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Poly(ɛ-caprolactone)-silver nanocomposite were prepared by two main methods of metal-polymer nanocomposite preparation approaches, in situ and ex situ methods, by electrospinning. Effective parameters on electrospun nanofibers were optimized by Design Expert, CCD method. Using in situ and ex situ methods, effect of incorporating silver nanoparticle into Poly(ɛ-caprolactone) on conductivity, average fiber diameter, morphology of nanofiber mats and antibacterial properties were investigated. According to Field Emission Scanning Electron Microscopy (FESEM) and Energy-Dispersive X-ray Spectroscopy (EDX) analysis, average fibers diameters decreased by increasing incorporated Ag nanoparticles. Conductivity results confirmed the higher content of silver nanoparticles in in situ samples. Antibacterial test was performed against two bacteria types: Staphylococcus-aureus and Escherichia-coli. Due to higher content and smaller size of Ag nanoparticles incorporated in nanofibers, silver-loaded PCL electrospun nanofibers obtained by in situ method showed higher antibacterial efficiency in comparison to the ex situ samples. Moreover, Ag particles had more effects on Staphylococcus aureus due to sensitive membrane of this type of bacteria. In vivo study has proved that in situ samples improved the wounds on Wistar rat lateral part of body skin. Antibacterial and in vivo results showed that PCL-Ag nanofiber mats obtained by in situ method are suitable for medical applications. To achieve low average fibers diameters, in situ method was more applicable than ex situ one. Antibacterial properties of fibers mat prepared by in situ method was more effective than ex situ one against both Staphylococcus aureus and Escherichia coli bacteria. Effectiveness of AgNPs in both in situ and ex situ methods on Staphylococcus aureus was more than Escherichia coli. In situ and ex situ nanofibers have proved to be more effective in in vivo test and showed better performance than pure PCL nanofiber scaffolds. [ABSTRACT FROM AUTHOR]

Drinking water—a vital part of our ecosystem—is often exposed to contamination through industrialization. Halogenated compounds, for example, trihalomethanes (THMs), are among the most common contaminants, being by‐products of water chlorination/treatment. The carcinogenic and health effects of these compounds have motivated scientists to work on the accurate detection of THMs down to 80 ppb in treated water. Here, a superhydrophobic syndiotactic polypropylene (sPP) nanofiber mat is used to preconcentrate THMs in environmental water samples, and subsequently, detect them using a well‐known colorimetric reaction chemistry. The reaction chemistry yields a visible red/pink chromophore under visible light absorption. This reaction occurs when the preconcentrated THM becomes trapped in the liquid phase of the reaction chemistry, on the surface of the sPP fibers. This fiber mat is electrospun in a way which results in a large water contact angle >150°—allowing the working sensitivity of the reaction chemistry to be heightened and lowering the detection limit. The resulting color change can be analyzed via a simple quantitative color intensity analysis utilizing widely‐available software, measuring the THM content in water as low as 0.8 ppb. This cost‐effective and selective method was incorporated into a portable device, enabling on‐site users to evaluate the quality of drinking water. [ABSTRACT FROM AUTHOR]