NOTES ON THE DETERMINATION OF SERUM INORGANIC PHOSPHATE AND SERUM PHOSPHATASE ACTIVITY

Abstract The merits of the vanadomolybdate method in the determination of inorganic phosphate are highly underestimated with regard to the simplicity of the method and the stability of both the reagents and the color that is formed. The absorption curve of the phosphovanadomolybdate complex, with its maximum at 335 nm, extends into the visible range of the spectrum. This permits measurements with inexpensive tungsten-lamp colorimeters. On-stream dialysis is best done in a nitric acid medium, 0.15 mol/liter. Paralleled by the change in the H2PO4-/H3PO4 ratio, appreciable protein binding and poor dialysis efficiency are seen at lower acid concentrations (pH greater than 1.0). Optimum reaction-mixture concentrations of vanadium and molybdenum appeared to be respectively 0.2 and 5 mmol/liter up to 3 mmol of phosphate per liter, in a final acid medium of 0.2 mol/liter, concentrations considerably lower than those used in some studies published earlier. Color development with the stable combined reagent is complete after only 20 s at room temperature and the color is stable for at least 2 h. Figures on precision and accuracy demonstrate the reliability of the method.

Download Full-text

Serum Inorganic Phosphate and Alkaline Phosphatase Activity in Cold-Exposed Rat

TAJ Journal of Teachers Association ◽

10.3329/taj.v19i1.3162 ◽

2011 ◽

Vol 19 (1) ◽

pp. 13-17

Author(s):

Md Shahidul Haque ◽

Zerin Fahmida Shima

Keyword(s):

Alkaline Phosphatase ◽

Phosphatase Activity ◽

Alkaline Phosphatase Activity ◽

Cold Exposure ◽

Inorganic Phosphate ◽

Alp Activity ◽

Significant Change ◽

Serum Inorganic Phosphate

To characterize serum constituents in blood in response to cold exposure, we measured serum inorganic phosphate (Pi) and alkaline phosphatase (ALP) levels. After 30 min exposure of cold, the serum Pi and alkaline phosphatase levels were 3.4 ± 0.06 mg/l and 72.33 ± 0.45 μmole/l respectively where as the control levels of these constituents are 3.05 ± 0.03 mg/l and 84 μmole/l respectively. Cold exposure for 30 min induces serum Pi concentration by 11.5 % and decreases ALP levels significantly by 13.9 % compared to control rats. Serum Pi for 1 h and 2 h were 3.8 mg/l and 4.17 ± 0.16 mg/l while ALP levels were 57.33 ± 0.88 μmole/l and 91 ± 1.73 μmole/l respectively in different groups of rats. Cold exposure stimulates serum Pi by 24.6 % and 36.7 % and reduces ALP activity by 31.7 % significantly and without significant change for 1 h and 2 h respectively. Another groups of rats exposed to cold for 4 h had Pi and ALP levels 4.66 ± 0.88 mg/l and 85.66 ± 0.88 μmole/l respectively. Cold exposure similarly stimulates Pi content significantly by 52.8 % without affecting ALP activity compared to the control rather reaches to basal level. Our results demonstrate that Pi and ALP levels in cold-exposed rats are regulated in different ways. doi: 10.3329/taj.v19i1.3162 TAJ 2006; 19(1):13-17

Download Full-text

Automated Determination of Serum Alkaline Phosphatase Using a Modified Bodansky Technic

Clinical Chemistry ◽

10.1093/clinchem/10.1.75 ◽

1964 ◽

Vol 10 (1) ◽

pp. 75-82 ◽

Cited By ~ 6

Author(s):

H Keay ◽

J A Trew

Keyword(s):

Alkaline Phosphatase ◽

Enzyme Activity ◽

Phosphatase Activity ◽

Alkaline Phosphatase Activity ◽

Inorganic Phosphate ◽

Serum Alkaline Phosphatase ◽

Automated Determination

Abstract An automated procedure for the measurement of alkaline phosphatase activity by a modification of the Bodansky method is described. It has been possible to adapt the Fiske-SubbaRow method for phosphate so that alkaline phosphatase is determined by a second run, immediately following the determination of inorganic phosphate. Studies of the effect of time, pH, and concentration of barbital on the enzyme activity are discussed, and the advantages of the method are listed.

Download Full-text

Assay of Serum Inorganic Phosphate without Deproteinisation: Automated and Manual Micromethods

Annals of Clinical Biochemistry International Journal of Laboratory Medicine ◽

10.1177/000456327401100168 ◽

1974 ◽

Vol 11 (1-6) ◽

pp. 234-237 ◽

Cited By ~ 38

Author(s):

R. Lawrence

Keyword(s):

Inorganic Phosphate ◽

Sodium Lauryl Sulphate ◽

Good Precision ◽

Molybdenum Blue ◽

Blue Reaction ◽

Serum Inorganic Phosphate

Several current techniques for the determination of serum inorganic phosphate in the presence of proteins are shown to have important disadvantages. An improved manual micromethod is described in which proteins are kept in solution by the use of sodium lauryl sulphate and the phosphate determined by the molybdenum blue reaction. The procedure has been adapted for the Technicon AutoAnalyzer and the Vickers D-300 and M-300, and has been shown to give very good precision in routine use.

Download Full-text

Determination of Serum Inorganic Phosphate

Practical Textbook of Biochemistry for Medical Students ◽

10.5005/jp/books/12054_28 ◽

2013 ◽

pp. 74-74

Author(s):

DM Vasudevan ◽

Subir Das

Keyword(s):

Inorganic Phosphate ◽

Serum Inorganic Phosphate

Download Full-text

Error introduced by specimen handling before determination of inorganic phosphate concentrations in plasma and serum.

Clinical Chemistry ◽

10.1093/clinchem/22.11.1909 ◽

1976 ◽

Vol 22 (11) ◽

pp. 1909-1911 ◽

Cited By ~ 5

Author(s):

J E Carothers ◽

N M Kurtz ◽

J Lemann

Keyword(s):

Coefficient Of Variation ◽

Inorganic Phosphate ◽

Room Temperature ◽

Processing Technique ◽

Healthy Adults ◽

Blood Sampling ◽

Specimen Handling ◽

Evacuated Tubes ◽

Serum Inorganic Phosphate

Abstract Values for serum inorganic phosphate (Pi) concentrations in groups of healthy adults vary widely, the coefficient of variation ranging from 10 to 15%. We undertook to determine in 23 healthy adults whether part of this variation could be accounted for by (a) drawing blood in syringes vs. evacuated tubes (b) the time between blood sampling and separation of serum or plasma, and (c) the prevention of clotting. Values were unaffected by a, decreased significantly with time at room temperature between blood sampling and separation of cells in both serum and plasma, and were significantly lower in plasma than in serum. The group coefficient of variation for Pi averaged 13% and was uninfluenced by the blood-processing technique.

Download Full-text