Photophysical Details and O2-Sensing Analysis of a Eu(III) Complex in Polymer Composite Nanofibers Prepared by Electrospinning

An as-synthesized Eu(III) complex, denoted as Eu(N-DPNQ)(TTD)3, was prepared and characterized, and the antenna mechanism between these ligands and central metal emitter was studied. Here DPNQ means 10-ethyl-10H-indolo [2′,3':5,6]pyrazino[2,3-f][1,10]phenanthroline and TTD is 4,4,4-trifluoro-1-(thiophen-2-yl)butane-1,3-dione. We find that Eu(N-DPNQ)(TTD)3 emission intensity dependents on oxygen concentration, and O2-sensing skill of Eu(N-DPNQ)(TTD)3 in polymer composite nanofibers of poly (vinylpyrrolidone) (PVP) prepared by electrospinning is investigated. Results reveal that the emission quenching of Eu(N-DPNQ)(TTD)3 is caused by the ground state (triplet) oxygen quenching on antenna ligands triplet state. The Eu(N-DPNQ)(TTD)3 doped composite nanofiber with a loading level of 6 wt% exhibits the best result with sensitivity of 2.43 and response time of 10 s, along with linear response.

Electrospun ZnSnO3/ZnO Composite Nanofibers and Its Air-Sensitive Properties

In this work, a novel heterojunction based on ZnSnO3/ZnO nanofibers was prepared using electrospinning method. The crystal, structural and surface compositional properties of sample based on ZnSnO3 and ZnSnO3/ZnO composite nanofibers were investigated by X-ray diffractometer (XRD), Scanning electron microscope (SEM), X-ray photoelectron spectrometer (XPS) and Brunauer-Emmett-Teller (BET). Compared to pure ZnSnO3 nanofibers, the ZnSnO3/ZnO heterostructure nanofibers display high sensitivity and selectivity response with fast response towards ethanol gas at low operational temperature. The sensitivity response of sensor based on ZnSnO3/ZnO composite nanofibers were 19.6 towards 50 ppm ethanol gas at 225°C, which was about 1.5 times superior than that of pure ZnSnO3 nanofibers, which can be owed mainly to the presence of oxygen vacancies and the synergistic effect between ZnSnO3 and ZnO.

Development of poly(vinyl alcohol) / chitosan / aloe vera gel electrospun composite nanofibers as a novel sorbent for thin-film micro-extraction of pesticides in water and food samples followed by HPLC-UV analysis

Herein, a novel composite of poly(vinyl alcohol) (PVA)/citric acid (CA)/ chitosan (CS)/ aloe vera gel (AV) was fabricated via the electrospinning technique followed by a thermal treatment. The resultant composite...

Adsorption, and controlled release of doxorubicin from cellulose acetate/polyurethane/multi-walled carbon nanotubes composite nanofibers

The cellulose acetate (CA)/poly (ε-caprolactone diol)/poly (tetramethylene ether) glycol-polyurethane (PCL-Diol/PTMG-PU)/multi-walled carbon nanotubes (MWCNTs) composite nanofibers were prepared via two-nozzle electrospinning on both counter sides of the collector. The performance of synthesized composite nanofibers was investigated as an environmental application and anticancer delivery system for the adsorption/release of doxorubicin (DOX). The synergic effect of MWCNTs and DOX incorporated into the nanofibers was investigated against LNCaP prostate cancer cells. The status of MWCNTs and DOX in composite nanofibers was demonstrated by SEM, FTIR and UV-Vis determinations. The adsorption tests using nanofibrous adsorbent toward DOX sorption was evaluated under various DOX initial concentrations (100-2000 mgL-1 ), adsorption times (5-120 minutes), and pH values (pH:2-9). Due to the fitting of isotherm and kinetic data with Redlich-Peterson and pseudo-second order models, both chemisorption and surface adsorption of DOX molecules mechanisms have been predicted. The drug release from both nanofibers and MWCNTs-loaded nanofibers was compared. The better drug sustained release profiles verified in the presence of composite nanofibers. LNCaP prostate cancer and L929 normal cells were treated to investigate the cytotoxicity and compatibility of synthesized composite nanofibers. The apoptosis/necrosis of hybrid nanofibers and MWCNTs loaded-nanofibers was investigated. The obtained results demonstrated the synergic effects of MWCNTs and DOX loaded-nanofibers on the LNCaP prostate cancer cells death.