3 research outputs found
Zwitterionic nanofibers of super-glue for transparent and biocompatible multi-purpose coatings
Here we show that macrozwitterions of poly(ethyl 2-cyanoacrylate), commonly called Super Glue, can easily assemble into long and well defined fibers by electrospinning. The resulting fibrous networks are thermally treated on glass in order to create transparent coatings whose superficial
morphology recalls the organization of the initial electrospun mats. These textured coatings are characterized by low liquid adhesion and anti-staining performance. Furthermore, the low friction coefficient and excellent scratch resistance make them attractive as solid lubricants. The inherent
texture of the coatings positively affects their biocompatibility. In fact, they are able to promote the proliferation and differentiation of myoblast stem cells. Optically-transparent and biocompatible
coatings that simultaneously possess characteristics of low water contact angle hysteresis, low friction and mechanical robustness can find application in a wide range of technological sectors, from
the construction and automotive industries to electronic and biomedical devices
COCONUTīøAn Efficient Tool for Estimating Copolymer Compositions from Mass Spectra
The accurate characterization of
synthetic polymer sequences represents
a major challenge in polymer science. Matrix-assisted laser desorption/ionization
time-of-flight mass spectrometry (MALDI-TOF MS) is frequently used
for the characterization of copolymer samples. We present the COCONUT
software for estimating the composition distribution of the copolymer.
Our method is based on Linear Programming and is capable of automatically
resolving overlapping isotopes and isobaric ions. We demonstrate that
COCONUT is well suited for analyzing complex copolymer MS spectra.
COCONUT is freely available and provides a graphical user interface
Synthesis of Highly Fluorescent Copper Clusters Using Living Polymer Chains as Combined Reducing Agents and Ligands
We present the synthesis of colloidally stable ultrasmall (diameter of 1.5 Ā± 0.6 nm) and fluorescent copper clusters (Cu-clusters) exhibiting outstanding quantum efficiencies (up to 67% in THF and approximately 30% in water). For this purpose, an amphiphilic block copolymer poly(ethylene glycol)-<i>block</i>-poly(propylene sulfide) (MPEG-<i>b</i>-PPS) was synthesized by living anionic ring-opening polymerization. When CuBr is mixed with the living polymer chains in THF, the formation of Cu-clusters is detected by the appearance of the fluorescence. The cluster growth is quenched by the addition of water, followed by THF removal. The structural features of the MPEG-<i>b</i>-PPS copolymer control the cluster formation and the stabilization: the poly(propylene sulfide) segment acts as coordinating and reducing agent for the copper ions in THF, and imparts a hydrophobic character. This hydrophobic block protects the Cu-clusters from water exposure, thus allowing to obtain a stable emission in water. The PEG segment instead provides the hydrophilicity, rendering the Cu-clusters water-soluble. To obtain fluorescent and stable Cu-clusters exhibiting outstanding quantum efficiencies, the removal of the excess of free polymer and copper salt was crucial. The Cu-clusters are also colloidally and optically stable in physiological media and showed bright fluorescence even when taken up by HeLa cells, being noncytotoxic when administered at a Cu dose between 10 nM and 1.6 Ī¼M. Given the very small size of the Cu-clusters, localization and fluorescent staining of cell nucleus is achieved, as demonstrated by confocal cell imaging performed at different Cu-cluster doses and at different incubation temperatures