US3876502A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reagent formulations for assaying urea nitrogen in biological specimens and methods of preparing and using same
Assignee: Mallinckrodt Inc
•
Filing: 1974-05-06
•
Granted: 1975-04-08
•
Expires: 1994-05-06
Abstract
Abstract A solid, water-soluble substantially anhydrous, storage-stable reagent formulation for use in conducting a clinical diagnostic test on a biological specimen is provided. The reagent formulation comprises a mixture containing a reagent capable of participating in a test reaction to effect a measurable change in a test system; and a nitrogen bearing polyoxyalkylene nonionic surfactant. The surfactant has a structure corresponding to that obtained when ethylene diamine is reacted sequentially with propylene oxide and ethylene oxide in the presence of a catalyst. The polyoxypropylene chains of said surfactant have an average molecular weight of between about 750 and about 6750. Methods of preparing the reagent formulations and methods of using them to conduct clinical diagnostic tests are also provided.
Inventors
- 👤 Alexander A Monte
- 👤 Ching Chiang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:53
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/52; C; C12; C12Q; C12Q1/00; C12Q1/26; C12Q1/58; G01N33/72; G01N33/721
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
87 words
AN ENZYME REAGENT FORMULATION FOR USE IN ASSAYING A SPECIMEN FOR BLOOD UREA NITROGEN COMPRISING A SOLID, WATERSOLUBLE, SUBSTANTIALLY ANHYDROUS, STORAGE-STABLE MIXTURE CONTAINING (A) UREASE; (B) A SLT OF ETHYLENEDIAMINETETRAACETIC ACID; (C) A CARBOHYDATE POLYMER; (D) MANNITOL AND (E) A NITROGEN-CONTANING POLYOXYALKYLENE NONIONIC SURFACTANT HAVING A STRUCTURE CORRESPONDING TO THAT OBTAINED WHEN ETHYLENE DIAMINE IS REACTED SEQUENTIALLY WITH PROPYLENE OXIDE AND ETHYLENE OXIDE IN THE PRESENCE OF A CATALYST, THE POLYOXYPROPYLENE CHAINS OF SAID SURFACTANT HAVING AN AVERAGE MOLECULAR WEIGHT OF BETWEEN ABOUT 750 AND ABOUT 6750.
Claim 2
Dependent Claim
87 words
AN ENZYME REAGENT FORMULATION FOR USE IN ASSAYING A SPECIMEN FOR BLOOD UREA NITROGEN COMPRISING A SOLID, WATERSOLUBLE, SUBSTANTIALLY ANHYDROUS, STORAGE-STABLE MIXTURE CONTAINING (A) UREASE; (B) A SLT OF ETHYLENEDIAMINETETRAACETIC ACID; (C) A CARBOHYDATE POLYMER; (D) MANNITOL AND (E) A NITROGEN-CONTANING POLYOXYALKYLENE NONIONIC SURFACTANT HAVING A STRUCTURE CORRESPONDING TO THAT OBTAINED WHEN ETHYLENE DIAMINE IS REACTED SEQUENTIALLY WITH PROPYLENE OXIDE AND ETHYLENE OXIDE IN THE PRESENCE OF A CATALYST, THE POLYOXYPROPYLENE CHAINS OF SAID SURFACTANT HAVING AN AVERAGE MOLECULAR WEIGHT OF BETWEEN ABOUT 750 AND ABOUT 6750.
Claim 3
Dependent Claim
30 words
A reagent formulation as set forth in claim 1 wherein said nitrogen-containing surfactant is solid and the polyoxypropylene chains thereof have an average molecular weight of less than about 4000.
