A facile, ultrasensitive, reproductive and selective sensor strip utilizing electrospun polyamide-6/nitrocellulose (PA-6/NC) nano-fibers/nets (NFN) membranes assemble bovine serum albumin decorated Au nanoparticles (BAu probe) for naked-eye colorimetric assay of Pb2+ has successfully prepared through dual-component alternate distribution multifluidic electrospinning technique. Benefiting from the extremely large specific surface areas and high porosity of NFN membranes, the stability of BAu probe dramatically increased and the strips presented a significant absorbance decreasing band at 546 nm which induce the visual color changes from deep pink to white after incubated in Pb2+ liquor with a low detection limit of 0.2 mu M without any assistance of equipment. Upon exposure to a series of metal ions, only Pb2+ could induce a pink-to-white color change, which clearly exhibited that BAu probe immobilized PA-6/NC membranes could act as highly selective strips to detect Pb2+ with little interference from other metal ions. Additionally, the colorimetric responses are represented in visualized quantitative by calculated color difference from L*a*b* coordinates which are presented with lightness and chrome values. Furthermore, the sensitivity of NFN membrane-based strips is much higher than that of film-based ones. The results indicate that this promising cost-effective sensing system could potentially allow for assaying of Pb2+ in human urine or blood as preliminary screening of lead poisoning. (C) 2013 Elsevier B.V. All rights reserved.