Reagent for determination of leucocytes and measurement of haemoglobin in a sample of blood
The invention concerns a reagent for determination of leucocytes and measurement of haemoglobin in a sample of blood. This reagent comprises a buffer system that is suited to adjust selectively the pH of the reagent to an acidic value, at least one detergent of cationic type, a nitrogenous compound and, optionally, at least one inorganic salt. This reagent can be used in haematological analyses in human medicine and also permits the identification of a leucocytic subpopulation, in particular the basophil polymorphonuclear leucocytes.
1. A single reagent for the simultaneous determination of total leucocytes, and basophile polymorphonuolear leucocytes, and for the measurement of hemoglobin in a sample of blood, said reagent comprising:
a buffer suitable to adjust and maintain the pH to a value lower than 3;
at least one cationic detergent;
a nitrogenous compound, wherein said nitrogenous compound is a thiourea; and further comprising the absence of cyanic compounds.
2. The single reagent of claim 1 , wherein said buffer adjusts the pH to a value of 2.4.
3. The single reagent of claim 1 , wherein said buffer is a multi-component mixture selected from the group of mixtures consisting of:
potassium chloride plus hydrochloric acid,
tartaric acid plus sodium hydroxide,
citric acid plus sodium hydroxide,
potassium hydrogen phthalate plus hydrochloric acid,
citric acid plus disodium hydrogen phosphate, and
boric acid plus citric acid plus potassium dihydrogen phosphate.
4. The single reagent of claim 1 , wherein said detergent is selected from the group consisting of primary amines, acetates of fatty amines, hydrochlorides of fatty amines, quaternary ammonium salts, trimethylethylammonium bromide, and amides of cyclized diethylenetriamine.
5. The single reagent of claim 1 , wherein said detergent comprises amides of substituted diamines wherein said substituted diamines are canonized by a compound selected from the group consisting of ethyl sulfate, diethanolaminopropylamine, and diethylaminopropylamide.
6. The single reagent of claim 1 , wherein said thiourea is 1,3-dimethyl-2-thiourea.
7. The single reagent of claim 1 further comprising at least one inorganic salt.
8. The single reagent of claim 7 , wherein said at least one inorganic salt is an alkali metal salt.
9. The single reagent of claim 7 , wherein said at least one inorganic salt is a chloride or sulfate of sodium or potassium.
10. The single reagent of claim 1 , wherein said detergent is present at a concentration of 0.2–20 g/l and the nitrogenous compound is present at a concentration of 0.1–10 g/l.
11. The single reagent of claim 1 comprising:
5–10 g/l potassium chloride;
0.5–3 g/l 1,3-dimethyl-2-thiourea;
0.5–5 g/l dodecyltrimethylammonium chloride; and
1.0–10 g/l potassium hydrogen phosphate plus hydrochloric acid.