A liquid marble is a liquid droplet encapsulated in a hydrophobic powder that adheres to the liquid surface. Liquid marbles preparation is very simple – a small amount of liquid is carefully dripped on the layer of hydrophobic powder consisting of nano- or micro particles, which spread spontaneously at the interface liquid/air. This process results in a liquid marble that has some of the properties of a liquid droplet and, at the same time, behaves as a soft solid. Liquid marbles present an alternative to superhydrophobic surfaces because these particles prevent the liquid to wet and contaminate the carrier surface, be it solid or liquid. The present work focuses on the description of basic properties of liquid marbles; also, an overview is given of possible applications of liquid marbles, e.g. for the transport of small volumes of liquids or powders in microfluidics, for the detection of gases or water contamination or as (bio)microreactors.

• Klíčová slova
• tekuté kuličky,
• MeSH
• chemické látky - účinky a užití * MeSH
• hemaglutinační testy metody   MeSH
• hydrofobní a hydrofilní interakce * MeSH
• klinické laboratorní techniky MeSH
• kultivační techniky MeSH
• výzkum MeSH

The design of smart surfaces with externally triggerable water/oil wettability and adhesion represents one of the most up-to-date challenges in the field of material science. In this work, the intelligent surface with electrically triggerable wettability and water/oil adhesion is presented. As a basic material background exhibiting electric field (EF) sensitivity, the piezo-responsive polymethylmethacrylate/polyvinylidenefluoride polymer fibers were used. To expand the available range of water/oil contact angles (CAs) and adhesion, the fibers were grafted with hydrophilic or hydrophobic functional groups using diazonium chemistry. The fiber functionality was evaluated using the static CA and wettability hysteresis measurements (increasing/decreasing drop volume and tilting angles), drops adhesion/repellence and graphite self-cleaning test performed with and without the application of EF. It was found that the proposed method enables tuning the surface wettability in the superhydrophobic/superoleophobic-hydrophilic/oleophilic range and changing of surface properties from low adhesive to high adhesive for water and oil. More convincing results were achieved in the case of fiber surface modification by ADT-C8F17, which may result from a rearrangement of the grated -C6H4C8F17 functional group under the application of EF triggering. Moreover, the triggering which can be performed in the extremely fast way (the surface responds to the EF switching on/off in seconds) was found to be fully reversible. Finally, the additional tests indicate the satisfactory stability of created fiber-based coating against the mechanical treatment.

• MeSH
• adhezivita MeSH
• chytré materiály MeSH
• fluoridy MeSH
• hydrofobní a hydrofilní interakce MeSH
• polymethylmethakrylát MeSH
• smáčivost MeSH
• testování materiálů * MeSH
• Publikační typ
• práce podpořená grantem MeSH

Anastomotic leakage and gastrointestinal obstruction due to formation of peritoneal adhesions are major postoperative complications in colorectal surgery. There are no available materials on the market capable of preventing such complications. The aim of the project is to develop a unique double-layered nanofibrous material to cover the intestinal anastomoses. The material will be composed of synthetic biocompatible and biodegradable polymers and prepared by combining the electrospinning and the electrospraying via NanospiderTM. The inner polymeric fibers will adhere to anastomosis and support healing. The outer anti-adhesive side will be inspired by the natural superhydrophobic lotus leaf structure and thus prevent the adhesions. The materials will be assessed in vitro using NIH/3T3 fibroblasts. The adhesion to tissue will be tested mechanically. The functionality of the material will be described in experimental model of complicated healing of colonic anastomosis on pig with three weeks observation period concluded with evaluation of peritoneal adhesions and anastomotic healing.

Anastomotický leak a poruchy pasáže zažívacím traktem způsobené tvorbou peritoneálních adhezí patří mezi zásadní pooperační komplikace v kolorektální chirurgii. Na trhu nejsou k dispozici materiály, které by tyto komplikace spolehlivě eliminovaly. Cílem projektu je vyvinout unikátní dvouvrstvý nanovlákenný materiál s odlišnými vlastnostmi jednotlivých stran pro krytí chirurgických anastomóz. Materiál se bude skládat ze syntetických biokompatibilních a biodegradabilních polymerů a bude připraven kombinací electrospinningu a electrosprayingu na NanospiderTM. Vnitřní polymerní vlákna přilnou k anastomóze a podpoří hojení. Morfologie vnější antiadhezivní strany bude inspirována nativním superhydrofobním lotosovým povrchem a bude sloužit jako prevence adhezí. Materiály budou analyzovány in vitro testy za použití NIH/3T3 fibroblastů. Přilnavost k tkáni bude testována mechanicky. Funkce materiálu bude popsána na prasečím modelu komplikovaného hojení anastomózy na tračníku s třítýdenní observací zvířat zakončenou systematickým hodnocením peritoneálních adhezí a kvality anastomózy.

• Klíčová slova
• biokompatibilita, biocompatibility, nanovlákna, nanofibers, biodegradabilita, biodegradability, gastrointestinální anastomóza, anastomotický leak, pooperační adheze, abdominální chirurgie, superhydrofobicita, gastrointestinal anastomosis, anastomotic leakage, postoperative adhesion, abdominal surgery, superhydrophobic surface,

• NLK Publikační typ
• závěrečné zprávy o řešení grantu AZV MZ ČR