Search results for "Anus"

Il contributo di Marsilio Ficino al testo di Ermia neoplatonico e l'esemplare greco da lui utilizzato

2010

In Silico Design Enables the Rapid Production of Surface-Active Colloidal Amphiphiles

2020

A new technology platform built on the integration of theory and experiments to enable the design of Janus colloids with precision control of surface anisotropy and amphiphilicity could lead to a disruptive transformation in the next generation of surfactants, photonic or phononic materials, and coatings. Here, we exploit molecular dynamics (MD) simulations to guide the rational design of amphiphilic polymer Janus colloids by Flash NanoPrecipitation (FNP), a method capable of the production of colloids with complex structure without the compromise of reduced scalability. Aided by in silico design, we show in experiments that amphiphilic Janus colloids can be produced using a unique blend of…

Comparative evaluation of the impact on endothelial cells induced by different nanoparticle structures and functionalization

2015

In the research field of nanoparticles, many studies demonstrated a high impact of the shape, size and surface charge, which is determined by the functionalization, of nanoparticles on cell viability and internalization into cells. This work focused on the comparison of three different nanoparticle types to give a better insight into general rules determining the biocompatibility of gold, Janus and semiconductor (quantum dot) nanoparticles. Endothelial cells were subject of this study, since blood is the first barrier after intravenous nanoparticle application. In particular, stronger effects on the viability of endothelial cells were found for nanoparticles with an elongated shape in compa…

Inorganic Janus particles for biomedical applications.

2014

Based on recent developments regarding the synthesis and design of Janus nanoparticles, they have attracted increased scientific interest due to their outstanding properties. There are several combinations of multicomponent hetero-nanostructures including either purely organic or inorganic, as well as composite organic–inorganic compounds. Janus particles are interconnected by solid state interfaces and, therefore, are distinguished by two physically or chemically distinct surfaces. They may be, for instance, hydrophilic on one side and hydrophobic on the other, thus, creating giant amphiphiles revealing the endeavor of self-assembly. Novel optical, electronic, magnetic, and superficial pro…

Microfluidic Preparation of Liquid Crystalline Elastomer Actuators

2018

This paper focuses on the microfluidic process (and its parameters) to prepare actuating particles from liquid crystalline elastomers. The preparation usually consists in the formation of droplets containing low molar mass liquid crystals at elevated temperatures. Subsequently, these particle precursors are oriented in the flow field of the capillary and solidified by a crosslinking polymerization, which produces the final actuating particles. The optimization of the process is necessary to obtain the actuating particles and the proper variation of the process parameters (temperature and flow rate) and allows variations of size and shape (from oblate to strongly prolate morphologies) as wel…

Silanization as a versatile functionalization method for the synthesis of polymer/magnetite hybrid nanoparticles with controlled structure

2016

We compare the use of different trimethoxysilane compounds for the surface functionalization of magnetite nanoparticles and their subsequent incorporation in hybrid particles formed by in situ polymerization. For the encapsulation of inorganic nanoparticles via miniemulsion polymerization, surface functionalization of the inorganic material is necessary to hydrophobize the otherwise hydrophilic inorganic material and to compatibilize it with the polymer. Hydrophobic magnetite nanoparticles are usually prepared by surface functionalization with oleic acid, which leads to effective hydrophobization, but offers only limited control over the structure of the hybrid particles. As an alternative,…

Biocalcite, a multifunctional inorganic polymer: Building block for calcareous sponge spicules and bioseed for the synthesis of calcium phosphate-bas…

2014

Calcium carbonate is the material that builds up the spicules of the calcareous sponges. Recent results revealed that the calcium carbonate/biocalcite-based spicular skeleton of these animals is formed through an enzymatic mechanism, such as the skeleton of the siliceous sponges, evolutionarily the oldest animals that consist of biosilica. The enzyme that mediates the calcium carbonate deposition has been identified as a carbonic anhydrase (CA) and has been cloned from the calcareous sponge species Sycon raphanus. Calcium carbonate deposits are also found in vertebrate bones besides the main constituent, calcium phosphate/hydroxyapatite (HA). Evidence has been presented that during the init…

Nanophase Segregation of Self-Assembled Monolayers on Gold Nanoparticles

2017

International audience; Nanophase segregation of a bi-component thiol self-assembled monolayer is predicted using atomistic molecular dynamics simulations and experimentally confirmed. The simulations suggest the formation of domains rich in acid-terminated chains, on one hand, and of domains rich in amide-functionalized ethylene glycol oligomers, on the other hand. In particular, within the amide-ethylene glycol oligomers region, a key role is played by the formation of inter-chain hydrogen bonds. The predicted phase segregation is experimentally confirmed by the synthesis of 35 and 15 nm gold nanoparticles functionalized with several binary mixtures of ligands. An extensive study by trans…

Interfacial Self-Assembly of Amphiphilic Dual Temperature Responsive Actuating Janus Particles

2018

Controlling Janus Nanodisc Topology through ABC Triblock Terpolymer/Homopolymer Blending in 3D Confinement

2021

Janus particles have drawn considerable interest as colloidal surfactants, microswimmers, and building blocks for colloidal lattices. So far, research primarily focused on spherical Janus particles for which a number of fabrication methods are well established. Janus particles with geometric anisotropy offer shape-dependent properties in addition to surface anisotropy, but their synthesis is more challenging. Here, we report a variety of polymeric Janus nanoparticles synthesized from ABC triblock terpolymer microphases in microemulsion droplets. Evaporation-induced assembly of the ABC triblock terpolymers led to prolate microparticles with A/C lamellae stacked along the particle’s major axi…