skeleton and served as the monolithic sorbent. The prepared poly (4-VB-MA-TRIM) showed good stability and great extraction efficiency toward four CPTs. After optimization of extraction conditions, poly(4-VB-MA-TRIM)-based solid-phase microextraction was coupled HPLC for determination of CPTs in biological samples. The method exhibited low limits of detection of 0.05-0.2 ng mL(-1), which is significantly more sensitive than reported HPLC methods. The method also showed wide linear range (0.1-100 and 0.5-200 ng mL(-1)), good linearity (R-2 > 0.9981) and good reproducibility (RSD <= 3.76%). The method has been applied in plasma samples, with good selectivity and good recoveries ranging from 85.1 to 104.7%. (C) 2015 Elsevier B.V. All rights reserved.