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This thesis describes five new multiphase applications on the centrifugal microfluidic platform. A modular micromixer, based on the continuous flow through rotating microchannels on a standard laboratory centrifuge, is presented and applied to high-throughput reactive micromixing applications. Microfluidic emulsification enables the production of monodisperse droplet emulsions and is implemented on the centrifugal microfluidic platform within this thesis for the first time. The generation of monodisperse water droplets into a continuous oilflow within a flow-focusing microchannel structure is demonstrated. The encapsulation of living cells into biopolymer micro-beads constitutes an important multiphase process for therapeutic applications, e.g. for the implantation of insulin-producing cells in diabetes care. The encapsulation into alginate micro-beads protects the alien cells from the host immune system. A novel method for the direct, centrifugally induced fabrication of small alginate beads from rotating polymer-tube micronozzles is demonstrated. An innovative gas micropump is presented for the generation of gas-liquid flows on the centrifugal microfluidic platform. The injection of gas bubbles into liquid flows allows air-to-liquid sampling for e.g. centrifuge-based assays. Finally, a microfluidic integrated DNA extraction method, based on a simple frequency and dispensing protocol of a microfluidic rotor is presented. Compared to commercially available spin-columns, it allows an automated extraction of DNA. The key enabling step is the centrifugally induced generation of droplets which are routed by the Coriolis force either to a waste or to an eluate reservoir.