The Development of Smart, Multi-Responsive Core@Shell Composite Nanoparticles

Abstract

The unique optical, magnetic, and electronic properties of metal nanoparticles NPs give rise to photothermal, therapeutic, and electronic device applications, correspondingly. On the other hand, the limited range of the properties of simple spherical metal NPs has complicated their ability to function in many of these applications. Therefore, this chapter starts by reviewing a specific type of NP that can be classified into three main groups silica coated with metal silica@metal NPs, metal coated with silica metal@silica NPs, and other similar forms of core@shell structures. The objective of this review is to introduce the concept of multi-responsive core@shell nanoparticles. More specifically, this chapter highlights "smart" core@shell composite NPs having multiple response mechanisms e.g., temperature, light, and/or an applied magnetic field due to the ability of these systems to perform a task by remotely responding to stimuli. Additionally, hydrogel-coated metal@silica NPs, with the ability to store drugs in a mesoporous silica m-silica interlayer, are examined because these nanomaterials potentially provide substantial advantages for carrying cargos to targeted sites. To demonstrate this capability, we examine recent research that provided initial tests of composite NPs with a pH-and temperature-responsive hydrogel coating, including the application of an underlying m-silica interlayer to improve the capacity of these NPs to load and release small molecules.

Encapsulation of Emulsion Droplets with Metal Shells for Subsequent Remote, Triggered Release

“…Additionally, very good control over the thickness of the deposited gold film was demonstrated by simply varying the concentration of gold salt used in the emulsion continuous phase (Figure ). This is particularly useful as it allows for control of the overall metal-shell microcapsule density, optical properties (such as optical resonance), , and also mechanical stability. The size distribution of the emulsion template used in this case is known, which allows us to calculate the total oil/water interfacial area in the sample and therefore, assuming that all gold salt is reduced and deposited onto the emulsion droplets, to also calculate the metal film thickness and corresponding metal-shell microcapsule density for all six samples.…”

Magnetic Nanoparticles: From Synthesis to Theranostic Applications

“…Recently, interest in using nanoparticles of metals like silver, gold, palladium, platinum, bismuth, zinc, molybdenum, manganese, copper, and iron has developed in diverse biomedical applications like biosensors, sustained/target delivery of the drug, photothermal therapy (PTT), bioimaging, and hyperthermia. − The nanoparticle’s variation, stabilization, and modification by particular functionalization groups permit the binding of drugs, ligands, and other antibodies to them, which makes the structures more favorable theranostic agents. The most fascinating theranostic nanovectors among inorganic nanomaterials are IONPs because of their distinctive physicochemical characteristics at the nanoscale.…”

Controlling optical trapping of metal–dielectric hybrid nanoparticles under ultrafast pulsed excitation: a theoretical investigation

“…These novel materials enable ne-tuning of the optical properties according to the specic needs of the experiment by integrating the properties of both the parent materials. [19][20][21] These metal-dielectric core-shell particles have other advantages such as improved chemical and physical properties, catalytic properties, improved biocompatibility, etc., which makes them good candidates for bio-conjugated experiments. [22][23][24] A number of techniques and procedures emerged for fabrication of these particles with a controllable composition and morphology, [25][26][27] opening up the possibilities of using these particles in the aforementioned wide range of applications.…”

“…These novel materials enable fine-tuning of the optical properties according to the specific needs of the experiment by integrating the properties of both the parent materials. 19–21 These metal–dielectric core–shell particles have other advantages such as improved chemical and physical properties, catalytic properties, improved biocompatibility, etc. , which makes them good candidates for bio-conjugated experiments.…”