Preparation and In Vitro Cytotoxicity Assessments of Spherical Silica-Encapsulated Liposome Particles for Highly Efficient Drug Carriers

Abstract

This work reports the formation of spherical solid silica-encapsulated liposome particles (SLPs) as functions of the concentration of silica precursor, reaction time, temperature, and volume ratios of solvent, respectively. The solid SLPs are more robust and have better drug-loading-efficiency liquid liposomes in carrier formulations. The liquid-state liposomes are hard to handle and have a lower drug-loading efficiency because they are fragile to external stimuli and have narrow hydrophobic phospholipid bilayers. The SLPs were obtained by silicification with tetraethyl orthosilicate (TEOS) in the hydrophilic region of phospholipid bilayers by a sol−gel process. These SLPs were characterized by scanning electron microscopy (SEM), focused ion beam (FIB)-SEM, confocal laser scanning microscopy (CLSM), thermogravimetric analysis (TGA), ζ-potential, X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, and UV−vis spectroscopy. The obtained SLPs were spherical with an average size of 2−3 μm. The hydrophilic region of the SLP phospholipid bilayers was confirmed using CLSM with green fluorescent fluorescein isothiocyanate (FITC) labeling and FIB-SEM. Furthermore, the drug-loading capacity and in vitro cytotoxicity assessments were performed using several drug compounds and L929 cells. The drug-loading capacity of the SLPs was >95%, and in particular, the hydrophobic drug-loading capacity was 2.3 times higher than that of general liposomes. Moreover, the result of an in vitro cytotoxicity assessment of the SLPs was good, about 99% of cell viability.

Osteogenic effect of magnesium oxychloride cement modified with phytic acid and loaded with strontium ranelate

“…Compared with the blank control group, MOC, 1.25 wt% PA-MOC and 1 wt% SrR/1.25 wt% PA-MOC cells were all more than 70% active. Indicating that the extract of the sample was not cytotoxic to BMSCs (according to ISO 10993-5, cell viability results of 70% or more were considered to be non-cytotoxic [ 24 ]), the sample had good biocompatibility. Compared with MOC and 1.25 wt% PA-MOC, the cell activity value of 1 wt% SrR/1.25 wt% PA-MOC sample group was higher, indicating that the loading of SrR could promote cell proliferation, which may be related to the Sr 2+ contained in SrR.…”

Review on sterilization techniques, and the application potential of phage lyase and lyase immobilization in fighting drug-resistant bacteria

“…Its high surface area and porous structure provide it with superior adsorption properties, and the presence of many hydroxyl groups on its surface promotes enzyme adhesion. 132,133 Moreover, silica can be used in many different forms, such as colloidal silica particles, silica gel matrix, and fumed silica. For instance, immobilized lipase with a functionalized mesoporous SiO 2 retained 96% of the free enzyme activity.…”

Overcoming the Low-Stability Bottleneck in the Clinical Translation of Liposomal Pressurized Metered-Dose Inhalers: A Shell Stabilization Strategy Inspired by Biomineralization

“…The mechanical properties of silica shells can be controlled using different silica precursors with varying chemical structures. For instance, triethoxyvinylsilane (TEVS) [ 141 , 142 ] can be used for a soft shell, while Tetraethoxysilane (TEOS) [ 143 ] can be used for a hard one. The deposition of silica on the surfaces of liposomes is structure-dependent on the silanization condition [ 144 ] and influenced by the reaction conditions.…”

“…The deposition of silica on the surfaces of liposomes is structure-dependent on the silanization condition [ 144 ] and influenced by the reaction conditions. Chang et al [ 142 ] used TEOS through a sol–gel silicide to endow the liposome with a silicon shell ( Figure 6 A). This work reported that the formation of solid silica encapsulated liposomes (SLPs) was related to the TEOS concentration, reaction time, temperature, and solvent volume ratio.…”

“… ( A ) Schematic representations of silica encapsulation in a liquid liposome and FIB-SEM images of SLPs. Reproduced from [ 142 ]. Copyright: 2021, American Chemical Society.…”