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Clinical Chemistry 48: 161-166, 2002;
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(Clinical Chemistry. 2002;48:161-166.)
© 2002 American Association for Clinical Chemistry, Inc.

Direct Serum Total Iron-binding Capacity Assay Suitable for Automated Analyzers

Gordon Siek1a, Joseph Lawlor1, Donna Pelczar1, Meena Sane1 and Joseph Musto1,2

1 Reference Diagnostics, Inc., 19 Crosby Dr., Suite 30, Bedford, MA 01730.

2 Diagnostic Laboratory Medicine, Inc., 14 Crosby Dr., Bedford, MA 01730.

aAuthor for correspondence. Fax 781-276-9002; e-mail gsiek{at}ref-dx.com.


   Abstract
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 Abstract
Introduction
 Materials and Methods
 Results
 Discussion
 References
 
Background: Present methods for measuring serum total iron-binding capacity (TIBC) involve manipulation of samples or performance of two assays on each sample. We developed a direct automated assay (DTIBC) for TIBC.

Methods: We added to serum a saturating amount of iron bound to an excess of chelating dye at a low pH, recorded a blank reading that represented the sum of the saturating amount of iron plus the serum iron, and then added a strong neutral pH buffer. The decrease in absorbance (as transferrin extracts iron from the iron-dye complex) is directly proportional to the TIBC. TIBC values for 125 patients were determined by DTIBC, alumina column TIBC (AC), magnetic particle TIBC (MTIBC), and the UIBC method (UIBC) on Roche COBAS FARA and Mira chemistry analyzers. In a separate study, TIBC values for 128 patients were determined on an Olympus AU400 by the DTIBC and the MTIBC methods.

Results: Methods comparisons on the COBAS analyzers yielded the following results: DTIBC = 1.05(MTIBC) - 1.0 µmol/L (r = 0.987; Sy|x = 2.6 µmol/L); DTIBC = 1.07(AC) - 1.0 µmol/L (r = 0.982; Sy|x = 3.0 µmol/L); and DTIBC = 1.14(UIBC) + 3.4 µmol/L (r = 0.982; Sy|x = 3.0 µmol/L). A similar correlation study using the Olympus AU400 yielded DTIBC = 1.00(MTIBC) - 0.1 µmol/L (r = 0.983; Sy|x = 2.7 µmol/L). The assay was linear from 12.5 to 125 µmol/L (70–700 µg/dL) TIBC on the COBAS FARA. Within- and between-run imprecision (CV) was <=4.8% at two concentrations. Plasma samples were unsuitable for the method. No interference was seen with common interferants other than ascorbate, deferoxamine, and ferrous sulfate, and only at concentrations well above normal.

Conclusion: The new DTIBC assay is suitable for routine use in clinical laboratories and may improve the quality of iron metabolism studies.


   Introduction
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 Abstract
 Introduction
Materials and Methods
 Results
 Discussion
 References
 
The serum total iron-binding capacity (TIBC) represents the maximum concentration of iron that can be bound by an individual’s serum protein. Determination of TIBC is one of several commonly used assays in the assessment of iron status (1)(2), and TIBC is highly correlated with serum transferrin, the primary serum iron transport protein, because >95% of serum nonheme iron is bound by transferrin (1)(2). Usually, only ~30% of the available serum iron-binding sites are occupied, and changes in the ratio of serum iron to TIBC (calculated as the percentage of transferrin saturation) reflect changes in the body iron stores (1)(2). Clinically, TIBC determinations are useful in the diagnosis of iron-deficient anemia (3) and as a screening test in suspected cases of hereditary hemochromatosis, a common genetic disorder that causes chronic iron overload and severe health problems if untreated (4)(5)(6).

Several approaches are used at present to determine TIBC. One common method involves a pretreatment step. An excess of iron is added to fully saturate all the serum iron-binding sites; any remaining free iron is then removed by a solid-phase absorbent, and the TIBC is determined by a serum iron test. Various methods are used to remove the excess iron, including the following: magnesium carbonate adsorption and centrifugation, which is the proposed reference method (7)(8); alumina minicolumns (9); ion-exchange resins (10); and magnetically responsive alumina-containing particles (11). All of these methods require a separation step and involve manual manipulation of the samples. Alternative approaches include use of the unbound iron-binding capacity (UIBC), in which a fixed amount of iron is added to a sample at a neutral pH and the uptake of iron by the unoccupied serum iron-binding sites is measured by a serum iron method as a decrease in free iron. The TIBC is then calculated as the sum of the serum iron plus the UIBC. Although this approach can be automated, it requires two separate analyses: serum iron and serum UIBC. Existing UIBC methods generally exhibit a significant negative bias compared with TIBC methods [Ref. (12) and confirmed in this study]. This bias is also evident in proficiency surveys in which the calculated TIBC has a 7–10% negative bias relative to the proposed magnesium carbonate reference method. Although the reason for this negative bias has not been fully investigated, the use of an aqueous saturating/calibration solution with an assigned value rather than a serum-based calibrator is one possibility (12).

