Encapsulation of Upconversion Nanoparticles in Periodic Mesoporous Organosilicas

Abstract

(1) Background: Nanomedicine has recently emerged as a promising field, particularly for cancer theranostics. In this context, nanoparticles designed for imaging and therapeutic applications are of interest. We, therefore, studied the encapsulation of upconverting nanoparticles in mesoporous organosilica nanoparticles. Indeed, mesoporous organosilica nanoparticles have been shown to be very efficient for drug delivery, and upconverting nanoparticles are interesting for near-infrared and X-ray computed tomography imaging, depending on the matrix used. (2) Methods: Two different upconverting-based nanoparticles were synthesized with Yb3+-Er3+ as the upconverting system and NaYF4 or BaLuF5 as the matrix. The encapsulation of these nanoparticles was studied through the sol-gel procedure with bis(triethoxysilyl)ethylene and bis(triethoxysilyl)ethane in the presence of CTAB. (3) Results: with bis(triethoxysilyl)ethylene, BaLuF5: Yb3+-Er3+, nanoparticles were not encapsulated, but anchored on the surface of the obtained mesoporous nanorods BaLuF5: Yb3+-Er3+@Ethylene. With bis(triethoxysilyl)ethane, BaLuF5: Yb3+-Er3+ and NaYF4: Yb3+-Er3+nanoparticles were encapsulated in the mesoporous cubic structure leading to BaLuF5: Yb3+-Er3+@Ethane and NaYF4: Yb3+-Er3+@Ethane, respectively. (4) Conclusions: upconversion nanoparticles were located on the surface of mesoporous nanorods obtained by hydrolysis polycondensation of bis(triethoxysilyl)ethylene, whereas encapsulation occurred with bis(triethoxysilyl)ethane. The later nanoparticles NaYF4: Yb3+-Er3+@Ethane or BaLuF5: Yb3+-Er3+@Ethane were promising for applications with cancer cell imaging or X-ray-computed tomography respectively.

Chemical sensors based on periodic mesoporous organosilica @NaYF4:Ln3+ nanocomposites

“…PMOs are especially interesting, as they show higher loading capacities of hydrophilic and hydrophobic molecules than silica as well as excellent biocompatibility. 23 To the best of our knowledge, this is the first proposed PMO nanocomposites taking advantages of the mesoporous structure of PMOs as well as the excellent luminescence properties of UCNPs. Further, a very simple method was employed in our work compared to the methods regarding coating UCNPs with a silica or PMO shell.…”

Sol-Gel Chemistry: From Molecule to Functional Materials

“…In the last decade, functional nanoparticles designed for imaging and therapeutic applications were of great interest for nanomedicine domain and remain a great challenge [14][15][16][17]. The work presented by Charnay et al is part of this exiting research [18]. For this study, the authors described the preparation of two different upconverting-based hybrid nanoparticles by hydrolysis and polycondensation of bis(triethoxysilyl)ethylene and bis(triethoxysilyl)ethane in the presence of cetyltrimethylammonium bromide (CTAB) as the templating agent.…”