Bioanalytical Systems, Inc.

Curtis E Bohs

Candice B Kissinger

Donnie A Evans

James M Hampsch

Scott R Peters

W Gamini Gunaratna

Michael C Linhares

William F Schmidt

William J Schmidt

Peter T Kissinger

A movement-responsive system for conducting tests on freely-moving animals is disclosed. The invention includes a container for housing the animal, a mechanism for rotating the container in response to rotational movement of the animal, and one or more test leads connected to the animal for performance of biomedical tests such as infusion, in vivo ultrafiltration, laser-doppler monitoring of blood flow, electrical stimulation and in vivo microdialysis, and a method for automated micro sampling of body fluids in free-moving animals. Because the cage is rotated in response to the animal's rotational movement, no swivel connectors are needed. A rotational sensor assembly is provided to detect rotational movement of the animal within the container. A vertical sensor assembly is mounted to the counterbalanced arm for monitoring vertical movements of the animal. The outputs of the sensor assemblies are routed to a computer or other device for monitoring and/or analyzing the activity of the animal. The container is configured to act as an operant chamber or a metabolic chamber by locating a hole in the bottom of the container and through the rotating mechanism. The invention also enables a new method for sampling body fluids of the animal without restricting the animal's movements. The sampling method uses a syringe pump to result in high fidelity fluid control greatly increasing repeatability of experiments. Further, the method employs pinch valves to control fluid flow in conjunction with an anticoagulant coated tubing, thereby resulting in a blood sampling method that does not require the use of heparinized sterile saline solution as a wash fluid.

Movement-response system for conducting tests on freely-moving animals

A movement-responsive system for conducting tests on freely-moving animals is disclosed. The invention includes a container for housing the animal, a mechanism for rotating the cage in response to rotational movement of the animal, and one or more test leads connected to the animal for performance of biomedical tests such as infusion, in vivo ultrafiltration, laser-doppler monitoring of blood flow, electrical stimulation, and in vivo microdialysis. The container is caused to rotate in the opposite (counter-rotation) direction of the sensed direction of rotation of the animal so that the one or more test leads do not become entangled, twisted, disconnected, or clamped. The rotating mechanism includes a simple, reliable sensor assembly including a pair of strategically placed, close-ended limit detectors which are activated by a triggering element, which is also a part of the sensor assembly. The sensor assembly is mounted on a counter-balanced arm which is responsive to upward and downward movements of the animal. No complex control system is required for the present invention, yet adjustment of the sensitivity of the rotating mechanism is easy to accomplish and may be performed by the average user of the apparatus. Further, the leads may all be continuous, thereby eliminating problems caused by the use of liquid swivels with independently rotating halves, or by commutator connectors.

Movement--responsive system for conducting tests on freely-moving animals

An electrochemical detector cell includes a first block having a planar first working surface, and a first working electrode embedded in the first block member. The first working electrode includes analyte contacting surface disposed co-planarly with the first working surface. A second block member has the second working surface placeable in an opposed, adjacent relation to the first working surface, and has an inlet port disposed an opposed, adjacent relation to the analyte contacting surface of the first working electrode. The second block also includes a coupling means for permitting an analyte delivery tube to be coupled to the second block member to position an end of the analyte delivery tube adjacent to the inlet port. A generally circular circumferential channel for collecting analyte is disposed radially outwardly of the first working electrode. An outlet is disposed at the channel for conducting analyte away from the channel. A reference electrode is disposed in a diametrically opposed relation to the outlet, and a ring-like gasket is placeable between the first and second block members for maintaining the first and second working surfaces in a predetermined spaced relation. The gasket includes a radially inner diameter disposed radially outwardly of the channel. The inlet port, channel, first working electrode, first working surface, second working surface, gasket and outlet port are configured to create a generally centrosymmetric thin layer radial flow path for the analyte across the working electrode, and between the first and second working surfaces, into the channel and out of the outlet port.

Electrochemical detector cell

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West Lafayette, IN, United States of America

Curtis E Bohs