Claim 4
Dependent Claim
52 words
a chromogenic reagent formulation comprising a mixture containing: a. sodium salicylate; b. sodium nitroferricyanide; and c. said nitrogen-containing polyoxyalkylene nonionic surfactant; and 3. an enzyme reagent formulation comprising a mixture containing: a. urease; b. a salt of ethylenediaminetetraacetic acid; c. a carbohydrate polymer; d. mannitol; and e. said nitrogen-containing polyoxyalkylene nonionic surfactant;
Claim 5
Dependent Claim
52 words
a chromogenic reagent formulation comprising a mixture containing: a. sodium salicylate; b. sodium nitroferricyanide; and c. said nitrogen-containing polyoxyalkylene nonionic surfactant; and 3. an enzyme reagent formulation comprising a mixture containing: a. urease; b. a salt of ethylenediaminetetraacetic acid; c. a carbohydrate polymer; d. mannitol; and e. said nitrogen-containing polyoxyalkylene nonionic surfactant;
Claim 6
Independent Claim
90 words
The method of assaying a specimen for blood urea nitrogen using a plurality of solid, water-soluble, substantially anhydrous, storage-stable reagent formulations respectively comprising: 1. an alkaline chlorine reagent formulation comprising a mixture containing: a. sodium dichloroisocyanurate; b. lithium hydroxide; c. mannitol; and d. a nitrogen-containing polyoxyalkylene nonionic surfactant having a structure corresponding to that obtained when ethylenediamine is reacted sequentially with propylene oxide and ethylene oxide in the presence of a catalyst, the polyoxypropylene chains of said surfactant having an average molecular weight of between about 750 and about 6750;
Claim 7
Independent Claim
90 words
The method of assaying a specimen for blood urea nitrogen using a plurality of solid, water-soluble, substantially anhydrous, storage-stable reagent formulations respectively comprising: 1. an alkaline chlorine reagent formulation comprising a mixture containing: a. sodium dichloroisocyanurate; b. lithium hydroxide; c. mannitol; and d. a nitrogen-containing polyoxyalkylene nonionic surfactant having a structure corresponding to that obtained when ethylenediamine is reacted sequentially with propylene oxide and ethylene oxide in the presence of a catalyst, the polyoxypropylene chains of said surfactant having an average molecular weight of between about 750 and about 6750;
Claim 8
Dependent Claim
21 words
The method as set forth in claim 3 wherein said change is measured by determining the optical density of said system.
Claim 9
Dependent Claim
29 words
The method as set forth in claim 3 wherein said nitrogen-containing surfactant is solid and the polyoxypropylene chains thereof have an average molecular weight of less than about 4000.
Claim 10
Independent Claim
119 words
The method of preparing a solid, water-soluble, free-flowing, substantially anhydrous, storage-stable granular enzyme reagent formulation for use in assaying blood for urea nitrogen, said method comprising the steps of: 1. preparing a mixture containing: a. urease; b. a salt of ethylene diaminetetraacetic acid; c. a carbohydrate polymer; d. mannitol; e. a nitrogen-containing polyoxyalkylene nonionic surfactant having a structure corresponding to that obtained when ethylene diamine is reacted sequentially with propylene oxide and ethylene oxide in the presence of a catalyst, the polyoxypropylene chains of said surfactant having an average molecular weight of between about 750 and about 6750; and f. a solvent for said surfactant; and 2. removing the solvent to form a substantially anhydrous, free-flowing, water-soluble, granular solid.
Claim 11
Independent Claim
119 words
The method of preparing a solid, water-soluble, free-flowing, substantially anhydrous, storage-stable granular enzyme reagent formulation for use in assaying blood for urea nitrogen, said method comprising the steps of: 1. preparing a mixture containing: a. urease; b. a salt of ethylene diaminetetraacetic acid; c. a carbohydrate polymer; d. mannitol; e. a nitrogen-containing polyoxyalkylene nonionic surfactant having a structure corresponding to that obtained when ethylene diamine is reacted sequentially with propylene oxide and ethylene oxide in the presence of a catalyst, the polyoxypropylene chains of said surfactant having an average molecular weight of between about 750 and about 6750; and f. a solvent for said surfactant; and 2. removing the solvent to form a substantially anhydrous, free-flowing, water-soluble, granular solid.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-07 | 1978-10-07 | 1979-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-07 | 1982-10-07 | 1983-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-07 | 1986-10-07 | 1987-04-08 | $7700.00 | Window Closed / Lapsed |