A multi-channel bio-separation detection method and apparatus in which a single detector is coupled to a plurality of radiation sources, in a one detector/many radiation sources configuration. Each radiation source directs radiation at one detection zone of a single separation channel, and a single detector is applied to detect light emissions from the detection zones of several separation channels. The light sources direct radiation at the detection zones in a predetermined sequence and further in a cyclic manner, with the detector output synchronized to the light sources by a controller. Bio-separation may be conducted simultaneously in all the channels in parallel, with detection time-staggered and/or time multiplexed with respect to the light sources. In one embodiment, low cost light emitting diodes may be used as light sources. In another aspect, the detection scheme is configured for radiation induced fluorescence detection in a multi-channel capillary electrophoresis instrument.
A bio-separation system using an efficient, compact, portable, interchangeable, reusable, recyclable, multi-channel cartridge, has integrated pre-aligned optics and an integrated reagent reservoir. The cartridge supports, for example, multiple capillaries for CE separation. An integrated reservoir containing a separation support medium (e.g., a gel buffer) is common to all capillaries. The chemistry of the medium and the characteristics of the capillaries (e.g., capillary size, coating and length) are defined for each cartridge. Different cartridges can be easily interchanged in the bio-separation system to suit the particular sample based separation. The reservoir is coupled to an air pressure pump that pressurizes the gel reservoir to purge and fill the capillaries with buffer as the separation support medium. In another aspect of the present invention, optics requiring fine alignment with respect to the detection zones (such as fiber optics for directing incident radiation and/or radiation emissions) are integrated into the cartridge.
A bio-separation instrument using a multi-segment cartridge. The cartridge includes a plurality of efficient, compact, portable, interchangeable, reusable, recyclable, modular, multi-channel segments. Each segment supports multiple capillaries for CE separation. Each segment has an integrated reservoir containing a buffer/gel common to all the capillaries. Air pressure can be supplied to the reservoir through the periphery of each segment. Each segment has an integrated LED array board directly coupled to capillaries for providing excitation light. Optical fibers of a fiber bundle are individually guided through the periphery of each segment to the capillaries for emission collection. The fiber bundle delivers emissions to a detector that can read the emissions in a time-staggered multiplexed scheme. Each segment includes electrodes electrically coupled to a voltage source through the periphery of the segment for effecting CE separation. Providing each segment with pneumatic and voltage connections on the periphery and direct coupling LED's allow the segments to easily stack together for integration into the instrument.