A membrane microcontactor as a tool for integrated sample preparation

A membrane microcontactor suitable to perform liquid-liquid extraction as well as evaporation in order to conduct enrichment steps in sample preparation of organ samples has been designed, fabricated, and characterized. Spacers of 100- or 200-μm high were constructed in a metal substrate with a channel width of 13 mm and the extraction kinetics in these channels was evaluated. The spacers were designed such that at the entrance and exit region a uniform flow distribution could take place and that a uniform flow profile could be guaranteed along the channel, hence allowing a large freedom in sample volume to be processed. The extraction and evaporation kinetic behavior of the device was first evaluated by extraction of a drug candidate (4-(2,5-dimethyl-pyrrol-1-y1)-2-hydroxybenzoic acid). To evaluate the device under more challenging working conditions, a homogenized mice kidney sample containing the drug candidate that was administered in life condition was cleaned and enriched with the extraction and evaporation modules and characterized by high-performance liquid chromatography, yielding an overall analysis time of 15-20 min per sample only. The system has the potential to be operated in a continuous fashion, making it appealing to be implemented in screening or high-throughput applications.