Different optofluidic devices and their biochemical applications in inhomogeneous media are discussed. In optofluidic chips, various new technologies, such as the optofluidic waveguides, the lenses, the cell counting and the chemical detection, are developed and implemented from two aspects. Firstly, in the liquid-liquid inhomogeneous medium, the gradient and step refractive index distributions of the liquid in the micro cavity are realized by adjusting the flow rates in the channel and controlling the convection-diffusion between the liquids to achieve the special optical properties, such as the beam separation, the bending, and the self-focusing. Secondly, in the solidliquid inhomogeneous medium, a series of adjustable and more sensitive detections are achieved by combining the special microfluidic structure with the liquids. These new technologies play a key role in many biochemical applications, for example, the biosensing, the energy production and the seawater detection. Thus, with the development of the optofluidics, the tunable devices in inhomogeneous media will have great potential biomedical applications.

optofluidic  /  inhomogeneous media  /  gradient refractive index  /  step refractive index