Natural and synthetic membrane active molecules increase the permeability of cell membranes. This can help cells combat multidrug efflux pumps as well as improve signaling and transfection. In this work, thermoresponsive metal-organic complexes (MOCs) have been constructed to transport cell impermeable cargo across the membrane through a pore-aiding assembly. These MOCs can be reversibly controlled as they collapse when the temperature is increased and are simultaneously regenerated when the system is cooled down to room temperature. These ON/OFF molecular valves can be potentially used to overcome multidrug resistance (MDR) in cancer cells and as building blocks for artificial cells.
Porous materials with molecular-scale ordering have attracted major attention mainly because of the possibility to engineer their pores for selective applications. Periodic mesoporous organosilica is a class of hybrid materials where self-assembly of the organic linkers provides a crystal-like pore wall. However, unlike metal coordination, specific geometries cannot be predicted because of the competitive and dynamic nature of noncovalent interactions. Herein, we study the influence of competing noncovalent interactions in the pore walls on the biodegradation of organosilica frameworks for drug delivery application. These results support the importance of studying self-assembly patterns in hybrid frameworks to better engineer the next generation of dynamic or "soft" porous materials.
CRISPR/Cas9 is a combined protein (Cas9) and an engineered single guide RNA (sgRNA) genome editing platform that offers revolutionary solutions to genetic diseases. It has, however, a double delivery problem owning to the large protein size and the highly charged RNA component. In this work, we report the first example of CRISPR/Cas9 encapsulated by nanoscale zeolitic imidazole frameworks (ZIFs) with a loading efficiency of 17% and enhanced endosomal escape promoted by the protonated imidazole moieties. The gene editing potential of CRISPR/Cas9 encapsulated by ZIF-8 (CC-ZIFs) is further verified by knocking down the gene expression of green fluorescent protein by 37% over 4 days. The nanoscale CC-ZIFs are biocompatible and easily scaled-up offering excellent loading capacity and controlled codelivery of intact Cas9 protein and sgRNA.
CRISPR-Cas Systems/physiology , Endosomes/metabolism , Gene Editing , Imidazoles/chemistry , Nanoparticles/chemistry , Zeolites/chemistry , Animals , CHO Cells , Cricetulus , Particle Size
AIM: Improving the delivery of siRNA into cancer cells via bubble liposomes. Designing a thermoresponsive pegylated liposome through the introduction of ammonium bicarbonate salt into liposomes so as to control their endosomal escape for gene therapy. METHODS: A sub-200 nm nanovector was fully characterized and examined for cellular uptake, cytotoxicity, endosomal escape and gene silencing. RESULTS: The siRNA-liposomes were internalized into cancer cells within 5 min and then released siRNAs in the cytosol prior to lysosomal degradation upon external temperature elevation. This was confirmed by confocal bioimaging and gene silencing reaching up to 90% and further demonstrated by the protein inhibition of both target genes. CONCLUSION: The thermoresponsiveness of ammonium bicarbonate containing liposomes enabled the rapid endosomal escape of the particles and resulted in an efficient gene silencing.
This work describes the sol-gel syntheses of para-substituted phenylene-bridged periodic mesoporous organosilica (PMO) nanoparticles (NPs) with tunable morphologies ranging from nanowires to nanospheres. The findings show the key role of the addition of organic co-solvents in the aqueous templates on the final morphologies of PMO NPs. Other factors such as the temperature, the stirring speed, and the amount of organic solvents also influence the shape of PMO NPs. The tuning of the shape of the PMO nanomaterials made it possible to study the influence of the particle morphology on the cellular internalization and biocompatibility.
The delivery of large cargos of diameter above 15nm for biomedical applications has proved challenging since it requires biocompatible, stably-loaded, and biodegradable nanomaterials. In this study, we describe the design of biodegradable silica-iron oxide hybrid nanovectors with large mesopores for large protein delivery in cancer cells. The mesopores of the nanomaterials spanned from 20 to 60nm in diameter and post-functionalization allowed the electrostatic immobilization of large proteins (e.g. mTFP-Ferritin, ~534kDa). Half of the content of the nanovectors was based with iron oxide nanophases which allowed the rapid biodegradation of the carrier in fetal bovine serum and a magnetic responsiveness. The nanovectors released large protein cargos in aqueous solution under acidic pH or magnetic stimuli. The delivery of large proteins was then autonomously achieved in cancer cells via the silica-iron oxide nanovectors, which is thus a promising for biomedical applications.
Drug Delivery Systems , Ferric Compounds , Ferritins , Green Fluorescent Proteins , Nanocomposites , Silicon Dioxide , Ferric Compounds/administration & dosage , Ferric Compounds/chemistry , Ferritins/administration & dosage , Ferritins/chemistry , Fluorescent Dyes/administration & dosage , Fluorescent Dyes/chemistry , Green Fluorescent Proteins/administration & dosage , Green Fluorescent Proteins/chemistry , HeLa Cells , Humans , Magnetic Phenomena , Nanocomposites/administration & dosage , Nanocomposites/chemistry , Nanoparticles/administration & dosage , Nanoparticles/chemistry , Porosity , Propylamines/administration & dosage , Propylamines/chemistry , Silicon Dioxide/administration & dosage , Silicon Dioxide/chemistry
Supramolecular self-assembly of histidine-capped-dialkoxy-anthracene (HDA) results in the formation of light-responsive nanostructures. Single-crystal X-ray diffraction analysis of HDA shows two types of hydrogen bonding. The first hydrogen bond is established between the imidazole moieties while the second involves the oxygen atom of one amide group and the hydrogen atom of a second amide group. When protonated in acidic aqueous media, HDA successfully complexes siRNA yielding spherical nanostructures. This biocompatible platform controllably delivers siRNA with high efficacy upon visible-light irradiation leading up to 90 % of gene silencing in live cells.
Anthracenes/chemistry , Gene Transfer Techniques , Histidine/analogs & derivatives , RNA Interference , RNA, Small Interfering/administration & dosage , Crystallography, X-Ray , HeLa Cells , Humans , Hydrogen Bonding , Light , Models, Molecular , Proto-Oncogene Proteins c-bcl-2/genetics , RNA, Small Interfering/genetics
