Nonwoven, biodegradable membranes fabricated by electrospinning have recently attracted a great deal of attention for biomedical applications. In this study, microporous, nonwoven membranes Of poly(L-lactide) and its copolymers and blends were fabricated through electrospinning. The structures and morphologies of the electrospun membranes were investigated with scanning electron microscopy, differential scanning calorimetry, and X-ray diffraction. Different polymer membranes, incorporated with carmofur, were fabricated, and their drug release profiles were investigated. Scanning electron microscopy images showed that the fiber diameters were down to the nanometer range. The diameters and morphologies of the nanofibers depended on processing parameters such as the solution properties (concentration and polymer molecular weight), applied electric voltage, solution feeding rate, and needle diameter. Differential scanning calorimetry showed that the crystallinity of the electrospun membranes was lower than that of the cast film. For all the membranes incorporated with the drug, there was a burst release in the first 10 h of incubation in phosphate-buffered saline at 37 degrees C. Poly(glycolide-co-lactide) membranes showed faster and more complete drug release than poly(L-lactide), and this could be attributed to its faster degradation. The incorporation of polylactide-poly(ethylene glycol) could shorten the drug release time. A combination of suitable degradable biomaterials with an appropriate electrospinning process could be useful in the fabrication of a new kind of membrane suitable for different biomedical applications such as tissue engineering and drug delivery. (C) 2008 Wiley Periodicals, Inc.