Vesosomes are nested liposomal structures with high potential as advanced drug delivery vehicles, bioreactors and artificial cells. However, to date no method has been reported to prepare ...monodisperse vesosomes of controlled size. Here we report on a multistep microfluidic strategy for hierarchically assembling uniform vesosomes from dewetting of double emulsion templates. The control afforded by our method is illustrated by the formation of concentric, pericentric and multicompartment liposomes. The microfluidic route to vesosomes offers an exceptional platform to build artificial cells as exemplified by the in vitro transcription in “nucleus” liposomes and the mimicry of the architecture of eukaryotic cells. Finally, we show the transport of small molecules across the nucleic envelope via insertion of nanopores into the bilayers.
Monodisperse Uni- and Multicompartment Liposomes Deng, Nan-Nan; Yelleswarapu, Maaruthy; Huck, Wilhelm T. S
Journal of the American Chemical Society,
06/2016, Letnik:
138, Številka:
24
Journal Article
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Liposomes are self-assembled phospholipid vesicles with great potential in fields ranging from targeted drug delivery to artificial cells. The formation of liposomes using microfluidic techniques has ...seen considerable progress, but the liposomes formation process itself has not been studied in great detail. As a result, high throughput, high-yielding routes to monodisperse liposomes with multiple compartments have not been demonstrated. Here, we report on a surfactant-assisted microfluidic route to uniform, single bilayer liposomes, ranging from 25 to 190 μm, and with or without multiple inner compartments. The key of our method is the precise control over the developing interfacial energies of complex W/O/W emulsion systems during liposome formation, which is achieved via an additional surfactant in the outer water phase. The liposomes consist of single bilayers, as demonstrated by nanopore formation experiments and confocal fluorescence microscopy, and they can act as compartments for cell-free gene expression. The microfluidic technique can be expanded to create liposomes with a multitude of coupled compartments, opening routes to networks of multistep microreactors.
Coacervates have been widely studied as model compartments in protocell research. Complex coacervates composed of disordered proteins and RNA have also been shown to play an important role in ...cellular processes. Herein, we report on a microfluidic strategy for constructing monodisperse coacervate droplets encapsulated within uniform unilamellar liposomes. These structures represent a bottom‐up approach to hierarchically structured protocells, as demonstrated by storage and release of DNA from the encapsulated coacervates as well as localized transcription.
Artificial organelles: Monodisperse liposomes containing monodisperse dynamic, functional compartments were achieved using microfluidics and employed as artificial/protocell models to imitate membrane‐less intracellular organelle‐based compartmentalization.
Geometrical cues have been shown to alter gene expression and differentiation on 2D substrates. However, little is known about how geometrical cues affect cell function in 3D. One major reason for ...this lack of understanding is rooted in the difficulties of controlling cell geometry in a complex 3D setting and for long periods of culture. Here, we present a robust method to control cell volume and shape of individual human mesenchymal stem cells (hMSCs) inside 3D microniches with a range of different geometries (e.g., cylinder, triangular prism, cubic, and cuboid). We find that the actin filaments, focal adhesions, nuclear shape, YAP/TAZ localization, cell contractility, nuclear accumulation of histone deacetylase 3, and lineage selection are all sensitive to cell volume. Our 3D microniches enable fundamental studies on the impact of biophysical cues on cell fate, and have potential applications in investigating how multicellular architectures organize within geometrically well-defined 3D spaces.
Microdroplets in microfluidics offer a great number of opportunities in chemical and biological research. They provide a compartment in which species or reactions can be isolated, they are ...monodisperse and therefore suitable for quantitative studies, they offer the possibility to work with extremely small volumes, single cells, or single molecules, and are suitable for high-throughput experiments. The aim of this Review is to show the importance of these features in enabling new experiments in biology and chemistry. The recent advances in device fabrication are highlighted as are the remaining technological challenges. Examples are presented to show how compartmentalization, monodispersity, single-molecule sensitivity, and high throughput have been exploited in experiments that would have been extremely difficult outside the microfluidics platform.
For some decades now, nanotechnology has been touted as the 'next big thing' with potential impact comparable to the steam, electricity or Internet revolutions - but has it lived up to these ...expectations? While advances in top-down nanolithography, now reaching 10-nm resolution, have resulted in devices that are rapidly approaching mass production, attempts to produce nanoscale devices using bottom-up approaches have met with only limited success. We have been inundated with nanoparticles of almost any shape, material and composition, but their societal impact has been far from revolutionary, with growing concerns over their toxicity. Despite nebulous hopes that making hierarchical nanomaterials will lead to new, emergent properties, no breakthrough applications seem imminent. In this Perspective, we argue that the time is ripe to look beyond individual nano-objects and their static assemblies, and instead focus on systems comprising different types of 'nanoparts' interacting and/or communicating with one another to perform desired functions. Such systems are interesting for a variety of reasons: they can act autonomously without external electrical or optical connections, can be dynamic and reconfigurable, and can act as 'nanomachines' by directing the flow of mass, energy or information . In thinking how this systems nanoscience approach could be implemented to design useful - as opposed to toy-model - nanosystems, our choice of applications and our nanoengineering should be inspired by living matter.
Responsive polymer materials can adapt to surrounding environments, regulate transport of ions and molecules, change wettability and adhesion of different species on external stimuli, or convert ...chemical and biochemical signals into optical, electrical, thermal and mechanical signals, and vice versa. These materials are playing an increasingly important part in a diverse range of applications, such as drug delivery, diagnostics, tissue engineering and 'smart' optical systems, as well as biosensors, microelectromechanical systems, coatings and textiles. We review recent advances and challenges in the developments towards applications of stimuli-responsive polymeric materials that are self-assembled from nanostructured building blocks. We also provide a critical outline of emerging developments.
Cell culturing, whether for tissue engineering or cell biology studies, always involves placing cells in a non‐natural environment and no material currently exist that can mimic the entire complexity ...of natural tissues and variety of cell‐matrix interactions that is found in vivo. Here, we review the vast range of hydrogels, composed of natural or synthetic polymers that provide a route to tailored microenvironments.
This review surveys the current developments for hydrogels that are fabricated from natural and synthetic polymers for use as tailored cell culture materials. By focusing on chemical functionalization, physical manipulation, and material properties, this review serves as a guide to select hydrogel materials to answer specific questions in cell biology.
Epigenetic events, which are somatically inherited through cell division, are potential drivers of acquired drug resistance in cancer. The high rate of epigenetic change in tumours generates ...diversity in gene expression patterns that can rapidly evolve through drug selection during treatment, leading to the development of acquired resistance. This will potentially confound stratified chemotherapy decisions that are solely based on mutation biomarkers. Poised epigenetic states in tumour cells may drive multistep epigenetic fixation of gene expression during the acquisition of drug resistance, which has implications for clinical strategies to prevent the emergence of drug resistance.
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