New Alzheimer test set to cut costsLocal | Phoenix Un 5 Jan 2018
Chemistry students at Hong Kong Baptist University have developed a new method to detect Alzheimer's disease simply by testing a patient's saliva or urine in just half an hour at HK$10 per time.
The team hopes this new method will become universal enough so the disease can be detected early for speedy treatment.
Alzheimer's disease, characterized by gradual loss of memory and cognitive and functional impairment, is one of the most common neurodegenerative disorders.
One in 10 Hong Kong elderly aged 70 or above has the disease, and the number increases to one in three among those aged 85 or above.
The research team, jointly led by Baptist professor Ricky Wong Man-shing and associate professor Li Hung-wing, introduced the new method to the public yesterday.
They invented a new type of cyanine compound to test whether a type of Alzheimer's disease-related protein, beta amyloid peptide, is present in the patient's body fluid.
The method will allow a low-cost and ultrasensitive detection by only testing a drop of human fluid, instead of health-risking invasive procedures such as magnetic resonance imaging, which requires injection, or lumbar puncture, which requires a needle to be injected into the spinal canal to collect fluid.
Their discovery has been granted four US patents and one patent by the Chinese government.
Li said cyanine was commonly present in nature such as in blueberries, and the cyanine compounds the team introduced were particularly suitable for detecting amyloid.
The detection started by placing the cyanine compound onto the surface of magnetic nanoparticles, then the patient's body fluid will be added onto it.
If the target amyloid is present in the body fluid, it will interact with the nanoparticle and cyanine compounds, and the reaction will emit fluorescent light which can be detected by ultraviolet imaging system.
This newly developed project will be particularly useful as a low-cost yet accurate diagnostic and prognostic tool for Alzheimer's disease, Li said, as it costs only HK$6 to HK$27 each time, much lower than the lumbar puncture costing HK$3,000 minimum.
It also took only half an hour for results, almost 16 hours shorter than lumbar puncture, she said.
"It can also serve as a novel alternative non-invasive tool for population-wide screening for the disease," she said.
Although the team succeeded in detecting amyloid in serum, saliva and urine, Li said the amount of amyloid in the three fluids is lower and would make the detection more difficult.
In another study, the team is also testing the use of cyanine compounds to detect a more toxic form of beta amyloid and treating Alzheimer's disease by stopping the aggregation of amyloid.