Another widely used method involves determination of the transferrin concentration by immunoassay, followed by a calculated conversion to TIBC (13). Recently, a method for the direct analysis of TIBC has been described in which a saturating amount of iron is added to the sample and any remaining excess iron is then reduced and reacted with ferrozine. This signal is removed by blanking the instrument. The pH is lowered, releasing iron from serum binding sites. This free iron is reduced and then measured colorimetrically as the TIBC. This approach requires three reagents (14)(15). We have developed an alternative direct method (patent pending) for the determination of serum TIBC that is suitable for automated analyzers and has several advantages over these existing methods.


   Materials and Methods
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 Abstract
 Introduction
 Materials and Methods
Results
 Discussion
 References
 
direct tibc assay principle
The Direct TIBC is a two-step assay. In the first step, the serum sample is added to reagent 1 (R1). R1 contains iron as ferric ion in sufficient quantity to saturate the highest anticipated TIBC in a complex with an excess of Chromazurol B in acetate buffer at pH 4.5. When the serum sample is added, the serum iron is released from transferrin because of the low pH. The iron from the sample then forms a complex with the remaining excess of Chromazurol B, increasing the absorbance. The resulting absorbance signal at the end of the first step is attributable to both the serum iron and the saturating amount of iron already present in R1. In the second step, reagent 2 (R2), which is strongly buffered and contains bicarbonate ions, is added. The affinity of transferrin for iron increases dramatically, and the transferrin extracts the iron from the iron-dye complex, decreasing the absorbance. The decrease in absorbance is directly proportional to the TIBC.

direct tibc reagent
The Direct TIBC reagent set consists of Reagent 1 (R1), which contains 166 µmol/L Chromazurol B (Dojindo Molecular Technologies), 735 µmol/L cetrimide (Sigma Chemical Co.), 4.1 mmol/L thiourea (Sigma), and 16 µmol/L ferric chloride hexahydrate (Aldrich Chemical Co.) in acetate buffer, pH 4.55. Reagent 2 (R2) contains 338 mmol/L sodium bicarbonate (Sigma ) in MOPS buffer, pH 7.3. The assay uses a serum-based calibrator with an assigned TIBC value. Direct TIBC assays were run on a COBAS FARA II and the Olympus AU400.

direct tibc cobas fara method
The following instrument settings were used for the Direct TIBC assay on the COBAS FARA: wavelength, 660 nm; temperature, 37 °C; instrument set for endpoint mode. The analyzer added 16 µL of sample to 200 µL of R1 and incubated the mixture for 5 min. The instrument then added 60 µL of R2 and immediately measured the absorbance for use as the blank. The mixture was then incubated for 7 min, and the final absorbance measurement was taken.

direct tibc olympus au400 method
The following instrument settings were used for Direct TIBC assay on the Olympus AU400: wavelength, 660 nm; temperature, 37 °C; instrument set for endpoint mode. The analyzer added 16 µL of sample to 200 µL of R1 and then incubated the mixture for 10 cycles. The instrument then added 60 µL of R2 and immediately measured the absorbance for the blank. The mixture was incubated for 17 cycles, and the final absorbance measurement was taken.

magnetic tibc method
Magnetic TIBC reagent sets were from Equal Diagnostics, Inc. For studies using the COBAS instruments, supernates from the magnetic particle-treated samples were analyzed on a COBAS MIRA analyzer (Roche Diagnostics) with serum iron reagents from Thermo-DMA, Inc. For studies using the Olympus AU400, serum iron reagents from Olympus America, Inc. were used.

alumina column method
Alumina columns and saturating solution were obtained as a reagent set (J&S Medical Associates, Inc). Column-treated samples were analyzed on a COBAS MIRA analyzer with Thermo-DMA serum iron reagents.

calculated tibc by uibc and serum iron method
Serum iron and UIBC were determined on a COBAS MIRA with serum iron/UIBC reagents from Thermo-DMA. The TIBC was then calculated as the sum of the UIBC and serum iron.

