Abstract: The invention relates to a device (1) for analyzing biological samples (S) comprising a substrate (2) for receiving a biological sample (S), wherein the substrate (2) comprises or consists of a fibrous material (F) configured to form a stationary phase which retains molecules in a biological sample (S) dissolved in a liquid mobile phase depending on molecular weight and/or polarity of the molecules, a first electrode (41) and a second electrode (42), which are arranged along a first axis (A1) and configured to generate an electric field acting along the first axis (A1) when an electric potential difference is provided between the first electrode (41) and the second electrode (42), so that charged molecules contained in the biological sample (S) are movable through the substrate (2) along the first axis (A1) and/or separable by their molecular weight, their polarity and/or their charge, wherein the substrate (2) comprises a chemical lysing agent (L) capable of lysing the biological sample (S).