Mechanical detection of liposomes using piezoresistive cantilever

This paper firstly reports the mechanical and real-time detection of liposomes using the highly sensitive microfabricated piezoresistive cantilever sensor chip and liposome-protein interaction. The cantilevers were functionalized with the chemically modified protein C2A which recognizes the phosphatidylserine (PS) exposed on the surface of liposome. The attachment of liposome induced the bending motion of the piezoresistive cantilever and consequently generated the electrical signal changes. The sensitivity of the sensor was determined from the relationship between electrical signal and the number of liposome immobilized on the cantilever surface. This result will help challenge a new detection method to monitor various micro-sized organisms such as bacteria and animal cells.