Various aspects of the present invention pertain to porous membranes that comprise: (1) a plurality of pores with pore sizes of more than about 0.1 μm in diameter; and (2) a plurality of hydrophilic molecules. Additional aspects of the present invention pertain to methods of separating organic compounds from a liquid sample by: (1) providing the porous membrane; and (2) flowing the liquid sample through the porous membrane in order to retain organic compounds on the porous membrane. Further aspects of the present invention pertain to systems for separating organic compounds from a liquid sample. Such systems comprises: (1) the porous membrane; and (2) a flowing unit that enables the liquid sample to flow through the porous membrane. Additional aspects of the present invention pertain to methods of making the above-described porous membranes by: (1) coating a surface of a porous membrane containing 0.1 μm pores with a ceramic material; and (2) associating the coated surface of the porous membrane with hydrophilic molecules.