Chemistry: analytical and immunological testing – Rate of reaction determination
Patent
1984-07-17
1988-03-15
Marcus, Michael S.
Chemistry: analytical and immunological testing
Rate of reaction determination
436103, 436105, 436164, G01N 2178, G01N 3352
Patent
active
047313315
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
1. Field of the Invention
The instant invention pertains to a method for assaying inorganic phosphorus and to a reagent for use therein.
2. Description of the Prior Art
The use of molybdate in the determination of inorganic phosphorus was first suggested by Woods et al (1). Woods et al found that under suitable conditions molybdates react with phosphates to form heteropoly compounds such as ammonium phosphomolybdate. These compounds absorb in the ultraviolet range or can be reduced, using any of a wide range of reducing agents under conditions which do not reduce the excess molybdate present, to form molybdenum blue which can be measured at wavelengths above 600 nm.
Until now, all methods for phosphorus determination on whole serum (i.e., serum which has not been deproteinized) have been performed by an end point technique (2-7). In the end point technique, an initial absorbance reading is first taken of the reagent alone, a sample to be assayed is then added to the reagent, and after equilibrium has been reached a second absorbance reading is taken. From this change in absorbance the phosphorus concentration is calculated.
With the advent of rate analyzers, attempts have been made to produce a rate method for phosphorus determinations. However, to date such attempts have not yielded a rate methodology. In fact, Daly et al (8) reported that "the possibility of an initial rate reaction was eliminated when it was discovered that serum protein had an accelerating effect on the reaction. This phenomena varied from serum to serum without affecting the final absorbance difference between the blank and the reaction product".
Accordingly, it would be very desirable to have a reagent capable of being employed in a rate determination of inorganic phosphorus in serum.
SUMMARY OF THE INVENTION
In accordance with the present invention there is provided a rate method for assaying inorganic phosphorus and a reagent for use therein. The reagent of this invention is of the type comprising an acid, a molybdate salt, a non-ionic surfactant, and polyvinylpyrrolidone (PVP). The reagent of this invention is characterized in that it further comprises an enhancing amount of at least one sugar alcohol.
The present invention also encompasses a method for assaying inorganic phosphorus. This method is of the type which comprises mixing a sample of biological fluid with a reagent and measuring the absorbance of the resulting solution. The method of the present invention is characterized in that the above reagent is employed therein. The method can further be characterized in that the measurement can be made via a rate technique.
Still other features and attendant advantages of the present invention will become apparent to those skilled in the art from a reading of the following detailed description of the preferred embodiments.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Preferably, the acid is selected from the group consisting of sulfuric acid, nitric acid, hydrochloric acid, citric acid, and mixtures thereof. More preferably the acid is sulfuric acid.
The salt moiety of the molybdate salt is preferably selected from the group consisting of ammonium, sodium, lithium, potassium, and mixtures thereof. More preferably, the salt moiety is ammonium.
Preferably, the non-ionic surfactant is selected from the group consisting of Triton X-100 (polyethylene glycerol-p-isooctylphenyl ether), Brij 35 (polyoxyethylene(23) lauryl ether), Tween 20 (polyoxyethylene(20) sorbitan monolaurate), Tween 80 (polyoxyethylene(20) sorbitan monooleate), and mixtures thereof. More preferably the non-ionic surfactant is Triton X-100 (polyethylene glycerol p-isooctylphenyl ether).
The sugar alcohol is preferably selected from the group consisting of D-mannitol, sorbitol, and mixtures thereof. More preferably, the sugar alcohol is D-mannitol.
The reagent can be prepared via any technique well known to those skilled in the art. It is preferred to employ a defoamer during such reagent preparation. One typical defoamer is butanol. But
REFERENCES:
patent: 3425805 (1969-02-01), Grobin
patent: 3547586 (1970-12-01), Denney et al.
patent: 3795484 (1974-03-01), Daly et al.
patent: 3853469 (1974-12-01), Morin et al.
patent: 3874853 (1975-04-01), Byrnes
patent: 3953359 (1976-04-01), Gindler
patent: 4009004 (1977-02-01), Hutchinson
patent: 4220451 (1980-09-01), Stefanchik
Ho et al., Anal. Biochem., vol. 60, pp. 413-416, 1974.
Allin et al, Biochim. Biophys. Acta, vol. 127, No. 1, pp. 521-523, 1966.
LeBel et al., Anal. Biochem., vol. 85, pp. 86-89, 1978.
Leigh et al., Anal. Biochem., vol. 106, pp. 279-284, 1980.
McCoy et al, Chemical Abstracts, vol. 97, Abstract No. 97:3105b, 1982.
Daly et al., Clin. Chem., vol. 18, No. 3, pp. 263-265, 1972.
Woods et al., Ind. Eng. Chem., vol. 13, No. 11, pp. 760-764, 1941.
Lundgren, Anal. Chem., vol. 32, No. 7, pp. 824-828, 1960.
Francis James H.
Shu Frank R.
Beckman Instruments Inc.
Grant Arnold
Hill Jr. Robert J.
Marcus Michael S.
May W. H.
LandOfFree
Rate method for the determination of inorganic phosphorus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Rate method for the determination of inorganic phosphorus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Rate method for the determination of inorganic phosphorus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1926418