A synthetically modified hydrophobin showing enhanced fluorous affinity

Hydrophobins are natural surfactant proteins endowed with exceptional surface activity and film-forming capabilities and their use as effective “fluorine-free fluorosurfactants” has been recently reported. In order to increase their fluorophilicity further, here we report the preparation of a unique fluorous-modified hydrophobin, named F-HFBI. F-HFBI was found to be more effective than its wild-type parent protein HFBI at reducing interface tension of water at both air/water and oil/water interfaces, being particularly effective at the fluorous/water interface. F-HFBI was also found to largely retain the exceptionally good capability of forming strong and elastic films, typical of the hydrophobin family. Further studies by interface shear rheology and isothermal compression, alongside Quartz Crystal Microbalance and Atomic Force Microscopy, demonstrated the tendency of F-HFBI to form thicker films compared to the wild-type protein. These results suggest that F-HFBI may function as an effective compatibilizer for biphasic systems comprising a fluorous phase

Integrated microfluidic viscometer for edible oil analysis

Viscosity is a key parameter to discriminate origin, industrial/thermal treatments, and contamination of edible oils. For a number of applications, miniaturized, portable, and single-use tools to monitor oil quality on-field are advisable. Here we propose an easy-to-use, disposable microfluidic device to measure rheology and material properties of oils in extensional capillary flows. The integrated viscometer proposed is able to discriminate between pure oils of different origin and oils mixture. The device consists of a polydimethylsiloxane (PDMS) linear microchannel with an oleophobic functionalization, interfaced to an optical microscope, and a custom made software able to detect the capillary dynamics of the injected fluids. The microfluidic viscometer has been tested with commercial and home-made extravirgin olive oils, with sunflowers oil, with commercial frying oil and home-made mixture. The oleophobic coating, consisting of a fluoropolymer bonded to the PDMS through a protein adhesion layer, is needed to decrease oil adsorption during the flow and to reconstruct the capillary dynamics along the entire length of the microchannel. Beyond calculating absolute values of dynamic viscosity, the chip allows to separate and identify components in oils mixtures thanks to an accurate method of data analysis in the constant pressure region and a correlation with microfluidic viscosities of known oils

CAPILLARY VISCOMETER AND METHOD FOR ANALYSIS OF FLUIDS, IN PARTICULAR OILS

The present invention relates to a cost-efficient, portable and disposable device for monitoring the quality of the oil "on field" and represents a valuable alternative to expensive and less quick traditional systems. We believe that the herein described viscosimeter can be useful for monitoring the quality of cooking oils used in restaurants and public places wherein frying oils are repeatedly used, or when it is necessary to check and validate the oil excellence following the suspected addition of lower quality oils. In addition to the food sector, the invention can be applied in industrial plants for monitoring viscosity variations following chemical/physical treatments (as for instance for assessing the efficiency of regeneration processes)

New amphiphilic copolymers for PDMS-based nanocomposite films with long-term marine antifouling performance

Amphiphilic methacrylate copolymers (Si-co-EF) containing polysiloxane (Si) and mixed poly(oxyethylene)-perfluorohexyl (EF) side chains were synthesized with different compositions and used together with polysiloxane-functionalized nanoparticles as additives of condensation cured nanocomposite poly(siloxane) films. The mechanical properties of the nanocomposite films were consistent with the elastomeric behavior of the poly(siloxane) matrix without significant detriment from either the copolymer or the nanoparticles. Films were found to be markedly hydrophobic and liphophobic, with both properties being maximized at an intermediate content of EF units. The high enrichment in fluorine at the film surface was proven by angle-resolved X-ray photoelectron spectroscopy (AR-XPS). Long-term marine antifouling performance was evaluated in field immersion trials of test panels for up to 10 months of immersion. Both nanoparticles and amphiphilic copolymer were found to be highly effective in reducing the colonization of foulants, especially hard macrofoulants, when compared with control panels. Lowest percentage of surface coverage was 20% after 10 months of immersion (films with 4 wt% copolymer and 0.5 wt% nanoparticles), which was further decreased to less than 10% after exposure to a water jet for 10 s. The enhanced antifouling properties of coatings containing both nanoparticles and copolymer were confirmed by laboratory assays against the polychaete Ficopomatus enigmaticus and the diatom Navicula salinicola

A synthetically modified hydrophobin showing enhanced fluorous affinity

Hydrophobins are natural surfactant proteins endowed with exceptional surface activity and film-forming capabilities and their use as effective “fluorine-free fluorosurfactants” has been recently reported. In order to increase their fluorophilicity further, here we report the preparation of a unique fluorous-modified hydrophobin, named F-HFBI. F-HFBI was found to be more effective than its wild-type parent protein HFBI at reducing interface tension of water at both air/water and oil/water interfaces, being particularly effective at the fluorous/water interface. F-HFBI was also found to largely retain the exceptionally good capability of forming strong and elastic films, typical of the hydrophobin family. Further studies by interface shear rheology and isothermal compression, alongside Quartz Crystal Microbalance and Atomic Force Microscopy, demonstrated the tendency of F-HFBI to form thicker films compared to the wild-type protein. These results suggest that F-HFBI may function as an effective compatibilizer for biphasic systems comprising a fluorous phase.Peer reviewe