last 10–15 years, and new developments in centrifugal microfluidic technologies have the potential to establish widespread utilization of the platform. Therefore, different liquid-handling platforms have been developed to implement unit operations such as sample take-up, sample preconditioning, reagent supply, metering, aliquoting, valving, routing, mixing, incubation, washing, as well as analytical or preparative separations. The integration of such sample preparation, incubation, analysis on a self-contained disc in a device that controls the spinning for automatic performance encourages the sample-to-answer diagnosis in the point-of-care biomedical platform. Dr. Marc Madou in UC Irvine is one of the leaders in the centrifugal micro-fluidic biochip. He has done several research projects on this area and has made great success such as pneumatic pumping in centrifugal microfluidic platforms, integration of 3D carbon-electrode dielectrophoresis, and serial siphon valving. His group members are working on projects including cell lysis, PCR card, DNA hybridization, anthrax diagnostics and respiratory virus detection (see external links). Dr. Hua-Zhong Yu in SFU.ca also made great progress in this area, proposing a new digitized molecular diagnostics reading method and a new DNA detection method on plastic CD. (see external links) Dr. Gang Logan Liu in UIUC is currently also focusing on this area (see external links). Structure design The design of structure bases on the principle of microfluidics and typical components are used in the platform. many structures for centrifugal microfluidic biochips have been developed, with more interesting ones yet to be released. Madou's group invented the valve-chamber structure in 2004. In recent years, Saki Kondo released the vertical liquid transportation structure, which pushed the design to become a three-dimensional concept. Madou's group also invented a serial siphon valving structure which makes flow control much easier. Hong Chen created a spiral microchannel which allows parallel testing with more steps. Principle The principle for the centrifugal micro-fluidic biochip includes the basic forces of a particle as well as the principle of flow control. For a particle in the flow the basic forces are centrifugal force, Coriolis force, Euler force and viscous force. The centrifugal force plays a role as a pump in the fluid flowing. It offers the basic source to transfer the fluid flowing from the inner radius of CD to the outer radius. The magnitude of the centrifugal force is determined by the radius of particle location and the rotational speed. The formula for centrifugal force density is: where N is the mass