A portable stir-disc solid phase extraction using biochar/sodium alginate mixed matrix membrane as absorbent for...

Recently, we designed a novel portable stir-disc SPE device. Biochar/sodium alginate (SA) mixed matrix membrane (MMM) was introduced as stir-disc SPE adsorbents for the first time. The stir-disc SPE device efficiently and conveniently extracted bisphenol contaminants in water samples. The biochar/SA MMM exhibited satisfactory adsorption properties and excellent reusability. The established pretreatment method was then successfully applied to extract five traces of BPs in water samples. The targets were sensitively detected by a high-performance liquid chromatography/fluorescence detector (HPLC-FLD). The factors including exaction time, elution time, type and volume of elution solvent, and sample solution pH were thoroughly optimized. The methodology validation indicated that the limits of detection for the BPs ranged from 0.06 to 0.17 ng·mL^-1. The correlation coefficient (R²) of linearity was 0.9959-0.9994. Satisfactorily, the recoveries of five BPs ranged from 71% to 108%, and the RSD was less than 13.3%. The proposed method was effectively applied to analyze BPs in tap water, drinking water, and river water samples. The results of recycling experiments revealed that the biochar/SA MMM had excellent reusability for analyzing BPs in water samples. Therefore, this study offered a new perspective on sample treatment.