Biosensors Can Help Detect The Impact Of Mild Traumatic Brain Injury

Posted on March 18, 2022

Biosensors that include an extraordinary combination of features to detect biomarkers related to TBI have been successfully developed. These tiny chips are flexible and thinner than human hair, making them ideal for use in the brain as they are minimally invasive.

Scientists can detect changes in concentrations of different chemicals in the body and send results in real-time to researchers. Dr. Jinghua Li, an assistant professor at Ohio State University, studied how the biosensors can be used to monitor patients with TBI.

TBI is the leading cause of disability, and diagnosis of TBI is mainly based on the patient’s history, finding son neurological examination, neuroimaging tools, and clinical assessment scales. Mild TBI patients often develop non-specific symptoms that include headaches, fatigue, depression, seizures, and visual and al or sleep disturbances. These symptoms may occur immediately following the injury or days or weeks later.

Secondary damage can occur after a brain injury, which is identified by changes in potassium and sodium ion concentrations in the brain’s CSF. A biosensor that can continuously monitor brain tissue to detect changes in ion concentrations in CSF can act as an early sign of the condition worsening. 

Apart from analyzing levels of ions and neurotransmitters, Dr. Li believes that biosensors can be used to analyze proteins, peptides, nucleic acids, and other chemicals in the body. This can bring a breakthrough in treating chronic diseases such as Alzheimer’s and Parkinson’s. 

Biosensors can play a crucial role in tracking long-lasting health conditions and early intervention and treatment of diseases. The chip contains electronic components that emit an electrical signal that can be detected and analyzed outside the body upon sensing the chemical of interest. 

The biosensor was tested in an artificial solution that mimicked CSF. The study found that the biosensor could accurately find changes in ion levels and identify changes in pH levels in human serum. 

Researchers have developed calibration standards to ensure that the device only responds to the specific chemicals and ignores crosstalk from other biomarkers. This cannot be easy in a complex system like our body. 

Moreover, the electronics in the chip must be protected from the fluids in the brain. Hence these sensors are encapsulated in a waterproof thin film of silicon dioxide to maintain structural integrity. This material was tested in various ways, placed in substances with different pH levels and heated fluids. 

Waterproof encapsulation of biosensors with several hundreds of nanometers of thickness can last a few years at body temperature or even longer. 

Diagnosis of mTBI is quite challenging as it is typically not associated with any structural changes on brain MRI and is difficult to be assessed by a standard diagnostic workup. Furthermore, MRI and CT scans are costly, cannot be available on-site, and can be dangerous to perform in patients with pacemakers and cochlear implants as exposure to ionizing radiation and strong magnetic fields can be harmful. Hence an increasing need to develop an inexpensive and accurate diagnostic tool for identifying and prognoses of mTBI. Biosensors can detect changes in biomarkers in CSF, serum, and plasma.