Reagent for combined diluting and lysing whole blood

Claim 2

A reagent for combined diluting and lysing a whole blood sample for use in electronic enumeration of white blood cells and determination of hemoglobin concentration, comprising in an aqueous solution: (A) a quaternary ammonium salt detergent for lysing red blood cells in the sample; (B) at least one salt of an anion selected from the group consisting of sulfate, carbonate, formate, and acetate for preventing aggregation of platelets in said sample; and (C) an alkali metal cyanide for conversion of hemoglobin to a chromagen.

Claim 3

The reagent as claimed in claim 1 wherein said salt includes at least one cation selected from the group consisting of sodium, potassium, ammonium, magnesium, calcium, and tris(hydroxymethyl)aminomethyl.

Claim 4

The reagent as claimed in claim 1 wherein said salt is selected from the group consisting of sodium sulfate, potassium sulfate, ammonium sulfate, magnesium sulfate, calcium sulfate, and tris(hydroxymethyl)aminomethyl sulfate.

Claim 5

The reagent as claimed in claim 3 wherein the concentration of sulfate ion is in the range 30 to 180 mmole/liter.

Claim 6

The reagent as claimed in claim 3 wherein the concentration of sulfate ion is in the range 60-120 mmole/liter.

Claim 7

The reagent as claimed in claim 1 wherein said salt includes sodium sulfate.

Claim 8

The reagent as claimed in claim 6 wherein the concentration of sulfate ion is in the range 30 to 180 mmole/liter.

Claim 9

The reagent as claimed in claim 6 wherein the concentration of sulfate ion is in the range 60-100 mmole/liter.

Claim 10

The reagent as claimed in claim 1 wherein said salt includes at least one member selected from the group consisting of sodium carbonate, potassium carbonate, ammonium carbonate, magnesium carbonate, calcium carbonate, and tris(hydroxymethyl)aminomethyl carbonate.

Claim 11

The reagent as claimed in claim 1 wherein the concentration of said anion is in the range 30 to 180 mmole/liter.

Claim 12

The reagent as claimed in claim 1 wherein said cyanide includes potassium cyanide.

Claim 13

The reagent as claimed in claim 11 wherein said potassium cyanide concentration is in the range 0.005 to 0.65 g/liter.

Claim 14

The reagent as claimed in claim 1 further comprising phosphate buffering agent.

Claim 15

The reagent as claimed in claim 13 wherein said phosphate buffering agent includes a monobasic phosphate salt and a dibasic phosphate salt.

Claim 16

The reagent as claimed in claim 1 wherein said reagent has a pH in the range 7 to 11.

Claim 17

The reagent as claimed in claim 1 wherein said quaternary ammonium detergent includes at least one member selected from the group consisting of cetyldimethylethylammonium bromide and tetradecyltrimethylammonium bromide.

Claim 18

The reagent as claimed in claim 1 comprising the following components and the concentrations indicated per liter of the solution: ______________________________________ Component Concentration ______________________________________ Sodium Phosphate 0.037 g/l Monobasic Sodium Phosphate Dibasic 1.43 g/l Sodium Sulfate 14.3 g/l Polyethoxylated Alkyl Phenol 0.72 g/l Cetyldimethylethylammonium 1.1 g/l Bromide Sodium Nitrite 0.017 g/l Sodium Nitroferricyanide 0.01 g/l Potassium Cyanide 0.05 g/l ______________________________________

Claim 19

A reagent for combined diluting and lysing a whole blood sample for use in electronic enumeration of white blood cells and determination of hemoglobin concentration, free from EDTA and consisting essentially of the following components in an aqueous solution: (A) a quaternary ammonium salt detergent for lysing red blood cells in the sample; (B) at least one salt of an anion selected from the group consisting of sulfate, carbonate, formate, and acetate for preventing aggregation of platelets in said sample; and (C) an alkali metal cyanide for conversion of hemoglobin to a chromagen.

Claim 20

A reagent for combined diluting and lysing a whole blood sample for use in electronic enumeration of white blood cells and determination of hemoglobin concentration, free from EDTA and consisting essentially of the following components in an aqueous solution: (A) a quaternary ammonium salt detergent for lysing red blood cells in the sample; (B) at least one salt of an anion selected from the group consisting of sulfate, carbonate, formate, and acetate for preventing aggregation of platelets in said sample; and (C) an alkali metal cyanide for conversion of hemoglobin to a chromagen.

Claim 21

The reagent as claimed in claim 18 wherein said salt includes at least one cation selected from the group consisting of sodium, potassium, ammonium, magnesium, calcium, and tris(hydroxymethyl)aminomethyl.

Claim 22

The reagent as claimed in claim 18 wherein said salt is selected from the group consisting of sodium sulfate, potassium sulfate, ammonium sulfate, magnesium sulfate, calcium sulfate, and tris(hydroxymethyl)aminomethyl sulfate.

Claim 23

The reagent as claimed in claim 20 wherein the concentration of sulfate ion is in the range 30 to 180 mmole/liter.

Claim 24

The reagent as claimed in claim 20 wherein the concentration of sulfate ion is in the range 60-120 mmole/liter.

Claim 25

The reagent as claimed in claim 18 wherein said salt includes sodium sulfate.

Claim 26

The reagent as claimed in claim 23 wherein the concentration of sulfate ion is in the range 30 to 180 mmole/liter.

Claim 27

The reagent as claimed in claim 23 wherein the concentration of sulfate ion is in the range 60-100 mmole/liter.

Claim 28

The reagent as claimed in claim 18 wherein said salt includes at least one member selected from the group consisting of sodium carbonate, potassium carbonate, ammonium carbonate, magnesium carbonate, calcium carbonate, and tris(hydroxymethyl)aminomethyl carbonate.

Claim 29

The reagent as claimed in claim 18 wherein the concentration of said anion is in the range 30 to 180 mmole/liter.

Claim 30

The reagent as claimed in claim 18 wherein said cyanide includes potassium cyanide.

Claim 31

The reagent as claimed in claim 28 wherein said potassium cyanide concentration is in the range 0.005 to 0.65 g/liter.

Claim 32

The reagent as claimed in claim 18 further including phosphate buffering agent.

Claim 33

The reagent as claimed in claim 30 wherein said phosphate buffering agent includes a monobasic phosphate salt and a dibasic phosphate salt.

Claim 34

The reagent as claimed in claim 18 wherein said reagent has a pH in the range 7 to 11.

Claim 35

The reagent as claimed in claim 18 wherein said quaternary ammonium detergent includes at least one member selected from the group consisting of cetyldimethylethylammonium bromide and tetradecyltrimethylammonium bromide.

Claim 36

The reagent as claimed in claim 18 consisting essentially of the following components and the concentrations indicated per liter of the solution: ______________________________________ Component Concentration ______________________________________ Sodium Phosphate 0.037 g/l Monobasic Sodium Phosphate Dibasic 1.43 g/l Sodium Sulfate 14.3 g/l Polyethoxylated Alkyl Phenol 0.72 g/l Cetyldimethylethylammonium 1.1 g/l Bromide Sodium Nitrite 0.017 g/l Sodium Nitroferricyanide 0.01 g/l Potassium Cyanide 0.05 g/l ______________________________________