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Silica Nanoparticles for Drug Delivery
Published in Vladimir Torchilin, Handbook of Materials for Nanomedicine, 2020
Ross and co-workers used MCM-48, which has a cubic pore structure, coated with succinylated ε-polylysine for the colon specific release of prednisolone. At the relatively acidic pH values in the stomach and small intestine (1.9 and 5.0, respectively), the polymer covers the pore entrances. Ionization of the polylysine at pH 7.4, similar to what is observed in the colon, leads to expansion of the polymer matrix and thus drug release. Carrier toxicity was evaluated in RAW 264.7 macrophages as well as LS 174T and Caco-2 adenocarcinoma intestinal epithelial cells and the particles were found to be biocompatible up to 100 μg mL−1. Using the cell membrane impermeable dye sulforhodamine B, it was found that the polymer-coated particles were successfully internalized into all three cell lines through active transport [49].
Design of artificial cells: artificial biochemical systems, their thermodynamics and kinetics properties
Published in Egyptian Journal of Basic and Applied Sciences, 2022
Adamu Yunusa Ugya, Lin Pohan, Qifeng Wang, Kamel Meguellati
Therefore, the minimal representations of synthetic cellularity using biological processes generated by bottom-up strategies are generating a growing interest in the field of synthetic biology. The use and development of in vitro gene expression systems (IVGES) is considered an advance in photocell engineering to provide off-line biological content for storage and processing in synthetic cell-free environments. Tang group used carboxymethyl-dextran/polylysine (CM-dextran/PLys) coacervate for the sequestration and retention of a plasmid-containing IVGES to show cell-free gene expression and folding of the red fluorescent protein mCherry at pH = 8 [30]. Another study on engineered cells in mammalian tissues is linked to a synthetic module (photoactivated synthesis of cyclic dimeric GMP) to obtain a 40-fold photoactivation of gene expression [36] (Figure 3). Recently, it was found that the oxygenation of stem cells is stimulated by artificial membrane-binding proteins during the engineering of large cartilage tissues [37]. It was reported in 1997 that the vesicle growth was driven by the simple dipeptide catalyst seryl-histidine (Ser-His) through the catalytic synthesis of a hydrophobic dipeptide, N-acteyl-L-phenylalanine-leucinamide (AcPheLeuNH2) [38].