Aqueous-Based Silica Nanoparticles as Carriers for Catalytically Active Biomacromolecules

Abstract

Silica nanoparticles have emerged as excellent hosting matrices for the immobilization of biomacromolecules due to good biocompatibility, chemical stability, low toxicity, and facile controllability. However, most of the traditional synthesis protocols for silica nanoparticles are based on hydrolysis and condensation of alkoxysilane in aqueous alcohol solutions in the presence of ammonia as a catalyst. Such conditions are too harsh for encapsulation of certain biomacromolecules. Herein, a one-step method for the synthesis of silica nanoparticles with encapsulated biomacromolecules in an aqueous solution without alcohol and catalyst is proposed. To demonstrate the feasibility of this strategy, six different kinds of biomacromolecules were encapsulated in the silica nanoparticles as model systems. The biomacromolecules encapsulated in the silica nanoparticles still preserved high bioactivity. The composites showed an excellent reusability and a good protective effect against various extreme environments. This study demonstrates how silica nanoparticles can be prepared for biomacromolecule immobilization without any alcohol and catalyst and thus offers improved encapsulation.

Enzyme Encapsulation by Facile Self-Assembly Silica-Modified Magnetic Nanoparticles for Glucose Monitoring in Urine

“…Silica nanoparticles can be obtained by a self-condensation method under mild conditions, which has been proved by our previous work [25]. The method is more benign since no organic solvents and catalytic agents participate in the polymerization.…”

“…Although some biomacromolecules could be encapsulated into a silica matrix successfully, some problems still need to be overcome, such as the difficulty of encapsulation and the insurmountable escape of negatively charged proteins from the silica matrix [23,24]. Another approach, proposed by our group, is a one-step self-assembly process in which biomacromolecules could be encapsulated in silica nanoparticles without any organic solvent and the catalyzer of acid or base [25]. The biomacromolecules can retain their entire structure and biological activity in the production process.…”

The heat-promoted metal–support interaction of a PtCu/SiO2 carbon-free catalyst for the methanol oxidation and oxygen reduction reactions

“…The peaks at 1100 cm −1 represent the anti-symmetric stretching vibration of Si-O-Si. 23 The peaks at 1633 cm −1 represent the bending or deformation mode of molecularly coordinated water and the peaks at 3424 cm −1 represent the stretching vibration of O-H that were part of the water molecule and Si-OH. 24 These peaks were also observed on the other as-prepared catalysts (Fig.…”

Aptamer-functionalized two-photon SiO2@GQDs hybrid-based signal amplification strategy for targeted cancer imaging

“…32 In these strategies, silica nanoparticles (SiO 2 NPs) usually act as a matrix of nanosensors for the in situ synthesis of fluorescent composite nanoprobes, due to the possibility of tuning their size and non-toxicity, and functionalizing their surface. 33,34 However, problems found are that these siliconsphere-based nanoprobes are not uniform and have a low fluorescence quantum yield, which limit their potential application due to the lack of real-time and high-sensitivity imaging. In addition, the combination of a nanomaterial-based signal amplification strategy with TPA imaging appears to be rare.…”