The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 23, 1998
Filed:
Nov. 18, 1996
Jeffrey A Schuster, Oakland, CA (US);
Peter M Lloyd, Oakland, CA (US);
Igor Gonda, San Francisco, CA (US);
David Cipolla, Belmont, CA (US);
Aradigm Corporation, Hayward, CA (US);
Abstract
A device and method for the detection of small particles in a fluid. The device is a collapsible sample container having a opening which is covered, at least in part, by a porous membrane having a plurality (e.g., 100) of pores therein having a pore diameter equal to or smaller than the diameter of the particles to be detected (e.g., 01. to 100 microns). A means for collapsing the container to extrude the liquid sample through the membrane pores is provided along with a means for detecting pressure during the extrusion. The size and number of particles in the liquid is calculated by relating the extrusion pressure required to a pre-calibrated standard. When a constant pressure is applied the rate at which fluid is extruded decreases as the pores of the membrane become clogged with particles. The greater number of particles in the sample tested the greater the number of pores which will become clogged with particles which causes an increase in the amount of time or pressure needed to extrude a given volume of the sample through the porous membrane. The number of pores per unit area and pore size can be varied depending on the probable size and concentration of the particles in the liquid be tested.