The present invention provides a syringe for filtering a liquid comprising: a housing with a plunger slidable therein； an inlet for taking in liquid from a liquid source into the housing； an outlet for expelling liquid from the inside of the housing； a filter； and a rotatable valve member being rotatable between a first position and a second position； wherein rotation of the valve member to the first position permits liquid that is drawn through the inlet into the housing by pulling the plunger to bypass the filter, and rotation of the valve member to the second position forces liquid that is expelled from the inside of the housing by pushing the plunger to pass through the filter and out of the outlet.
