A filter media structure, which is capable of operating in the micro- and nanofiltration regime, offers: low cost, durability, high temperature and chemical resistance, high permeability, high flow rate, low pressure drop across the filter media, high mechanical strength, separation efficiency, and biocompatibility. The filter media structure is comprised of blend of carbon or ceramic fibers and inorganic fiber whiskers generally having a diameter of from about 0.03 to about 5 microns. In one embodiment, filter media structure is comprised of blend of activated carbon-containing inorganic fibers and inorganic fiber whiskers generally having a diameter of from about 0.03 to about 5 microns.