Synthesis, luminescent and drug-release properties of SiO2@Y2O3:Eu hollow mesoporous microspheres

Abstract

SiO 2 @Y 2 O 3 :Eu hollow mesoporous microspheres were prepared by coating luminescent Y 2 O 3 :Eu 3? particles onto uniform silica spheres using melamine formaldehyde microspheres as sacrificial templates. Various approaches including X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared, thermogravimetric and differential thermal analysis, photoluminescence spectroscopy and N 2 adsorption/desorption were used to characterize the samples. The results indicate that Y 2 O 3 :Eu 3? particles have been coated onto the hollow silica spheres with 300 nm thickness shell, and the composite microspheres exhibit mesoporous characteristics and have spherical morphology. Upon ultraviolet excitation, the composite shows the characteristic 5 D 0 -7 F 1-4 red emission lines of Eu 3? even after loading of the model drug. In addition, drug release tests suggest that the composite has a controlled drug release property with ibuprofen as the model drug.

Self‐Templating Approaches to Hollow Nanostructures

“…Some intrinsic features of hollow nanostructures, such as the large surface area, low density, and abundant inner void space, have been harnessed in many energy‐related applications, such as batteries, supercapacitors, and catalysis . They may be employed as nanoscale containers to load small organic molecules, such as pharmaceutical compounds, proteins, enzymes, DNA, or even nanoparticles in the void space . The shell can protect these active materials against the chemical interference from the outside.…”

Large-Scale Fabrication of Hollow Pt3Al Nanoboxes and Their Electrocatalytic Performance for Hydrogen Evolution Reaction

“…Hollow and porous nanostructures have received considerable attention for their various applications in catalysis, energy conversion, and storage. − The first hollow structure based on silica was reported by Caruso and coworkers in 1998; since then, various hollow nano- or/and microstructures with different morphologies such as ellipsoids, cubes, rods, and wires have been successfully fabricated via the template approach. − Specifically, the following templating strategies have been employed so far: (1) hard templating, which involves coating a layer of desired materials on the surface of a hard template with specific shapes, followed by selective removal of the template to obtain the hollow structure; − (2) soft templating, during which soft matters such as gas bubbles, emulsion, − and vesicles/micelles , are utilized as templates; and (3) self-templating, which is developed based on different principles, including Ostwald ripening, , galvanic replacement, Kirkendall effect, and surface-protected etching. , However, most hollow structures fabricated by these strategies are metal oxides or chalcogenides and carbon spheres, − and it remains a technical challenge to fabricate hollow noble metal–transition metal intermetallic compound nanostructures, particularly on a large scale.…”

Synthesis and Applications of Nanocontainers and Nanorattles

“…in theranostics [18] where imaging agents for diagnosis (fluorescent dyes or particles, but also MRI, [19] ultrasound [20] or photoacoustic imaging [21] contrast agents) are combined with drug delivery or other therapeutic approaches in one product. In this sense, hollow mesoporous silica, [22] polymeric vesicles, [23] and different NR [12] are loaded with anticancer drugs, [24] ibuprofen, [25] enzymes, [26] or siRNA [27] and are sometimes even modified to achieve a stimuliresponsive drug release activated by temperature, [26] pH, [28] enzymes, [29] or the K + concentration. [30]…”