Hemoglobin quantification in red blood cells via dry mass mapping based on UV absorption

Area of Science:

• Biomedical Optics
• Cellular Imaging
• Hematology

Background:

• Red blood cell (RBC) morphology and hemoglobin (Hb) content are crucial for diagnosing hematological disorders.
• Label-free mass mapping, particularly deep ultraviolet (UV) microscopy, offers precise Hb quantification in individual cells, presenting an alternative to conventional analyzers.

Purpose of the Study:

• To compare UV absorption-based mass mapping across four UV wavelengths.
• To assess variations in Hb quantification accuracy based on wavelength.
• To identify necessary assumptions for accurate Hb mass determination.

Main Methods:

• Whole blood smears were imaged using a multispectral UV microscopy system.
• RBC dry masses were computed and compared to quantitative phase imaging (QPI) mass mapping.
• UV absorption-based mass mapping was performed at 220, 260, 280, and 300 nm.

Main Results:

• Consistent Hb mass and mean corpuscular Hb values were achieved across all tested UV wavelengths.
• Single-cell mass measurement precision was nearly identical at 220, 260, and 280 nm, with a slight decrease at 300 nm.

Conclusions:

• UV absorption-based mass mapping provides reliable Hb quantification for RBCs.
• A single UV wavelength is sufficient for comprehensive hematological analysis, including Hb quantification and white blood cell characterization.
• This technique enhances the speed and cost-effectiveness of hematological analysis.