Method for quantifying free hemoglobin, distinct from the hemoglobin-haptoglobin complex, in human serum

Area of Science:

• Clinical Chemistry
• Immunology
• Hematology

Background:

• Accurate measurement of free hemoglobin (free Hb) is vital for diagnosing and managing hemolytic diseases and preventing organ damage.
• Current colorimetric methods lack specificity, measuring total hemoglobin (Hb) instead of free Hb.
• Size-exclusion high-performance liquid chromatography (SEC-HPLC) offers specificity but is time-consuming for clinical use.

Purpose of the Study:

• To develop a rapid and specific assay for quantifying free Hb in serum.
• To differentiate free Hb from the hemoglobin-haptoglobin complex (Hb-Hp).
• To provide a clinically applicable method for monitoring free Hb levels in patients with hemolytic conditions.

Main Methods:

• Development of a novel latex agglutination immunoturbidimetric assay (LATIA).
• Assay validation using Hb-spiked serum samples from healthy adults.
• Comparison of LATIA results with SEC-HPLC for specificity and correlation.

Main Results:

• The LATIA method accurately quantifies free Hb in serum within the 1-100 μg/mL range.
• The assay provides results in approximately 15 minutes using an automated biochemistry analyzer.
• High correlation was observed between LATIA and SEC-HPLC, confirming high specificity for free Hb.

Conclusions:

• The novel LATIA assay offers a rapid, specific, and potentially clinically useful method for free Hb measurement.
• This assay can aid in monitoring disease progression and guiding therapeutic strategies in hemolytic diseases.
• Further clinical studies are necessary to fully evaluate the performance and impact of this new assay.