Abstract: The invention is a device for counter-diffusion applications comprising a removable cartridge having a plurality of capillary tubes that may be disposed between first and second members. The first member may be moveable into at least a first and second position. The second member may be moveable into a sealing position wherein the distal ends of the capillary tubes contact a sealant material. In the first position, the proximal ends of the capillary tubes may contact a macromolecular solution, which may cause the macromolecular solution to diffuse into the interior space of the capillary tube. In the second position, the proximal ends of the capillary tubes may be inserted into a corresponding reservoir well having a precipitating solution. The macromolecular solution and the precipitating solution may then counter diffuse against each other in each capillary tube. The removable cartridge may then be removed and replaced with a new removable cartridge.

Abstract: A nucleic acid detector and a method of using the detector are disclosed for detecting the presence of target nucleic acid sequences within a sample. The nucleic acid detector comprises a substrate-bound, hairpin-shaped nucleic acid captor in conjunction with a labeled universal nucleic acid detector probe. The captor has a segment that is complementary to at least a portion of the target nucleic acid and is denatured and hybridized to the target under test conditions. Hybridization of the captor to the target maintains the captor in an open conformation which exposes an end portion of the captor to the universal detector probe. The detector probe is able to hybridize with the exposed end portion of the captor if the captor has hybridized with a target. The labeled detector probe is detectable by external detection methods. Detector probes having identical universal detector probe sequences may be used to identify the presence of multiple targets having various target sequences within a sample.

Abstract: The invention is a crystallization cassette and associated method for growing and analyzing macromolecular crystals in situ by X-ray crystallography. The cassette allows proteins (as well as other macromolecules) to be crystallized by the counter-diffusion method in a restricted geometry. Using this procedure, crystals can be adequately prepared for direct X-ray data analysis such that the protein's three-dimesional structure can be solved without crystal manipulation.

Abstract: A nucleic acid detector and a method of using the detector are disclosed for detecting the presence of target nucleic acid sequences within a sample. The nucleic acid detector comprises a substrate-bound, hairpin-shaped nucleic acid captor in conjunction with a labeled universal nucleic acid detector probe. The captor has a segment that is complementary to at least a portion of the target nucleic acid and is denatured and hybridized to the target under test conditions. Hybridization of the captor to the target maintains the captor in an open conformation which exposes an end portion of the captor to the universal detector probe. The detector probe is able to hybridize with the exposed end portion of the captor if the captor has hybridized with a target. The labeled detector probe is detectable by external detection methods. Detector probes having identical universal detector probe sequences may be used to identify the presence of multiple targets having various target sequences within a sample.