Apparatus and method for assaying coagulation in fluid samples

A cartridge adapted for use with an analyzer for assaying an enzyme in a fluid sample comprising:

• a housing having a sample entry port, overflow chamber, holding chamber, and an analysis location containing a hydrophobic area in part,
• an airtight entry port closure,
• a pump actuated by the analyzer for moving the sample within the cartridge,
• one or more reagent deposits in the analysis location comprising at least one substrate capable of reaction with an enzyme in the fluid sample, the reaction of the enzyme forming a detectable reaction product,
• a first sensor for detecting the location of the fluid sample, and
• a second sensor for detecting the detectable reaction product.

A single-use cartridge used in combination with an analyzer for determining a coagulation parameter of a sample of blood or blood derivative, comprising;

• a cartridge which includes an entry port for receiving a sample, an entry port closure, a holding chamber in communication at a first end with the entry port, and a capillary stop in communication with the holding chamber at a second end, the capillary stop also in communication with an analysis chamber,
• the holding chamber in communication with an overflow chamber for receiving and retaining excess sample,
• the overflow chamber in communication with a pneumatic pump actuated by the analyzer,
• the analyzer actuating the pneumatic pump to displace sample in the holding chamber through the capillary stop into the analysis chamber to deliver a metered portion of the sample into the analysis chamber,
• the analysis chamber containing a substrate for the enzyme thrombin capable of dissolving in the metered sample, an amperometric sensor for detecting the product of the reaction between thrombin and the substrate, and a conductimetric sensor for detecting the position of the sample in the analysis chamber,
• the amperometric sensor and the conductimetric sensor connected to the analyzer for providing output signals to the analyzer,
• the analyzer capable of using the output signal of the conductimetric sensor to actuate the pneumatic pump to control the position of the sample in the analysis chamber,
• the analyzer capable of determining the coagulation parameter from the output signal of the amperometric sensor, and
• the cartridge containing a hydrophobic area between the capillary stop and the analysis chamber to prevent sample in the analysis chamber from being drawn back into the holding chamber.

A cartridge for delivering a fluid sample to an analysis location comprising:

• a housing having a closable sample entry port for receiving a fluid sample;
• a holding chamber having a first end in communication with the entry port, the holding chamber having a second end with a capillary stop;
• wherein the analysis location is in communication with the capillary stop and comprising a pre-sensor chamber between the capillary stop and the analysis location, further comprising a hydrophobic area between the analysis location and the pre-sensor chamber;
• and
• wherein the capillary stop selectively allows passage of the sample from the holding chamber to the analysis location;
• an overflow chamber, in communication with the holding chamber for handling overflow of incoming sample;
• and
• a pump for providing a force to the fluid sample in the holding chamber, thereby allowing passage of the sample through the capillary stop.

A cartridge for delivering a fluid sample to an analysis location comprising:

• a housing having a closable sample entry port for receiving a fluid sample;
• a holding chamber having a first end in communication with the entry port, the holding chamber having a second end with a capillary stop;
• wherein the analysis location is in communication with the capillary stop;
• and wherein the capillary stop selectively allows passage of the sample from the holding chamber to the analysis location;
• an overflow chamber in communication with the holding chamber, for handling overflow of incoming sample;
• and
• a pump in fluidic connection with the overflow chamber for providing a force to the fluid sample in the holding chamber, thereby allowing passage of the sample through the capillary stop.

A cartridge for delivering a fluid sample to an analysis location comprising:

• a housing having a closable sample entry port for receiving a fluid sample;
• a holding chamber having a first end in communication with the entry port, the holding chamber having a second end with a capillary stop;
• wherein the analysis location is in communication with the capillary stop;
• and wherein the capillary stop selectively allows passage of the sample from the holding chamber to the analysis location;
• an overflow chamber in communication with the holding chamber which is above and in fluid communication with the holding chamber and separated by a holding chamber wall, for handling overflow of incoming sample;
• and
• a pump for providing a force to the fluid sample in the holding chamber, thereby allowing passage of the sample through the capillary stop.