Method and apparatus for monitoring alteration of flow characteristics in a liquid sample
First Claim
1. A device for measuring blood coagulation time, comprising:
- (a) a first substrate;
(b) a second substrate;
(c) a spacer layer disposed between the first and second substrates, said spacer layer having an opening formed therein defining a sample receiving chamber, a vented sink chamber, and an elongated reservoir forming a conduit for liquid movement between the sample receiving chamber and the sink chamber;
(d) a first electrode disposed on the first substrate, said first electrode being exposed through the reservoir portion of the opening in the spacer layer; and
(e) a second electrode disposed on the second substrate, said second electrode being exposed through the reservoir portion of the opening in the spacer layer;
wherein the first and second electrodes are in electrically conductive contact with the elongated reservoir such that an electrical signal can be detected between the first and second electrodes when a conductive liquid sample is disposed in the reservoir and at least one of the electrodes is electrically insulated from the sample receiving chamber and from the sink chamber, wherein the relative sizes of the reservoir, the sink, and a region at the connection of the reservoir and the sink are such that the time required for emptying sample from the reservoir to occur in the absence of coagulation is greater than the time required for coagulation to occur, and wherein the vented sink chamber is vented to the atmosphere; and
(f) first and second contact leads extending from the first and second electrodes, respectively, for connection of the device to an apparatus for measuring an electrochemical signal between the first and second electrodes through a sample in the reservoir.
6 Assignments
0 Petitions
Accused Products
Abstract
A device for measuring blood coagulation time is formed from a first substrate; a second substrate; a spacer layer disposed between the first and second substrates, said spacer layer having an opening formed therein defining a sample receiving chamber, a vented sink chamber, and an elongated reservoir forming a conduit for liquid movement between the sample receiving chamber and the sink chamber; a first electrode disposed on the first substrate, said first electrode being exposed in the reservoir portion through a first opening in the spacer layer; and a second electrode disposed on the second substrate, said second electrode being exposed in the reservoir portion through a second opening in the spacer layer. The device of the invention is used in combination with an apparatus that is connected to the first and second electrodes for measuring current flow between the first and second electrodes. Changes in observed current are indicative of flow through the device, and a cessation of flow indicates coagulation.
-
Citations
25 Claims
-
1. A device for measuring blood coagulation time, comprising:
-
(a) a first substrate; (b) a second substrate; (c) a spacer layer disposed between the first and second substrates, said spacer layer having an opening formed therein defining a sample receiving chamber, a vented sink chamber, and an elongated reservoir forming a conduit for liquid movement between the sample receiving chamber and the sink chamber; (d) a first electrode disposed on the first substrate, said first electrode being exposed through the reservoir portion of the opening in the spacer layer; and (e) a second electrode disposed on the second substrate, said second electrode being exposed through the reservoir portion of the opening in the spacer layer; wherein the first and second electrodes are in electrically conductive contact with the elongated reservoir such that an electrical signal can be detected between the first and second electrodes when a conductive liquid sample is disposed in the reservoir and at least one of the electrodes is electrically insulated from the sample receiving chamber and from the sink chamber, wherein the relative sizes of the reservoir, the sink, and a region at the connection of the reservoir and the sink are such that the time required for emptying sample from the reservoir to occur in the absence of coagulation is greater than the time required for coagulation to occur, and wherein the vented sink chamber is vented to the atmosphere; and (f) first and second contact leads extending from the first and second electrodes, respectively, for connection of the device to an apparatus for measuring an electrochemical signal between the first and second electrodes through a sample in the reservoir. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
-
-
18. A method for determining coagulation time of a blood sample, comprising the steps of:
-
(a) introducing a blood sample into a device for measuring blood coagulation time wherein the sample is combined with a reagent effective to promote coagulation of blood disposed to contact a blood sample introduced to the sample receiving chamber in the device, said device comprising; a first substrate; a second substrate; a spacer layer disposed between the first and second substrates, said spacer layer having an opening formed therein defining a sample receiving chamber, a vented sink chamber, and an elongated reservoir forming a conduit for liquid movement between the sample receiving chamber and the sink chamber; a first electrode disposed on the first substrate, said first electrode being exposed through the reservoir portion of the opening in the spacer layer; and a second electrode disposed on the second substrate, said second electrode being exposed through the reservoir portion of the opening in the spacer layer, wherein the first and second electrodes are in electrically conductive contact with the elongated reservoir such that an electrical signal can be detected between the first and second electrodes when a conductive liquid sample is disposed in the reservoir and at least one of the electrodes is electrically insulated from the sample receiving chamber and from the sink chamber, wherein the relative sizes of the reservoir, the sink, and a region at the connection of the reservoir and the sink are such that the time required for emptying sample from the reservoir to occur in the absence of coagulation is greater than the time required for coagulation to occur, and wherein the vented sink chamber is vented to the atmosphere, (b) measuring current between the first and second electrodes, and (c) determining from the change in measured current a coagulation time. - View Dependent Claims (19, 20, 21, 22, 23, 24)
-
-
25. A combination comprising
(a) a device for measuring blood coagulation time, comprising: -
a first substrate; a second substrate; a spacer layer disposed between the first and second substrates, said spacer layer having an opening formed therein defining a sample receiving chamber, a vented sink chamber, and an elongated reservoir forming a conduit for liquid movement between the sample receiving chamber and the sink chamber; a first electrode disposed on the first substrate, said first electrode being exposed through the reservoir portion of the opening in the spacer layer; and a second electrode disposed on the second substrate, said second electrode being exposed through the reservoir portion of the opening in the spacer layer, wherein the first and second electrodes are in electrically conductive contact with the elongated reservoir such that an electrical signal can be detected between the first and second electrodes when a conductive liquid sample is disposed in the reservoir and at least one of the electrodes is electrically insulated from the sample receiving chamber and from the sink chamber, wherein the relative sizes of the reservoir, the sink, and a region at the connection of the reservoir and the sink are such that the time required for emptying sample from the reservoir to occur in the absence of coagulation is greater than the time required for coagulation to occur, and wherein the vented sink chamber is vented to the atmosphere; and first and second contact leads extending from the first and second electrodes, respectively, for connection of the device to an apparatus for measuring an electrochemical signal between the first and second electrodes through a sample in the reservoir; and (b) an apparatus connected to the first and second electrodes for measuring current flow between the first and second electrodes, said apparatus comprising connectors configured to connect to the first and second contact leads, a signal processor for converting a current signal to an indication of coagulation time, and means for communicating the indication of coagulation time to a user.
-
Specification