correlation studies
A total of 125 serum samples with TIBC values ranging from 17.0 to 99.2 µmol/L (95–554 µg/dL) were analyzed on the COBAS MIRA analyzer by all three TIBC methods, and the results were compared by linear regression analysis. In a separate study, the results of another set of 128 serum samples with TIBC method values ranging from 23.6 to 98.8 µmol/L (132–552 µg/dL) were analyzed by the Direct TIBC on an Olympus AU400 analyzer, and the results were compared with those obtained with the magnetic TIBC assay on the same analyzer.

precision studies
We assessed assay precision with two commercially available serum-based chemistry controls, Multiqual 1 and Multiqual 3 (Bio-Rad Laboratories), on both the COBAS FARA and Olympus AU400. Within-run precision was assessed by analysis of 25 replicates in one run. Between-run precision was assessed by analysis of 25 replicates in 25 separately calibrated runs during the course of these studies.

linearity study
We determined the linearity of the assay by adding additional human transferrin to a serum pool to make an increased-TIBC pool. This pool was then serially diluted with physiologic saline to create a set of linearity samples.

interference studies
We assessed the effects of lipemia (expressed as triglycerides), hemolysis, bilirubin, ascorbate, copper, chromium, nickel, zinc, iron dextran, ferrous sulfate, and deferoxamine by adding each potential interfering compound at various concentrations to serum pools and testing for the recovery of TIBC. We assessed the effect of the anticoagulants heparin, EDTA, and oxalate/sodium fluoride by collecting blood from three volunteers simultaneously into a serum tube and heparin, EDTA, and oxalate/sodium fluoride plasma tubes and comparing the recovery in the Direct TIBC assay between serum and the various plasma samples. Informed consent was obtained from the volunteers.

statistical analyses
Means, SDs, and CVs were calculated, and correlations were assessed by least-square regression analysis with Microsoft Excel software (Microsoft, Inc.) and a statistical macro-package, SPC KISS, Ver. 2.0 (Digital Computations, Inc.), which works as part of the Microsoft Excel program.


   Results
Top
 Abstract
 Introduction
 Materials and Methods
 Results
Discussion
 References
 
studies using the cobas fara ii
A plot of the absorbance vs time for a serum-based calibrator with an assigned value of 64.1 µmol/L (358 µg/dL) in the Direct TIBC assay on the COBAS FARA is shown in Fig. 1 . The observed absorbance change was 3.9 mA per µmol/L TIBC (0.76 mA per µg/dL TIBC). To assess the linearity of the Direct TIBC assay, we prepared a set of samples by serial diluting an increased serum TIBC pool and assaying the dilutions in the Direct TIBC assay. The assay was linear between 12.5 and 125 µmol/L (70–700 µg/dL). The Direct TIBC assay was highly correlated with both the magnetic TIBC and alumina column TIBC methods (see Fig. 2 ). Statistical analysis of the results yielded the following correlations: for magnetic TIBC vs Direct TIBC, r = 0.987 (P <0.001), Sy|x = 2.6 µmol/L, slope = 1.05, y-intercept = -1.0 µmol/L (-5.4 µg/dL); for TIBC by alumina column vs Direct TIBC, r = 0.982 (P <0.001), Sy|x = 3.0 µmol/L, slope = 1.07, intercept = -1.0 µmol/L (-5.8 µg/dL). The calculated TIBC and the Direct TIBC were also highly correlated (r = 0.982; P <0.001; Sy|x = 3.0 µmol/L), but with a proportional bias (slope = 1.14; SEslope = 0.2) and a y-intercept of 3.4 µmol/L (18.8 µg/dL; see Fig. 2 ). Analysis of a subset of these data by two other commercially available UIBC and serum iron methods yielded similar biases (data not shown). This bias is similar to that reported in other studies (12).



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  		Figure 1. Absorbance curve for a serum-based calibrator [assigned value, 64.1 µmol/L (358 µg/dL)] in the Direct TIBC assay.

Measured on the COBAS FARA II at 660 nm.



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  		Figure 2. Correlation of Direct TIBC with other TIBC methods.

