This work presents a new design concept for the development of portable, autonomous and low cost analytical devices that require a sample preparation of large volumes of blood. Diverse microfluidic components, such as a microtrench for blood cells filtration and a lateral flow assay (LFA) for result detection, were assembled in a simple and modular way, leading to an autonomous Point-of-Care (POC) device in which liquid pumping and flow modulation was performed by a self-powered micro-pump (μPump). In the first place, a modular design of a self-powered polydimethylsiloxane (PDMS) μPump was proposed, which worked via previous degasification of the material and allowed generation of a wide range of flow rates depending on the number of μPump modules used. Afterwards, different configurations of on-chip sample preparation modules were proposed, which were adapted for a range of blood volumes, as well as for the pumped flow rates. The whole blood was driven though the device via the integrated PDMS μPumps, and elimination of blood cells from whole-blood samples (using volumes up to 400 μL) was carried out in the microtrench by sedimentation, leading to a satisfactory plasma extraction of up to 60 μL. Finally, a proof of concept of an integrated analysis system was analysed by integrating a detection module together with the filtration and pumping modules. Overall, successful outcomes were accomplished for the sample preparation unit, together with a satisfactory flow performance on the LFA test, and it was demonstrated that the integrated self-powered micro-pumps (μPumps) are a versatile tool for autonomous liquid pumping and flow modulation.