Abstract: A method of forming electrospun fiber mats from a plurality of different biodegradable polymeric fibers is provided, in which a plurality of up to six different biodegradable polymer solutions are electrospun together by a method comprising the steps of providing a plurality of up to six different biodegradable polymer solutions each containing at least one biologically or pharmaceutically active material and each in communication with a needle for electrospinning a biodegradable polymer fiber from the solution, and pumping each solution through its respective needle into an electric field under conditions effective to produce uncontrolled charged jet streams of the polymer solutions directed at a grounded rotating mandrel, thereby forming fiber threads of the biologically or pharmaceutically active compounds and polymers in the solutions that are deposited on the mandrel to form an electrospun non-woven fiber mat, wherein the needles are positioned for co-deposition of the fiber threads from the polymer solu