(A), correlation of magnetic TIBC (x) and Direct TIBC (y). The equation for the line is: y = 1.05x - 1.0 µmol/L; r = 0.987. (B), correlation of the alumina column method and Direct TIBC. The equation for the line is: y = 1.07x - 1.0 µmol/L; r = 0.982. (C), correlation of calculated TIBC (serum iron + UIBC) and Direct TIBC. The equation for the line is: y = 1.14x + 3.4 µmol/L; r = 0.982. Direct TIBC assay was performed on the COBAS FARA II and magnetic TIBC, alumina column method, and calculated TIBC values were determined on the COBAS MIRA.

The precision of the Direct TIBC was assessed with two serum-based commercially available chemistry controls. The results are summarized in Table 1 , and both the within- and between-run imprecision (CV) for the COBAS FARA was <=3.8%. Comparison of plasma and serum samples demonstrated that plasma is not an acceptable sample for use in the Direct TIBC assay, most likely because of competitive chelation of iron by anticoagulants (see Table 2 ).


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  		Table 1. Precision studies.


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  		Table 2. Effects of anticoagulants on Direct TIBC assay.

We assessed the specificity of the assay for iron vs other transition metals by supplementing serum pools with concentrations of copper (0–471 µmol/L), zinc (0–38.3 µmol/L), nickel (0–85 nmol/L), and chromium (0–962 nmol/L) that exceeded the highest reported reference values for those metals; no interferences were noted. This confirms other published studies on the use of Chromazurol B in iron determinations (16). We examined the effect of lipemia by mixing a specimen with increased triglyceride and TIBC concentrations proportionally with a specimen with low triglyceride and TIBC concentrations. Triglyceride concentrations up to 14.9 mmol/L (1318 mg/dL) had no effect on recovery. Bilirubin up to 547.2 µmol/L (32 mg/dL) and hemoglobin up to 77.5 µmol/L (500 mg/dL) demonstrated no interference (Fig. 3 ), and ascorbate decreased Direct TIBC values only at high concentrations well above those attainable even with megadose oral administration of ascorbic acid (17). We examined the effects of iron supplements by adding them to serum pools (Table 3 ). Iron dextran had no effect on assay performance. Ferrous sulfate >72 µmol/L (400 µg/dL) iron added decreased measured TIBC. This result is to be expected because the TIBC is exceeded and the free iron exceeds the capacity of the dye. However, serum iron concentrations >72 µmol/L (400 µg/dL) would represent an acute overdose, not a therapeutic dose. The results suggest that the Direct TIBC assay, like other TIBC assays (18), would be of limited use in cases of acute overdose with iron. Added deferoxamine increased Direct TIBC values only at concentrations >44.6 µmol/L, well above therapeutic serum concentrations (19).



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  		Figure 3. Effect of increased bilirubin and hemoglobin concentrations on Direct TIBC assay.

Conventional units: bilirubin, 0–32 mg/dL; hemoglobin, 0–500 mg/dL.


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  		Table 3. Effect of iron supplements on results of the Direct TIBC assay.

studies using the olympus au400
The Direct TIBC assay was highly correlated with the magnetic TIBC when both assays were performed on the Olympus AU400 (see Fig. 4 ). Statistical analysis of the results yielded the following correlations: magnetic TIBC vs Direct TIBC, r = 0.983 (P <0.001; Sy|x = 3.0 µmol/L); slope = 0.997; y-intercept = 0.1 µmol/L (0.4 µg/dL). Within- and between-run imprecision (CV) were <=4.8%.



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  		Figure 4. Correlation of the Direct TIBC assay with magnetic TIBC on the Olympus AU400.

Equation for the line: y = 0.997x + 0.1; r = 0.983.


   Discussion
Top
 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
References
 
There is renewed interest in analyses measuring various aspects of iron metabolism. Recent studies have demonstrated that hereditary hemochromatosis is one of the most common genetic disorders (6), and the utility of screening the general population is being examined (5). Several approaches for screening the general population have been proposed. These include determining the percentage of transferrin saturation, which requires determination of serum TIBC or transferrin (4)(5), or alternatively, genetic testing for the C282Y and H63D mutations in the HFE gene (20)(21). Furthermore, TIBC is useful in the diagnosis of iron deficiency, which remains the most prevalent nutritional deficiency in the US (3). Present methods for determining serum TIBC have numerous drawbacks, including manual manipulation of the samples, separation steps, the requirement for more than one analysis, and the use of nonserum calibrators.

We have described a new, fully automated, Direct TIBC assay suitable for most chemistry analyzers. The method compares well with the existing alumina column and magnetic alumina particle TIBC methods, is specific for TIBC, and is unaffected by lipemia, bilirubinemia, hemolysis, and other potentially interfering compounds. Furthermore, the method is calibrated with a serum-based calibrator. In contrast to another recently reported direct TIBC method (14)(15), our method does not require a reduction step and requires only two reagents. We believe that this Direct TIBC method is suitable for routine use in clinical chemistry laboratories and will improve the quality of iron metabolism studies.


