Chemistry: analytical and immunological testing – Metal or metal containing – Present in biological fluids
Patent
1986-05-06
1988-04-05
Schor, Kenneth M.
Chemistry: analytical and immunological testing
Metal or metal containing
Present in biological fluids
436 84, 436165, 436177, 436179, 436808, 436910, 422 57, 422 58, 422 61, G01N 3320
Patent
active
047359048
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
This invention relates to the measurement of total iron binding capacity in serum.
Iron is carried in the blood plasma by a specific carrier protein called transferrin. This is a protein of molecular weight 76,000-80,000, which has two sites each capable of binding one iron atom. The total amount of transferrin present determines the total iron binding capacity (T.I.B.C.) of the serum.
The estimation of the T.I.B.C. is an important clinical procedure, with an established role in the diagnosis of such conditions as iron deficiency anaemia and haemochromatosis, and in the monitoring of therapeutic procedures. In iron deficiency states, T.I.B.C. is elevated: in iron overload conditions T.I.B.C. is depressed.
Techniques which are currently used for determination of T.I.B.C. rely on the saturation of transferrin and removal of excess iron from the serum with an adsorbent such as magnesium carbonate (Ramsay, W. N. M.: Clin. Chim. Acta 2 221 (1957)) or an ion exchange resin (Peters, T., Giovanello T. J., Apt, L. and Ross, J. R.; J. Lab. Clin. Med. 48 274 (1956)). Other methods employ direct measurement of the excess iron after saturation, and calculation of unsaturated iron-binding capacity (Williams, H. L., and Conrad, M. E.; J. Lab. Clin. Med. 67 171 (1966); O'Malley, J. A., Hassan, A., Shiley, J., and Traynor, H.; Clin. Chemistry 16 92 (1970)). The most commonly used magnesium carbonate method is subject to error owing to the inclusion of non-transferrin bound iron in the supernatant solution (Ramsay, W. N. M.; J. Clin. Pathol. 26 691 (1973)).
An improved method using an alumina column, which was faster and simpler than the magnesium carbonate method while offering improved accuracy, was previously disclosed by the present inventor (Clin. Chemistry 26 156 (1980)).
SUMMARY AND OBJECTS OF THE INVENTION
The object of the present invention is to provide improvements in the measurement of T.I.B.C.
There is provided in accordance with the invention a tube closed at one end, having a removable closure, the tube containing a measured quantity of a dried iron-saturating substance, which is adhered to the inner surface of the base of the tube, and a measured quantity of dried alumina (aluminum oxide, Al.sub.2 O.sub.3).
Preferably the tube and closure are made of plastics.
Preferably the neck of the plastic tube is threaded to receive a plastics screw cap. The screw cap is most preferably large enough to contain the quantity of alumina.
Preferably the tube is made of polystyrene, most preferably of transparent polystyrene.
Preferably the cap is made of polyethylene.
The dried iron-saturating substance is preferably a complex salt of ferric iron.
The alumina is preferably basic chromatographic grade alumina, most preferably Brockmann grade II.
Preferably the tube is designed to fit sample carriers of automatic analysers such that their sample probes will sample from above the level occupied by alumina in the tube.
According to a further aspect of the invention, there is provided a method of performing the measurement of T.I.B.C. using the apparatus described hereinabove comprising pouring alumina out of the tube into the cap, adding a solvent, for example water, to the tube to dissolve the iron-saturating substance, and adding the sample of serum to the tube; then after a brief period of incubation to allow the iron to bind to transferrin in the serum sample, replacing the alumina in the tube, mixing the tube to allow binding of the unbound iron to the alumina, and after allowing the alumina to settle, measuring the iron content of the supernatant by any suitable means, for example by automatic continuous flow analyser or by atomic absorption spectroscopy.
BRIEF DESCRIPTION OF THE FIGURES OF THE DRAWING
Preferred embodiments of the invention will now be described by way of example only with reference to the accompanying drawings in which:
FIG. 1 represents an exploded view of a free-standing sample tube having a screw cap, containing a measured amount of alumina powder, and having a meas
REFERENCES:
patent: 900122 (1975-08-01), Dichter
patent: 3537822 (1970-11-01), O'Malley et al.
patent: 3773467 (1973-11-01), Yang et al.
patent: 3887332 (1975-06-01), Jakase et al.
patent: 3925020 (1975-12-01), Ogawa et al.
patent: 4224034 (1980-09-01), Denney et al.
patent: 4227620 (1980-10-01), Conway
patent: 4233031 (1980-11-01), Matson et al.
patent: 4272478 (1981-06-01), Vikho
patent: 4308027 (1981-12-01), Ceriotti
patent: 4434235 (1984-02-01), Rabi et al.
patent: 4522923 (1985-06-01), Deutsch et al.
patent: 4567150 (1986-01-01), Tabacco et al.
patent: 4588695 (1986-04-01), Takano et al.
patent: 4608231 (1986-08-01), Witty et al.
patent: 4624929 (1986-11-01), Ullman
Ramsay, W. N. M., The Determination of the Total Iron Binding Capacity of Serum. Clin. Chim. Acta 2, 221, (1957).
Peters, T., Giovanniello, T. J., Apt. L., and Ross, J. R., A New Method for the Determination of Serum Iron Binding Capacity, J. Lab. Clin. Med. 48, 274, (1956).
Williams, H. L., and Conrad, M. E., A One-Tube Method for Measuring the Serum Iron Concentration and Unsaturated Iron Binding Capacity, J. Lab. Clin. Med. 67, 171, (1966).
Starr, R. T., Use of an Alumina Column in Estimating Total Iron-Binding Capacity. Clin. Chem. 26, 156, (1980).
Ramsay, W. N. M., The Measurement of Serum Transferrin by Iron-Binding Capacity, J. Clin. Pathol. 26, 691, (1973).
Cook, J. D., An Evaluation of Adsorption Methods for Measurement of Plasma Iron-Binding Capacity, J. Lab. Clin. Med. 76, 497, (1970).
Dixon, K., Routine Clinical Measurement of Transferrin in Human Serum. Ann Clin Biochem. 10, 127, (1973).
Klein, B., Lucas, L. B., Searey, L., Application of Fe (II)-5-Pyridyl Benzediazepin-2- ones to the Determination of Serum Iron and Iron-Binding Capacity. Clin. Chim. Acta 26, 517, (1969).
Whicher, J. T., Blow, C., Formulation of Optimal Conditions for an Immunonephelometric Assay. Ann Clin. Biochem 17, 170, (1980).
Bandi, Z. L., Schoen, I., Bee, D., Immunochemical Methods for Measurement of Transferrin in Serum. Effects of Analytical Errors and Inappropriate Reference Intervals on Diagnostic Utility. Clin. Chem. 31, 1601, (1985).
International Committee for Standardization in Haematology., The Measurement of Total and Unsaturated Iron-Binding Capacity in Serum. British Journal of Haematology 38, 281, (1978).
Cody Lori-Ann
Schor Kenneth M.
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