Magnetic/gold nanoparticle functionalized biocompatible microcapsules with sensitivity to laser irradiation

Abstract

Nanocomposite microcapsules with both gold and magnetite nanoparticles in the shell were prepared in a layer-by-layer procedure using biocompatible polyelectrolytes and nanoparticles. The process of a nanocomposite multilayer formation was investigated using a quartz crystal microbalance (QCM). In addition, nanocomposite microcapsules were characterized by atomic force microscopy (AFM), transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDX). It is found that the amount of adsorbed nanoparticles is similar for nanoparticles of various sizes, while the concentration of gold nanoparticles in the shell is higher for smaller nanoparticles. Adsorption of gold nanoparticles is found to be more effective than adsorption of magnetic nanoparticles. Multifunctionality of microcapsules is manifested by dual: magnetic and optical responses. Iron oxide nanoparticles embedded in the microcapsule shell allowed for control over capsules positioning by external magnetic fields. Furthermore, the nanocomposite microcapsules could be opened by laser irradiation; these results are of interest for medical and biological applications.

Adsorption of core-shell nanoparticles at liquid–liquid interfaces

“…thermal conductivity, 8 mechanical stability 9 or energy transfer 9 ), or to impart new functions to them (e.g. magnetic 10,11 or triggered release 12,13 ). In parallel, vast efforts have been recently made in order to synthesize and fabricate NPs of controlled shape and functionality 14,15 and to understand how they interact 16 with the aim to direct their assembly into complex structures.…”

Polyelectrolytes: Influence on Evaporative Self-Assembly of Particles and Assembly of Multilayers with Polymers, Nanoparticles and Carbon Nanotubes

“…We note that broad absorption of carbon nanotubes in the visible spectral range [61][62][63][64] and their high light-to-heat conversion efficiency [67] makes them an attractive alternative to non-spherical nanoparticles [94] and nanorods [95,96] in regard to controlling the permeability of polymeric microcapsules [37][38][39][40][41][42][43] and activation of planar films [21][22][23]. We note that results of our work can be used for producing polyelectrolyte multilayers simultaneously functionalized not only with gold and magnetic nanoparticles [97], but also with these nanoparticles and carbon nanotubes. Furthermore, these results can be used for self-assembling particle-based structures as well as for building spherical microcapsules and planar films with a variety of polymers [98] and for increasing multifunctionality of more sophisticated hierarchies of microcapsules [99].…”

“…Besides, aggregates of nanoparticles embedded within biocompatible films can be activated by a near-IR laser [21][22][23]; these effects are based on nanoplasmonic heating of nanoparticles [45][46][47][48][49][50][51][52][53][54][55][56][57]. Additionally, magnetic nanoparticles enable positioning of polyelectrolyte capsules [58], while on the other hand activation is also possible [59]. Carbon nanotubes [60][61][62][63][64][65] are attractive candidates for functionalization, too, because, on the one hand, they enhance mechanical properties [66], while on the other hand, they are found to be extremely efficient absorption centers [67].…”

Layer-by-layer capsules as smart delivery systems of CeO2 nanoparticle-based theranostic agents

“…iron oxide) allows control over the delivery. In the latter case, the shell modification may be carried out using both previously synthesized magnetite nanoparticles [36] and in situ formation of Fe 3 O 4 nanoparticles directly on the capsule shell [37,38]. In the first case, because of the mutual repulsion of charged nanoparticles, their adsorption is limited.…”