Microfluidics is the study of small-scale transport phenomena and has great potential in the field of biomedical research. Lab-on-chip technology comprises microfluidic networks that allow for integration of numerous bioanalytical processes, offering many advantages over conventional systems. This thesis details research projects in three different areas of microfluidics. The first section describes the development and experimental validation of a miniaturized real time PCR (polymerase chain reaction) system, including DNA quantification results for Escherichia coli. The second section describes the design of an embedded microheater for poly(dimethylsiloxane) or PDMS microchannel systems. The thermal field generated by the microheater was measured using temperature dependent dye. The third section describes a novel method of flow velocity measurement in microchannels, by applying a heat pulse to temperature dependent dye flowing in a capillary. The heat pulse was tracked by monitoring fluorescent intensity, and the average flow velocity was determined from the heat pulse velocity.