Cheap, portable biosensor to improve Alzheimer's management

Scientists, including one of Indian-origin, have developed a simple, sensitive and portable biosensor to monitor the progress of Alzheimer's disease, which would greatly improve the patient's quality of life.
Researchers from Florida International University in the US are taking a new approach to diagnosing Alzheimer's by measuring the amount of a peptide called beta-amyloid in the blood with the cheap, quick, accurate point-of-care test.
They hope their new approach will help patients, including those in developing countries, benefit from personalised treatment for Alzheimer's disease.
Alzheimer's disease is caused by high levels of beta-amyloid in the brain, which leads to the degeneration of brain cells, researchers said.

Currently there is no sensitive or inexpensive way to measure beta-amyloid levels in the blood, they said.
"We want to develop a point of care system, where a small drop of blood plasma can reveal their beta-amyloid level immediately so that a doctor can tailor a patient's therapy," said Ajeet Kaushik from University of Florida.

"The drugs used to treat Alzheimer's disease can have side effects, so it is better for patients not to overdose. With the right data, doctors can respond quickly to changes in a patient's brain by reducing or increasing their dose," said Kaushik.
Researchers looked at each of the methods available to measure beta-amyloid concentration in brain tissue and in blood. None of the existing tests can be done at the bedside and all need special expertise and large samples.

They also take a long time to generate a useful result - the main existing test, called ELISA, takes six to eight hours.
In comparison, the cheap, simple biosensor researchers describe can measure beta-amyloid in the blood at tiny concentrations in just half an hour.
"Even though existing technologies are well established, we need to move towards small sample, high accuracy tests that can be used in all environments, from developed countries to rural settings. Our goal is to develop a test that's sensitive, small and affordable," said Kaushik.
"A quick biosensor test will enable a clinician to collect information on the progression of disease and see what is happening to a patient over time. It will also show if and when the disease reaches an untreatable level," he added.

The findings were published in the journal Biosensors and Bioelectronics.