Abstract: Membranes comprising first and second surfaces, the first surface comprising a patterned surface comprising peaks and valleys, first region surfaces comprising peaks, and second region surfaces comprising valleys; a porous bulk between the surfaces, the bulk comprising first region bulks and second region bulks; the region bulks extending from their respective region surfaces, the first region bulks comprising a first set of pores having outer rims, and a second set of pores connecting the outer rims of the first set of pores, and a first polymer matrix supporting the first set of pores; the second region bulks comprising a third set of pores having outer rims, and a fourth set of pores connecting the outer rims of the third set of pores, and a second polymer matrix supporting the third set of pores; filters including the membranes, and methods of making and using the membranes, are disclosed.