A micro potentiometric immunosensor for hemoglobin-A1c level detection based on mixed SAMs wrapped nano-spheres array

Area of Science:

• Biosensors and Nanotechnology
• Analytical Chemistry
• Medical Diagnostics

Background:

• Accurate monitoring of Hemoglobin-A1c (HbA1c) is crucial for diabetes management.
• Existing methods for HbA1c detection can be complex or time-consuming.
• Development of sensitive and stable immunosensors is an active area of research.

Purpose of the Study:

• To develop and characterize a micro potentiometric immunosensor for HbA1c detection.
• To utilize a mixed self-assembled monolayers (SAMs) wrapped nano-spheres array for improved sensor performance.
• To evaluate the sensor's performance in detecting HbA1c and hemoglobin (Hb) in clinical samples.

Main Methods:

• Fabrication of a micro immunosensor using an ISFET integrated chip and MEMS electrodes array.
• Preparation of a nano-spheres array by wrapping nano-gold particles with mixed SAMs.
• Covalent immobilization of antibodies onto the functionalized sensor surface.
• Potentiometric detection of HbA1c and Hb concentrations.

Main Results:

• The immunosensor demonstrated uniform distribution of nano-gold particles without aggregation due to mixed SAMs.
• Linear responses were observed for HbA1c in the range of 50-170.5 ng/ml and for hemoglobin in the range of 166.7-570 ng/ml.
• The immunosensor showed low relative deviation when tested with whole blood samples from a hospital.

Conclusions:

• The developed micro potentiometric immunosensor offers a stable and sensitive platform for HbA1c detection.
• The mixed SAMs wrapped nano-spheres array enhances sensor performance and reduces noise susceptibility.
• This immunosensor presents a promising alternative tool for the clinical determination of HbA1c levels.