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AssigneeMedtronic, Inc.
InventorsCharlene Yuan, Trevor C. Huang, Tessy Kanayinkal, Mary Jo Passenheim, Craig D. Petersen, Ivan Akunovich
Estimating the term…
High range activated clotting time (HR-ACT) tests detect blood clotting time in blood samples which have high levels of heparin. Reagents such as calcium chloride and kaolin within the test apparatus trigger clotting. The cartridge is treated with a strong surface treatment process, such as an atmospheric plasma treatment, to increase the hydrophilic property of the test chamber, there may be a significant reduction in the kaolin concentration required to activate the blood sample and initiate the coagulation process. The kaolin concentration may be further reduced if the buffer component used in the buffer saline contains phosphate. The reduction of the kaolin concentration allows more calcium to be released from the kaolin to participate in the clotting process. The combined effect of adding a surface treatment to the cartridge to increase the hydrophilic property of reaction chamber and adding phosphate into buffered saline allows for clot detection of blood samples containing 5˜6 U/mL heparin.
A cartridge for blood clot detection, comprising a test chamber having an interior, at least a portion of the interior having a hydrophilic surface upon which lies a composition comprising a first positively charged reagent reduced with a buffering agent and a second, negatively charged reagent.
A method of manufacturing a cartridge for measuring clotting time of a sample of blood introduced into a chamber within the cartridge, comprising forming the cartridge to have an interior hydrophilic surface upon which lies a composition comprising a first positively charged reagent reduced with a buffering agent and a second, negatively charged reagent.
A method of detecting formation of a clot in a blood sample with a washer moving through the sample, comprising:
A method of manufacturing a cartridge for measuring clotting time of a sample of blood introduced into a chamber within the cartridge, comprising providing the cartridge with an interior, treating at least a portion of the interior to have a water contact angle between about 20 and about 60 degrees, and providing onto the hydrophilic surface a composition comprising a first positively charged reagent reduced with a buffering agent and a second, negatively charged reagent.
Dependencies are inferred from the claim text.