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:
Nov. 06, 1990
Filed:
Dec. 16, 1987
James D Lapicola, Martinez, CA (US);
Hematology Marketing Associates, Inc., Plano, TX (US);
Abstract
A universal blood diluent for use in hematology analysis is the subject of this invention. The diluent consists of an aqueous solution of 0.4-1.5% by weight of either Na.sub.2 SO.sub.4 or NaNO.sub.3 or a combination of the two. Also included is 0.1-0.4% by weight of a salt of the formula XH.sub.2 PO.sub.4 where X is either Na or K and 0.1-2.4% by weight of a salt of the formula X.sub.2 HPO where X is Na or K. The phosphate salts may be hydrous or anhydrous. A mixture of Na and K phosphate salts may also been employed. The salts should be present in a ratio of from 1:1 to 1:6 (by weight), XH.sub.2 PO.sub.4 :X.sub.2 HPO.sub.4. 0.1 to 1% by weight of one or both of NaCl and KCl is also included. The Na.sub.2 SO.sub.4 and NaNO.sub.3 should be present in a ratio of at least 1:1 (by weight) relative to the chloride salt. The pH of the diluent should be within the range of 6.0-8.0 and it should have an osmotic strength of 200-400 milliosmoles. The diluent may be used in either automated or semi-automated analytical equipment. The use of an inorganic buffer offers numerous advantages over prior art organic buffers including cost an better performance. The diluent allows for leukocyte analysis as well as maintaining erythrocyte morphology until a lysing reagent is introduced.