AFM: A biosensor has been developed for an accurate blood test for Alzheimer’s disease.
elchi reports that South Korean scientists have developed a new type of biosensor capable of detecting proteins associated with Alzheimer’s disease even in complex biological environments such as blood and plasma. The results of the study were published in the journal Advanced Functional Materials (AFM).
The device addresses a major problem in modern diagnostic technologies – the Debye screening effect, which previously significantly limited measurement accuracy.
The Debye screening effect occurs when a “cloud” of ions forms around charged particles in a solution, preventing biosensors from accurately detecting electrical signals from target molecules. This effect is particularly pronounced in physiological fluids due to high salt concentrations, which reduces the range of electrical interactions and impairs diagnostic sensitivity. To solve this problem, the researchers used insulated-gate transistor (IGT) biosensors that combine indium gallium oxide semiconductors with nanogrooves. This structure allows for the control of the local ionic environment at the semiconductor-electrolyte interface, reducing screening effects and ensuring more accurate detection of biomolecules.
Scientists used the tau protein, a key biomarker for Alzheimer’s disease, as a test system. The new sensor demonstrated high sensitivity and stability in detecting the protein across a wide concentration range and maintained functionality even in conditions similar to real biological fluids.
According to the authors, the technology could lay the foundation for the creation of more accurate and affordable next-generation diagnostic systems, including rapid tests for the early detection of neurodegenerative diseases.
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