The present invention relates to an arrangement for collection and separation of a body fluid, e.g. whole blood, for purposes of analysis of a component, e.g. plasma, of a sample of the body fluid. It comprises means for receiving a body fluid, a filter arrangement (50) comprising a separation filter arrangement for separation of the component(s) to be analysed and a detection filter in communication with the separation filter arrangement. The filter arrangement comprises a pre-filter (6) having a filter volume adapted to be capable to receive a volume of body fluid exceeding a volume of a sample to be analysed, which comprises a first portion defining a sample zone volume arranged to form a sample zone and at least one second portion defining an excess removal zone volume, forming an excess fluid removal zone the volume of which exceeds said sample zone volume. The separation arrangement defines a separation zone volume, and flow control means (11A,11A,11B) are provided to control the transportation or flow of body fluid to the separation arrangement forming the separation zone and to the excess fluid removal zone.