   References
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 Abstract
 Introduction
 Materials and Methods
 Results
 Discussion
 References
 

  1. Burtis CA Ashwood ER eds. Tietz textbook of clinical chemistry 3rd ed 1999:1698-1703 WB Saunders Philadelphia. .
  2. Huebers HA, Finch CA. The physiology of transferrin and transferrin receptors. Physiol Rev 1987;67:520-582.[Free Full Text]
  3. . Centers for Disease Control and Prevention. Recommendations to prevent and control iron deficiency in the United States. MMWR Morbid Mortal Wkly Rep 1998;47(no. RR-3):10-18.
  4. Lyon E, Frank E. Hereditary hemochromatosis since discovery of the HFE gene. Clin Chem 2001;47:1147-1156.[Abstract/Free Full Text]
  5. Powell L, George DK, McDonnell S, Kowdley K. Diagnosis of hemochromatosis. Ann Intern Med 1998;129:925-931.[Abstract/Free Full Text]
  6. Phatak P, Sham R, Raubertas R, Dunnigan K, O’Leary M, Braggins C, Cappuccio J. Prevalence of hereditary hemochromatosis in 16031 primary care patients. Ann Intern Med 1998;129:954-961.[Abstract/Free Full Text]
  7. National Committee for Clinical Laboratory Standards. Determination of serum iron and total iron binding capacity; proposed standard. NCCLS document H17-P, Vol. 10, No. 4. Wayne, PA: NCCLS, 1990..
  8. Ramsey W. The determination of the total iron-binding capacity of serum. Clin Chim Acta 1957;2:221-226.
  9. Starr R. Use of an alumina column in estimating total iron-binding capacity. Clin Chem 1980;26:156-158.[Abstract/Free Full Text]
  10. Henry RJ. Clinical chemistry, principles and technics, 1st ed 1964:391-395 Harper & Row New York. .
  11. Siek G, Lawlor J, Pelczar D, Sane R. Development and performance characteristics of a magnetic separation based TIBC [Abstract]. Clin Chem 1999;45:A167-A168.
  12. Gambino R, Desvarieux E, Orth M, Matan H, Ackattupathil T, Lijoi E, et al. The relationship between chemically measured total iron-binding capacity concentrations and immunologically measured transferrin concentrations in human serum. Clin Chem 1997;43:2408-2412.[Abstract/Free Full Text]
  13. Beily J, Olynyk J, Ching S, Prins A, Swanson N, Reed W, et al. Transferrin index: an alternative method for calculating the iron saturation of transferrin. Clin Chem 1992;38:2078-2081.[Abstract]
  14. Yamanshi H, Kimura S, Iyama S, Yamaguchi Y, Yanagihara T. Fully automated measurement of total iron-binding capacity in serum. Clin Chem 1997;43:2413-2417.[Abstract/Free Full Text]
  15. Yue Y, Arana C, Staples M. Development of a fully automated TIBC method for the Dimension® clinical chemistry system [Abstract]. Clin Chem 2000;46:A146.
  16. Tabacco A, Moda E, Tarli P, Neri P. An improved, highly sensitive method for the determination of serum iron using Chromazurol B. Clin Chim Acta 1981;114:287-290.[Web of Science][Medline] [Order article via Infotrieve]
  17. Levine M, Conry-Cantilena, Wang Y, Welch R, Washko P, Dhariwal K, et al. Vitamin C pharmacokinetics in healthy volunteers: evidence for a recommended dietary allowance. Proc Natl Acad Sci U S A 1996;93:3704-3709.[Abstract/Free Full Text]
  18. Thompson D. Reassessment of measuring total iron-binding capacity in acute iron overdose. Ann Pharmacother 1994;28:63-66.[Abstract]
  19. Desferal®. Novartis Pharmaceutical. Deferoxamine mesylate iron and aluminum chelating agent. http://www.rxmed.com (Accessed November 1998)..
  20. Barton J, Acton R. Population screening for hemochromatosis: has the time finally come?. Curr Gastroenterol Rev 2000;2:18-26.
  21. Powell L, Subramanin V, Yapp T. Haemochromatosis in the new millennium. J Hepatol 2000;32(Suppl 1):48-62.



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