Electrophoretic separations in ultrathin channels using microelectrode array detection

摘要

Capillar zone electrophoresis (CZE) has become a highly efficient separation technique especially suitable for the investigation of low-volume samples. This technique has been widely applied to provide high-resolution separations of species in biological microenvironments in and around single cells. CZE, however, is a serial technique in which a small plug of material is injection and then separated. In order to monitor constantly changing cellular microenvironments a technique is needed that combines the advantages of CZE with continuous injection. A method has been developed which employs a capillary to introduce sample into a thin rectangular channel for subsequent electrophoretic separation. Dynamic separations are achieved by moving the capillary across the width of the channel and detecting the eluting species via an integrated array of platinum electrodes. Neurotransmitter separations have been achieved with channels as thin as 0.6 mum using this method.