Abstract: A mutiplexed enzyme assay method and substrate set for performing the method are disclosed. The method includes performing a plurality of enzyme reactions in the presence of a plurality of enzymes substrates, under conditions effective to convert an enzyme substrate to a corresponding product, where the product of each substrate and the substrate have different separation characteristics from each other and from the other substrates and their corresponding products. After performing the reactions, which may be carried out in separate or combined reactions, the substrates and products in said reactions are separated in a single separation medium. For each separated product and substrate, a separation characteristic effective to identify that product and substrate and a signal related to the amount of the product and substrate is detected. From this, one can determine the amount of substrate converted to the corresponding product in each of the reactions.

Abstract: A mutiplexed enzyme assay method and substrate set for performing the method are disclosed. The method includes performing a plurality of enzyme reactions in the presence of a plurality of enzymes substrates, under conditions effective to convert an enzyme substrate to a corresponding product, where the product of each substrate and the substrate have different separation characteristics from each other and from the other substrates and their corresponding products. After performing the reactions, which may be carried out in separate or combined reactions, the substrates and products in said reactions are separated in a single separation medium. For each separated product and substrate, a separation characteristic effective to identify that product and substrate and a signal related to the amount of the product and substrate is detected. From this, one can determine the amount of substrate converted to the corresponding product in each of the reactions.

Abstract: A multiplexed enzyme assay method and substrate set for performing the method are disclosed. The method includes performing a plurality of enzyme reactions in the presence of a plurality of enzymes substrates, under conditions effective to convert an enzyme substrate to a corresponding product, where the product of each substrate and the substrate have different separation characteristics from each other and from the other substrates and their corresponding products. After performing the reactions, which may be carried out in separate or combined reactions, the substrates and products in said reactions are separated in a single separation medium. For each separated product and substrate, a separation characteristic effective to identify that product and substrate and a signal related to the amount of the product and substrate is detected. From this, one can determine the amount of substrate converted to the corresponding product in each of the reactions.

Abstract: A mutiplexed enzyme assay method and substrate set for performing the method are disclosed. The method includes performing a plurality of enzyme reactions in the presence of a plurality of enzymes substrates, under conditions effective to convert an enzyme substrate to a corresponding product, where the product of each substrate and the substrate have different separation characteristics from each other and from the other substrates and their corresponding products. After performing the reactions, which may be carried out in separate or combined reactions, the substrates and products in said reactions are separated in a single separation medium. For each separated product and substrate, a separation characteristic effective to identify that product and substrate and a signal related to the amount of the product and substrate is detected. From this, one can determine the amount of substrate converted to the corresponding product in each of the reactions.

Abstract: Methods, devices, and systems for unbiased transport of materials on a microfluidic device are disclosed, including methods of maintaining the starting composition of an analyte during transport, and methods of simultaneously analyzing both cationic and anionic components of an analyte. Analyte is loaded into a four-way junction of channels by controlled differential pressure applied to the channels. After analyte loading, an electrical potential is established, forcing charged species into at least one of two separation channels.

Abstract: A microscale fluid handling system that permits the efficient transfer of nanoliter to picoliter quantities of a fluid sample from the spatially concentrated environment of a microfabricated chip to "off-chip" analytical or collection devices for further off-chip sample manipulation and analysis is disclosed. The fluid handling system is fabricated in the form of one or more channels, in any suitable format, provided in a microchip body or substrate of silica, polymer or other suitable non-conductive material, or of stainless steel, noble metal, silicon or other suitable conductive or semi-conductive material. The microchip fluid handling system includes one or more exit ports integral with the end of one or more of the channels for consecutive or simultaneous off-chip analysis or collection of the sample. The exit port or ports may be configured, for example, as an electrospray interface for transfer of a fluid sample to a mass spectrometer.