Micro serial processing of continuous sample streams in microfluidic environments provides a new, powerful and scalable approach for micro scaled chemical reactions and analytical procedures. It is based on sample generation by embedding sample liquid in a continuous stream of an immiscible carrier fluid. Segmented streams are processed in capillaries with integrated microfluidic devices for chemical and analytical processing. Devices and methods were developed for generation of segmented flows and for dosing of liquid into compartments of a segmented sample stream. Segmentation is realized with predefined compartment volume and a high degree of uniformity in size and frequency. Injectors are optimized for interoperatibility with segmented flow handling in HPLC-capillary systems. For fabrication of microfluidic devices two half channels were prepared in glass by means of an isotropic etch process, followed by anodic bonding mediated by a nickel chromium metalization. Segmented streams are generated in the injector module and guided into a dosing module, where controlled infusion of liquid into the compartments of the segment stream is realized. The system was used for a neutralization reaction in compartments containing formic acid with sodium hydrogen phosphate.