In this work, we report the design and synthesis of internal energy-driven Janus nanomotors (JNMs), which are composed of certain reactive materials that are capable of converting chemical energy in the backbone of nanomotors into kinetic energy. For this purpose, superparamagnetic iron oxide nanoparticles (SPIONs) with the anisotropic surface were obtained via a Pickering emulsion. Modified chitosan (as hydrophilic polymer) and functionalized polycaprolactone (as hydrophobic domain) were covalently linked to the surface of bi-functional SPIONs to produce Janus nanoparticles (JNPs). Then, the CALB enzyme was loaded in the PCL hemisphere of JNPs to form the Janus nanomotor. When nanomotors are placed in the phosphate-buffered saline solution, the driving force for motion is provided by the decomposition of polyester into monomers and oligomers on one side of the JNMs. The trajectories of the nanomotors were recorded under different circumstances by a video microscope and analyzed by the mean squared displacement. The results show that the velocity of JNMs increases with an increasing percentage of the loaded enzyme. In addition, the diffusion coefficient enhances up to 87.67% in compared with nanoparticles without enzyme. Controlling the motion direction of JNMs by an external magnetic field is also possible, due to the presence of SPIONs.

In this paper, we report a novel electric-driven Janus nanomotor (JNMs) based on SPIONs nanoparticle decorated with chitosan (Cs) and sodium alginate (Na/Alg) using the Pickering emulsion method. The JNMs dispersed in aqueous media exhibit linear trajectories under DC electric field, and the driving force is attributed to the self-electro-osmotic mechanism and surface modifications. This study offers an approach to remotely control the motion modes of the JNMs, including start, stop, directional and programmable motion, which can be advantageous for various application scenarios. The diffusion coefficient and velocity of the JNMs were investigated through mean square displacement analysis for single particle of JNMs, both in distilled water and in the presence of different di and trivalent metal cations (Fe3+, Al3+, Ba2+, Ca2+ and Mg2+) as crosslinking agents, as well as monovalent salts (LiCl and KCl). The results revealed that the motion of JNMs was fastest in the presence of Fe3+ as crosslinker agent (about 7.2181 μm2/s) due to its higher charge than equimolar Na+ . Moreover, it was demonstrated that increasing the ionic strength led to relatively higher speeds of JNMs, as the solution polarity increased and, as a result, the driving force of electro-osmoesis enhanced.

The biobased renewable monomer 2,5-diformylfuran is polymerised using various N-heterocyclic carbene (NHC) catalysts in dimethyl sulfoxide (DMSO) affording a low molar mass polymer. It is shown that catalyst structure as well as the temperature and time the polymerization is running have a noticeable effect on its molar mass. The obtained material is characterized by nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). An attempt at chain extension with diamine leads to precipitation of the polymer. This new biobased polymer material might be useful as a sustainable resin.