摘要
A microfluidic device equipped for in situ fluorescence detection and combined with an off-line microcolumn adsorption is proposed for the determination of lead in natural water. The precolumn adsorption is based on a microcapillary filled with aminopropyl silica. An efficient Pb2+ adsorption on aminopropyl silica was proved by Langmuir isotherm adsorption experiments. The maximum adsorption capacity was found to be 5.7 x 10(-4) mol g(-1). By using this solid phase extraction procedure (SPE), a 100-fold specific lead concentration was obtained. The concentrated solution was then run into a microfluidic device equipped for fluorescence detection and the complete procedure allows lead determination with a detection limit of 2 mu g L-1. Furthermore, it was found that these measurements are not disrupted by the addition of a large excess of other interfering cations.
- 出版日期2012-4