Synthesis of magnetic electroactive nanomotors based on sodium alginate/chitosan and investigation the influence of the external electric field on the mechanism of locomotion

Abstract

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.

Putting Hybrid Nanomaterials to Work for Biomedical Applications

“…High flexibility; good biocompatibility; and high mechanical degradation-resistance Stretchable bioelectronics for neuroprosthetic applications; matrices for nanocomposites; tissue engineering scaffolds; and implantable devices [24,26] Polysaccharides such as agarose, chitosan, and hyaluronic acid Good biocompatibility and biodegradability; hydrophilicity; and ability to stabilize nanoparticles Controlled release; carriers for drug delivery; wound management; and nanocomposite matrices [69][70][71][72][73][74][75] Molecular imaging probes such as Raman active molecules (trans-1,2-bis(4-pyridyl)ethylene) and aggregation-induced emission luminogens (AIEgens)…”

“…[186] To achieve these goals, the nanomotor must overcome the disturbance from Brownian motion, as well as the environmental drag, to efficiently maneuver toward the target. Externally applied physical fields, such as optical, [20,76,185] acoustic, [187] magnetic, [28][29][30] and electric, [75] trigger and maneuver the movements of nanomotors through either the directly applied forces or generation of local vector fields that control the flow. Nanomotors also gain kinetic energy by interacting with the surrounding environment by either catalytically reacting with fuel chemicals in the medium [188] or binding to specific signal molecules to initiate self-diffusiophoresis, [184] selfelectrophoresis, [189] or bubble propulsion.…”

Putting Hybrid Nanomaterials to Work for Biomedical Applications

“…To achieve these goals, the nanomotor must overcome the disturbance from Brownian motion, as well as the environmental drag, to efficiently maneuver toward the target. Externally applied physical fields, such as optical, [20,76,185] acoustic, [187] magnetic, [28–30] and electric, [75] trigger and maneuver the movements of nanomotors through either the directly applied forces or generation of local vector fields that control the flow. Nanomotors also gain kinetic energy by interacting with the surrounding environment by either catalytically reacting with fuel chemicals in the medium [188] or binding to specific signal molecules to initiate self‐diffusiophoresis, [184] self‐electrophoresis, [189] or bubble propulsion [29,190] .…”

Review of the Applications of Micro/Nanorobots in Biomedicine

“…179 Mafakheri et al constructed a novel electric Janus nanomotor (JNMs) based on SPIONs nanoparticles modified with chitosan (Cs) and sodium alginate (Na/Alg). 196 Zhao et al prepared a magnetic spiral microrobot based on polylactic acid and Fe 3 O 4 nanoparticles (Figure 6i). It exhibits controlled motion under a rotating magnetic field, as well as programmable shape changes in length, diameter, and chirality, which are widely used in the fields of soft robots and biomedical devices.…”

“…When dispersed in an aqueous solution, the JNMs exhibit linear trajectories under DC electric field driven by the self-electro-osmotic mechanism and surface modifications. 196 As shown in Figure 7 (g), Gao et al demonstrated a chemical powered micromotor that can provide power through the reaction of three different fuels: alkali, acid, or hydrogen peroxide. 210 As shown in Figure 7 (h), Wang et al developed a superhydrophobic microrobot that is responsive to multiple stimuli.…”