Design Of Hybrid Electrospun Nanofibers Comprising A Xerogel Functionalized With A Fluorescent Dye For Application As Optical Detection Device

The electrospinning technique allows the production of micro- and nanofibers, which can be used to obtain membranes with high surface area and high porosity. These properties are of importance with regard to the use of nanomaterials in the design of optical detection devices. In this Article, electrospun blends comprising poly(ethylene oxide) [PEO] and sodium alginate [SA], with and without the adsorption of a fluorescent dye (4-[4-(dimethylamino)styryl]-1-methypyridinium iodide, [DSMI]), were prepared and characterized. PEO/SA/DSMI nanofibers presented higher fluorescence emission intensity and higher absolute quantum yield compared to DSMI in solution. However, DSMI was leached into the solution during the nanofiber cross-linking process. Thus, in order to avoid this leaching, a xerogel [XSB30] was modified with 4-[4-(dimethylamino)styryl]pyridine [DMASP] to generate covalently anchored dye units [XSB30-DMASP]. The resulting novel material was then electrospun with PEO/SA. Cross-linking of the electrospun hybrid PEO/SA/XSB30-DMASP nanofibers produced a material exhibiting an increase in both fluorescence emission and absolute quantum yield. Cellulose acetate [CA] was used for comparison because of its solubility in acetone, a less polar solvent that leads to a better distribution of the xerogel. These electrospun systems associated with fluorescent dyes have the potential to be applied in the design of logical gates and chemical sensors.