Patent · US Expired

Method and apparatus for determining coagulation times

US3963349A · kind A · utility

46Cited by
2References
40Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 27, 1974
Grant dateJun 15, 1976
Priority date
Expiry dateAug 27, 1994

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N35/025
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A method and apparatus for determining coagulation times in such clinical laboratory procedures as prothrombin time tests, activated partial thromboplastin time tests, fibrinogen determinations, factor assays for specific blood coagulation factors, and the like. A fibrous filament is drawn at a predetermined rate through a small body of liquid to be tested and the interval, from the time a suitable coagulating agent is mixed with the liquid to the time the body of liquid clings to the filament and moves with it, is precisely measured as a direct indication of actual coagulation time. The liquid body is supported upon a non-wettable inclined surface bordered by walls defining a well for receiving the liquid and a pathway for its movement. Particularly effective results are achieved by utilizing a pair of spaced filaments moving at precisely the same rate, the filaments being bridged by a web or mass of clotted liquid when coagulation occurs. A photodetector senses movement of the clot and a timer automatically measures the time between coagulant addition and clot formation. After clot detection occurs, an arm lifts the paired filaments from the well while at the same time directing …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.