Capillary detector cartridge for electrophoresis.

摘要

A capillary for electrophoresis is disposed in a cartridge body. The cartridge body is cooled and provides a serpentine path for the capillary. The capillary is disposed over the serpentine path and protrudes vertically downward from the bottom of the cartridge at two remote spaced apart locations at the bottom of the cartridge. These two remote spaced apart locations dispose the protruding capillary ends at the same elevation to restrict flow within the capillary to flow induced by electrical force or fluid pressure injection. These distal ends are sealed about their periphery with respect to the cartridge where they exit the cartridge. The distal ends protrude downwardly a sufficient distance from the bottom of the cartridge body to be able to become immersed in an electrolyte for filling the capillary (preferably at a high pressure on one end of the capillary -- about 10 psi), a sample for charging the capillary (at a low measure pressure at one end of the capillary -- about 1 psi) or an electrolyte at an electrical connection for causing electrophoresis in the capillary (with the same pressure at both ends of the capillary). One portion of the capillary adjacent to an end is registered to detector components defined by the cartridge. In one preferred embodiment the capillary is placed within a hollow cartridge body, spiral wound about a mandrel and cooled by a coolant, which can be forced circulated to dissipate by convection heat generated during the electrophoresis. An alternate construction includes a boron nitride block having a serpentine depression. A capillary is threaded to the required length in the serpentine depression, insulated at points of crossover to prevent undesired arcing, and pasted to the block with water soluble boron nitride paste. In both cases, the cartridge provides an immediately interchangeable site for electrophoresis which can conveniently be utilized for automatic electrolyte and sample injection, automated electrophoresis and automated detection without special filling connected to the capillary. Interchanging of the cartridge permits rapid change of length, detection mode and capillaries merely by the substitution of cartridges.