Measurement of HbA1c with a new phase function using RBC phase image from a low-cost digital holographic microscopy

Development of a new phase function for measuring HbA1c, using a low-cost digital holographic microscopy to monitor the glucose level in diabetes.

Here, we propose a new parameter, ${\text{Ø}}_{\mathrm{cp}}$ based on two different phases of RBCs, one, the absolute phase at the center, ${\text{Ø}}_c$ and the other, the average phase at the periphery, ${\text{Ø}}_p$ . The ${\text{Ø}}_{\mathrm{cp}}$ value varied almost linearly (R² = 0.952) with HbA1c (%) in the blood. We used a low-cost digital holographic microscope (DHM) to record the hologram of RBCs, followed by digital reconstruction with the help of our newly introduced code. The critical value of ${\text{Ø}}_{\mathrm{cp}}$ at 3.5 was found to be equivalent to 6.5% HbA1c in high-performance liquid chromatography (HPLC), beyond which indicates hyperglycemia.

The method can be used for large-scale and low-cost estimation of HbA1c (%) with ${\text{Ø}}_{\mathrm{cp}}$ of ≥ 3.5.