Molecular imprint enhanced specific adsorption visualization on electrospun chromogenic membrane for efficient detection of putrescine

Abstract

Electrospinning is an important tool for generating continuous fibers with large surface area and high pore ratio. The combination of nanofiber membrane and molecular imprinting can effectively measure specific adsorption of putrescine with coloring procedure. In this work, molecularly imprinted electrospun chromogenic membrane was synthesized with 1,4-butanediol (BDO) as imitate template. Poly(vinyl alcohol) (PVA) is used as spinning solution and ninhydrin as chromogenic agent for visualizing detection of target molecular putrescine. The adsorption concentration on molecularly imprinted polymer is illustrated by blue-purple colored stains and recorded by interactive three-dimensional surface plot of ImageJ. The results indicated that a uniform and bead-free PVA nanofiber was obtained using 10% (w/w) PVA solution, 15 kV voltage, 15 cm spinning distance, and 600 rpm roller speed. Also, the adsorption performance of molecular imprinting chromogenic membrane was investigated in detail, showing a higher adsorption capacity of 33.16 μg cm −2 and maximum imprinting efficiency of 2.30 under the best recognition conditions of 315 μL ninhydrin, 0.25% (w/w) BDO, and 0.4 cm sensing distance, as well as a short adsorption equilibrium time of 40 min. In addition, three amine competitors were discussed to reveal the better selectivity and higher specific recognition ability in the imprinted membrane.HIGHLIGHTS : • The molecular imprinting and coloring structure is constructed in nanofiber membrane with an enhanced specific surface area.• The adsorption on imprinted membrane is visualized by chromogenic reaction between putrescine and ninhydrin to form a threedimensional interactive surface proceeded using the ImageJ software. • The imprinted nanofiber membrane with large area and high pore ratio is applied in detecting target in trace concentration within shortened time.