Wireless, Handheld, Non-Invasive Device Detects Alzheimer's and Parkinson's Biomarkers

By HospiMedica International staff writers
Posted on 21 Nov 2023

Image: The biosensor consists of a chip with a highly sensitive transistor (Photo courtesy of UC San Diego)

The prevalence of neurodegenerative diseases like Alzheimer’s and Parkinson’s is increasing. Current diagnostic methods for these conditions typically involve invasive procedures such as spinal taps and MRI scans, which can be daunting for patients and pose challenges for those with mobility issues or limited access to medical facilities. In response to these challenges, researchers have developed a groundbreaking handheld device that non-invasively detects biomarkers associated with Alzheimer’s and Parkinson’s Diseases. Additionally, this device has the capability to wirelessly transmit its findings to a computer or smartphone.

Developed by an international team of researchers led by UC San Diego (La Jolla, CA, USA), the device utilizes an electrical detection system rather than a chemical one. This approach is both simpler and more accurate. The core component of the device is a highly sensitive transistor, known as a field effect transistor (FET), featuring a graphene layer that is just one atom thick. This graphene FET (GFET) incorporates three electrodes: the source and drain electrodes connected to a battery’s positive and negative poles to facilitate current flow, and a gate electrode that regulates this current. A unique DNA strand, acting as a probe, is attached to the gate electrode. This probe specifically binds to amyloid beta, tau, or synuclein proteins. The interaction between these amyloids and their corresponding DNA probe alters the current between the source and drain electrodes, and it is this change in current or voltage that signals the presence of specific biomarkers.

The device’s effectiveness was validated using brain-derived amyloid proteins from deceased Alzheimer’s and Parkinson’s patients. The biosensors accurately detected the disease-specific biomarkers, matching the precision of current advanced diagnostic methods. Remarkably, the device requires only minimal sample quantities and can accurately perform even in samples containing a variety of proteins. While detecting tau proteins presented more challenges, the device’s ability to analyze multiple biomarkers allows for a comprehensive and reliable diagnosis. Future plans include testing the device with blood plasma, cerebrospinal fluid, and eventually saliva and urine samples in hospitals and nursing homes. Following successful trials, the researchers aim to seek FDA approval within the next few months, with the ultimate goal of commercializing the device within a year.

“This portable diagnostic system would allow testing at-home and at point of care, like clinics and nursing homes, for neurodegenerative diseases globally,” said Ratnesh Lal, a bioengineering, mechanical engineering and materials science professor at the UC San Diego Jacobs School of Engineering.

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