Abstract: Coagulation is detected in a fluid sample such as blood which has been inserted into a cartridge and operated on by an actuator mechanism. The cartridge may be of either of two types: a plunger sensor cartridge wherein a plunger assembly is reciprocated in a predetermined manner within the fluid sample and the descent of the plunger assembly is sensed to determine coagulation conditions, and a gas flow cartridge wherein gas is passed through the fluid sample to transmit liquid in bubbles and the accumulation of the coagulating liquid from the bubbles is sensed to detect coagulation. An actuator mechanism operates with either one or both types of cartridges to create the conditions under which coagulation can be detected and to sense the coagulation detection conditions. The actuator mechanism reciprocates the plunger assembly and forces gas through the liquid sample to create the bubbles.

Abstract: A gas flow cartridge in which to conduct analytical coagulation tests on a sample of fluid such as blood includes a tube-like member and a resilient flexible membrane having a slit formed therethrough to divide the tube-like member into an upper reaction chamber in which the test takes place and into a lower reagent chamber which initially contains reagent to be mixed with the sample of liquid upon which the test is to be conducted. The contents of the reagent chamber are forced through the slit in the resilient flexible membrane due to the flexing of the membrane around the slit when pressure is applied. Once the reagent is in the reaction chamber with the sample of fluid, a flow of gas is forced upward through the slit in the membrane during the analytical test.

Abstract: Coagulation is detected in a fluid sample contained in either a gas flow cartridge or a plunger sensor cartridge, either one of which may be inserted in an actuator mechanism which has the capability of acting on either type of cartridge. Coagulation is detected in the gas flow cartridge by optically sensing the accumulation of coagulating liquid in a foam member at the top of the reaction chamber. In the plunger sensor cartridge, a plunger assembly is raised and released to descend through the sample of liquid in the bottom of the reaction chamber. The plunger assembly descends more slowly upon an increase in the viscosity of the fluid sample due to coagulation. Both cartridges include a lower reagent chamber, an upper reaction chamber, and means initially sealing and thereafter communicating the contents from the reagent chamber to the reaction chamber.

Abstract: A gas flow cartridge includes a tube-like member which defines a reaction chamber in which a pool of liquid is subjected to an analytical test. A coating of debubbling agent is applied to an area of the tube-like member above the reaction chamber. The debubbling agent collapses bubbles of noncoagulated fluid but allows bubbles of coagulated fluid to continue an upward movement above the area where the coating is applied. Coagulation is detected by sensing the coagulated bubbles moving upward in the tube-like member. A quantity of activator agent is initially confined with the reaction chamber, preferably within a structure defined by a segment of paper-like material formed into an activator retaining form. The paper-like material unrolls or unfolds during the analytical test.