Researchers have synthesized a sensitive biosensor that can selectively detect specific microparticles, which are released into blood by activated platelets1. These microparticles can signal the onset of platelet activation, a cellular process that can lead to blood clots forming in the arteries. Such blood clots restrict or block the flow of blood to the brain or heart and hence may cause a stroke or heart attack. The biosensor’s ability to identify the microparticles is thus potentially useful for predicting the risk of a heart attack or stroke.
To assess the risks associated with the generation of the platelet-derived microparticles, the researchers fabricated a biosensor by coating a glassy carbon electrode with graphene oxide and antibodies (PAC1), which bind to specific proteins on the microparticle surfaces.
The researchers performed electrochemical measurements while exposing the biosensor to plasma containing platelet-derived microparticles and tiny vesicles from non-platelet sources such as red blood cells. They found that the biosensor selectively detected the microparticles. The impedance (the ratio of the resistance to the current) increased dramatically when the microparticles bound to the biosensor.
The impedance rose with increasing plasma concentrations of the microparticles. By exploiting this effect, the researchers were able to use the biosensor to detect the presence of platelet-derived microparticles in blood samples of patients suffering from acute myocardial infarction.
“This biosensor could be used by the patient or a care provider from a drop of blood,” says lead researcher Debabrata Dash.
The authors of this work are from: Department of Biochemistry and Department of Cardiology, Institute of Medical Sciences, Banaras Hindu University, Varanasi and Department of Biotechnology, Motilal Nehru National Institute of Technology, Allahabad, India. This work has been supported by the Tata Innovation Fellowship grant received from Department of Biotechnology, Govt. of India.
