Many types of polymer nanofibers have been introduced as artificial extracellular matrices. Their controllable properties, such as wettability, surface charge, transparency, elasticity, porosity and surface to volume proportion, have attracted much attention. Moreover, functionalizing polymers with other bioactive components could enable the engineering of microenvironments to host cells for regenerative medical applications. In the current brief review, we focus on the most recently cited electrospun nanofibrous polymeric scaffolds and divide them into five main categories: natural polymer-natural polymer composite, natural polymer-synthetic polymer composite, synthetic polymer-synthetic polymer composite, crosslinked polymers and reinforced polymers with inorganic materials. Then, we focus on their physiochemical, biological and mechanical features and discussed the capability and efficiency of the nanofibrous scaffolds to function as the extracellular matrix to support cellular function.

Firecracker-like ZnO hierarchical structures (ZnO HS1) were synthesized by combining electrospinning with hydrothermal methods. Flower-like ZnO hierarchical structures (ZnO HS2) were prepared by a hydrothermal method using ultrasound-treated ZnO nanofibers (ZnO NFs) as raw material which has rarely been reported in previous papers. Scanning electron microscope (SEM) and transmission electron microscope’s (TEM) images clearly indicated the existence of nanoparticles on the ZnO HS2 material. Both gas sensors exhibited high selectivity toward H2S gas over various other gases at 180 °C. The ZnO HS2 gas sensor exhibited higher H2S sensitivity response (50 ppm H2S, 42.298) at 180 °C than ZnO NFs (50 ppm H2S, 9.223) and ZnO HS1 (50 ppm H2S, 17.506) gas sensors. Besides, the ZnO HS2 sensor showed a shorter response time (14 s) compared with the ZnO NFs (25 s) and ZnO HS1 (19 s) gas sensors. The formation diagram of ZnO hierarchical structures and the gas sensing mechanism were evaluated. Apart from the synergistic effect of nanoparticles and nanoflowers, more point–point contacts between flower-like ZnO nanorods were advantageous for the excellent H2S sensing properties of ZnO HS2 material.

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Silver@graphene oxide nanocomposite was synthesized through an efficient approach, characterized by FTIR, EDX, and TEM instruments and then was used as adsorbent for imidacloprid removal from water in batch procedure. Effective variants such as contact time, pH, adsorbent dosage, and initial concentration of imidacloprid on procedure by two methods, one at a time and experimental design methods, were studied. Results in optimum conditions based on one at a time experiments is removal of 63% of the pesticide from 50 mL water containing 10 mg/L of imidacloprid by 0.03 g of the adsorbent at pH = 6.6 after 60 min while, experimental design method predict similarity results, 66% uptake of the poison by 0.06 g of the adsorbent in pH = 8. Kinetics and isotherm for adsorption processes follows Freundlich and pseudo-second-order models. Results confirm that Ag@graphene oxide nanocomposite can be applicable for removal of imidacloprid from real polluted water.