Microfluidic PMMA-based microarray sensor chip with imaging analysis for ABO and RhD blood group typing

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Materials Science

Background:

• Solid phase microarrays are used for blood typing, detecting red blood cells (RBCs) via surface plasmon resonance or fluorescence.
• Previous methods involved immobilizing antibodies to capture RBCs for detection.

Purpose of the Study:

• To develop and evaluate an antibody microarray on a Poly(methylmethacrylate) (PMMA) surface integrated with a microfluidic system for ABO and RhD blood typing.
• To utilize image recognition for detecting immobilized RBCs after antigen-antibody interaction.

Main Methods:

• Photochemical modification of PMMA surface followed by grafting with aminopropyltriethoxysilane (APTES) and glutaraldehyde cross-linking.
• Immobilization of monoclonal antibodies (anti-A, anti-B, anti-D) onto the modified surface via imine linkage.
• Detection of RBCs captured by immobilized antibodies using microarray image cell counting.

Main Results:

• Optimal conditions for RBC detection were identified as 10% RBC concentration and a 10 μl/min flow rate.
• Accurate blood group identification was achieved for all 136 samples tested, with minimal non-specific binding.
• The platform demonstrated good reproducibility with coefficients of variation of 2.17% (anti-A), 3.62% (anti-B), and 2.51% (anti-D).

Conclusions:

• The PMMA-based microarray chip offers high accuracy and precision for rapid blood group testing.
• The high-throughput nature of this method makes it suitable for large-scale applications, such as in blood donation centers.