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Silver nanoparticles have attracted great attention in the biomedical research field, especially in cancer theranostics. In this study, we developed a synthesis method for silver nanoparticles in the solid state using high-speed vibration milling, in which biocompatible polymers such as poly(vinylpyrrolidone), poly(ethylene glycol) and chitosan were used for the reduction of the silver salt. The synthesis of the size-tunable silver nanoparticles was performed at room temperature and no surfactants to direct the anisotropic growth of the nanoparticles were required. The formation of the nanoparticles was studied using UV-visible and Fourier transform infrared spectroscopy as well as transmission electron microscopy. The synthesized nanoparticles showed an average diameter ranging from 3.1 ± 1.4 to 22.8 ± 5.8 nm. In addition, the anticancer activity of these silver nanoparticles was assessed using cytotoxicity studies with human breast adenocarcinoma (MCF-7), human lung adenocarcinoma (NCI-H358) and mouse embryonic fibroblast (NIH-3T3) cell lines. Accordingly, an effective suppression of the proliferation of cell growth was found. © 2016 Society of Chemical Industry

Among carbon-based nanomaterials such as fullerenes, carbon nanotubes and nanodiamonds, the latter are good candidates as prospective materials in the future due to their potential physical, chemical and biological properties. Thus, nanodiamonds were wrapped with biocompatible polymers in the solid state. The dispersibility of the polymer-wrapped nanodiamonds in water was investigated with respect to reaction time and mass ratio of the polymers during the wrapping process. The dispersibility of the materials was monitored using UV spectroscopy, and the size distribution of the polymer-wrapped nanodiamonds was analyzed using high-resolution transmission electron microscopy and dynamic light scattering measurements. In addition, molecular modeling calculations were performed. Finally, the best dispersion for the polymer-wrapped nanodiamonds in water was found for a reaction time of 120 min. Copyright © 2012 Society of Chemical Industry

The commercial sunscreen agent Tinosorb S (TS) is a promising oil-soluble broad spectrum UV filter. Here, we report for the first time a water-dispersible inclusion complex of TS using cucurbituril. The synthesis was carried out via a supramolecular approach in the solid state by using the high-speed vibration milling technique. The formation and the photophysical properties of the solid inclusion complex were investigated by spectroscopic techniques such as UV–vis spectrophotometry, Fourier-transform infrared and solid-state proton nuclear magnetic resonance spectroscopy as well as by thermal gravimetric analysis and X-ray diffractometry. An increase in the absorbance and a shift of the maximum absorption from 380 nm to 345 nm for the inclusion complex were observed in comparison to the precursor complex TS. The stochiometric ratio of cucurbituril and TS in the inclusion complex was found to be 2:1

Silver nanoparticles have been used for a long time and recently various methods have been additionally developed for their production. Here we report for the first time a solid-state highspeed vibration milling method for the synthesis of silver nanoparticles, in which poly-(vinylpyrrolidone) is used for the reduction of the silver salt. The synthesis is performed at room temperature and no surfactant to direct the anisotropic growth of the nanoparticles is required. The formation of the nanoparticles was studied by UV―Visible spectroscopy, transmission electron microscopy, and powder X-ray diffraction techniques. The nanoparticles synthesized were found to be uniform in size and shape with an average diameter of less than 5 nm. In addition, the antimicrobial activity of these silver nanoparticles was investigated against Escherichia coli and found to be positive.

A new series of biphenylene ethynylene co-polymers, poly(2,5-dialkoxy-4-phenyleneethynylene-4,4-biphenyleneethynylene)s of the general formula [-C ≡C-4-C6H4-C6H4-4-C ≡C-C6H2(2,5-OR)2-]n (R = C4H9 P1, C8H17 P2) has been synthesized using a palladium/copper catalyzed coupling reaction between HC ≡C-4-C6H4-C6H4-4-C ≡C-H and IC6H2(2,5-OR)2I. The new co-polymer [-C ≡C-C6H2(2,5-OC8H17)2-C ≡C-C6H2(2,5-OC4H9)2-]n P5 has also been formed where different alkoxy substituents are present on alternate arene rings in the same polymer backbone. All the polymers were characterized by IR, 1H and 13C NMR spectroscopy and by GPC. The model compounds C6H5-4-C6H4-C≡C-C6H2(2,5-OR)2-4-C6H4-C6H5 (R = C4H9 M1, C8H17 M2) have also been prepared by the reaction between C6H5-4-C6H4-C≡CH and IC6H2(2,5-OR)2I. Single crystal X-ray structures of M1, M2 and Me3Si-C≡C-4-C6H4-C6H4-4-C≡C-SiMe3 were determined with a view to obtain a better understanding of the molecular and intermolecular interactions in the solid state which has been used to explain the optical properties of the polymers derived from them. The absorption and photoluminescence spectra of the polymers, P1, P2 and P5 showed that the lowest energy band is blue shifted due to the introduction of biphenylene fragments into the alkoxy substituted poly(ethynylenephenylene)s.

Gold nanoparticles have attracted considerable interest due to their salient properties and many methods for their fabrication have been developed. In this study, for the first time a solid state method for their synthesis has been designed and developed. Thus, high-speed vibration milling has been used for the synthesis of gold nanoparticles, where sodium borohydride was used for the reduction of the gold salt. Poly(vinylpyrrolidone) was used as a protecting agent for the gold nanoparticles synthesized. This system used for the synthesis of the gold nanoparticles required only room temperature and yielded mostly polyhedral nanoparticles with diameters ranging from 6.3 ± 2.1 to 27.9 ± 6.2 nm. The size of the nanoparticles was tunable by varying different reaction parameters such as the molar mass of polymer protecting agent, reaction time, and the mass ratio of gold precursor and polymer protecting agent. The nanoparticles were characterized by UV-visible spectroscopy, Fourier transform-infrared spectroscopy, transmission electron microscopy, and powder X-ray diffraction techniques.

A series of cis-platinum ethynyl complexes with the general formula cis-[Pt(dppe)(C[triple bond]CR)2](dppe = 1,2-bis(diphenylphosphino)ethane; R = C6H4-p-NO2 1, C6H4-p-CH3 2, C6H4-p-C[triple bond]CH 3 and C6H4-p-C6H4-p-C[triple bond]CH 4) have been prepared by the coupling reaction of cis-[Pt(dppe)Cl2] with two equivalents of the appropriate alkyne. The new complexes have been fully characterized by spectroscopic techniques, and the cis square planar arrangement at the platinum centre has been confirmed by single-crystal X-ray diffraction studies of complexes 1, 2 and 4. The absorption spectra of the complexes 1-4 are dominated by a pi--pi* band that contains some platinum (n + 1) p orbital character. The position of the band is dependent on the electron donating or withdrawing properties of the ethynyl substituents, R. Complex 1 displays a triplet emission in the green, at room temperature, while complexes 2-4, display singlet emissions in the blue. Again, the difference can be attributed to the nature of the R substituents.