Biosensor Development for Alzheimer's Disease Biomarker Detection

Alzheimer’s disease is characterised by the accumulation of amyloid‐β peptides and tau proteins long before clinical symptoms emerge. Biosensors offer a route to rapid, sensitive and potentially point-of-care detection of these molecular signatures in bodily fluids such as blood, serum or cerebrospinal fluid. Over the past decade, advances in nanomaterials, surface chemistry and transduction modalities have yielded devices capable of detecting biomarkers at picomolar to femtomolar concentrations. Key strategies include electrochemical platforms that transduce binding events into measurable currents or impedances, optical formats that exploit fluorescence quenching or enhancement and label-free approaches based on changes in capacitance or refractive index. Integration of antibodies, aptamers or molecularly imprinted polymers onto electrodes or sensor surfaces enhances selectivity, while the incorporation of metallic nanoparticles, carbon nanostructures and two-dimensional nanosheets amplifies signal sensitivity. Collectively, these developments promise earlier diagnosis, improved patient stratification and monitoring of therapeutic efficacy, with the long-term goal of translating lab-scale prototypes into robust clinical tools.

Research from Nature Portfolio

A densely aligned carbon nanotube sensor array has been developed for simultaneous, ultrasensitive measurement of total tau, phosphorylated tau181, Aβ42 and Aβ40 in human plasma. The unidirectional arrangement of nanotubes ensures uniform electronic pathways, yielding femtomolar limits of detection and coefficients of variation below 6%. By analysing biomarker ratios such as p-tau181/Aβ42, the device discriminates Alzheimer’s patients from healthy controls with approximately 90% sensitivity and specificity. This multiplex approach demonstrates the feasibility of blood-based assays to rival cerebrospinal fluid diagnostics, moving a step closer to minimally invasive clinical screening.

Biosensor Development for Alzheimer's Disease Biomarker Detection publication trend

The graph below shows the total number of articles in biosensor development for alzheimer's disease biomarker detection across all publications each year (not limited to Nature Index journals).

Technical terms

Biomarker: A measurable indicator of a biological state, here referring to proteins such as amyloid-β and tau linked to Alzheimer’s disease.

Electrochemical biosensor: A device that converts a biochemical interaction into an electrical signal, commonly using electrodes modified with recognition elements.

Electrochemiluminescence (ECL): Light emission triggered by electrochemical reactions, used to quantify targets bound to an electrode surface.

Aptamer: A short nucleic acid sequence selected to bind specifically to a molecular target, used as a recognition element in biosensors.

Surface plasmon resonance (SPR): A label-free optical technique that detects changes in refractive index near a metal surface upon biomolecule binding.

Limit of detection (LOD): The lowest concentration of an analyte that can be reliably distinguished from background noise by a given sensor.

Nanomaterial: A material with structural features at the nanoscale (1–100 nm) that imparts unique electrical, optical or catalytic properties for signal amplification.

References

1. Functional Nanomaterials for the Diagnosis of Alzheimer's Disease: Recent Progress and Future Perspectives. Advanced Functional Materials (2023).
2. Clinically accurate diagnosis of Alzheimer’s disease via multiplexed sensing of core biomarkers in human plasma. Nature Communications (2020).
3. An Electrochemiluminescence Biosensor for the Detection of Alzheimer’s Tau Protein Based on Gold Nanostar Decorated Carbon Nitride Nanosheets. Molecules (2022).
4. A Probeless Capacitive Biosensor for Direct Detection of Amyloid Beta 1-42 in Human Serum Based on an Interdigitated Chain-Shaped Electrode. Micromachines (2020).