Preparation and Release Properties of Sol-Gel Encapsulated Proteins

Abstract

A glycoprotein, bovine serum albumin (BSA) was used as a model compound for encapsulation in a sol-gel matrix. Dried gels were ground into powders and meshed to achieve particle sizes less than 250 μm. The products were washed with phosphate buffer. Capillary electrophoresis was used to evaluate the encapsulation efficiency and the kinetic properties of protein release. Several parameters, including the pH and composition of the background electrolyte, were investigated in an effort to eliminate the matrix effect from the determination of release kinetics. Complete separation of the silica matrix from BSA was using phosphate buffer, an applied voltage of 15 kV, and detection at 278 nm. Kinetic studies indicated that most of the BSA was released in the first 5 h. The rate of BSA release gradually decreased, and some BSA after 25 h. These results indicated that dilute potassium phosphate buffer could accelerate protein release, but this was not observed for the concentrations greater than 50 mM. We believe the developed method has potential utility in other systems for in vitro matrix dissolution and drug release studies.

Bio-Doped Microbial Nanosilica as Optosensing Biomaterial for Visual Quantitation of Nitrite in Cured Meats

“…Conventional sol-gel procedures involve extreme pH conditions and high alcohol concentrations, which are destructive to the mechanical stability of the resulting enzymatic biosensor [ 38 ], often leading to leakage of the receptor molecules from the sol–gel-derived silica materials, and thus, the development of a short-term-use biosensor [ 39 ]. For instance, a continuous decrease in enzymatic biosensor response can be perceived for an amperometric glucose biosensor based on silica sol-gel film due to enzyme leaching through the sol-gel matrix over the course of the biosensor stability study for a period of one month [ 40 ].…”

Entrapping quercetin in silica/polyethylene glycol hybrid materials: Chemical characterization and biocompatibility

“…Analogously, the typical aromatic vibrations of the flavonol were differently displaced by about 16-19 cm −1 each (1610 cm − 1 → 1628 cm −1 ; 1560 cm −1 → 1541 cm −1 ; 1458 cm −1 → 1474 cm −1 ). Furthermore, hybrid spectra clearly showed Si\ \O\ \Si and Si\ \OH vibration bands at 1080 and 465 cm − 1 , and 948 cm −1 , respectively [23,[28][29][30][31][32] due to the SiO 2 inorganic matrix.…”

Sol–gel synthesis and thermal behavior of bioactive ferrous citrate–silica hybrid materials

“…4b-f), such as the strong band at 1080 cm -1 with a shoulder at 1200 cm -1 , as well as those at 800 and 465 cm -1 ascribable to asymmetric and symmetric Si-O-Si stretching and bending vibrations [34], respectively. The low-intensity band at 560 cm -1 was attributed to residual 4-membered siloxane rings in the silica network [31,[35][36][37]. Furthermore, the bands in the SiO 2 /Fe(II)C spectra related to Si-OH bond vibrations [38] and O-H stretching [39] appear slightly shifted toward lower wavenumbers compared to those of pure SiO 2 (from 960 to 955 cm -1 and from 3450 to 3425 cm -1 , respectively).…”