Nested Vesicle Reactors Produce Drugs On-Demand
Cell-sized vesicles have enormous potential both as miniaturised pL reaction boats and in bottom-up artificial biology as chassis for artificial cells. In these two areas the debut of light-responsive modules affords enhanced performance, as an instance, to initiate enzymatic reactions from the vesicle inside with spatiotemporal control.
Now, researchers from Imperial College London have made a string of small vesicles that respond to light by dividing their membranes, releasing the substances indoors. The investigators then encased these vesicles at a bigger vesicle that doesn’t respond to light.
This generated a miniature chemical reactor — a container to the smaller vesicles to ensure their published contents could react with one another in a restricted space.
Co-author Professor Oscar Ces, from the Department of Chemistry at Imperial, said: “Our confined microreactors are a crucial step in making responsive artificial cells programmed to carry out certain reactions on cue.
“The science of artificial cells is rapidly advancing to the point where we can mimic biological cell functions with high control and reproducibility, paving the way for targeted drug therapies and embedded biosensors.”
To create the smaller vesicles respond to light, the group engineered their membranes. When ultraviolet light
was shone on them, their lipid membranes responded, creating holes to the contents to escape .The group at Imperial are operating with artificial mobile vesicles to make a ‘toolkit’ of helpful functionalities and structures. These include recent improvements in coupling artificial and biological tissues and sticking artificial cells with each other to form ‘cells’.Chemistry PhD student and first author of the study James Hindley hopes to control increasingly complex reactions using a series of these nested vesicles that react to different wavelengths of light. He said: “The ability to control the timing and location of chemical reactions make these nested vesicles well suited for catalytic applications. It also serves as a foundation for a second generation of nested vesicles that can be used to control multi-step reactions, enabling the production of complex molecules for use in medicine and biotechnology.”
When looking for a way to illustrate their work, the team stumbled on a painting by Wassily Kandinsky that seemed to match perfectly. Co-author Dr Yuval Elani, from the Department of Chemistry at Imperial, said: “The artwork contains circles in a nested arrangement also seen in our vesicle structures. Coloured strobes penetrating through the vesicle from the outside correspond to the UV irradiation used to trigger release in our system.
“Black dashes, streaking through the smaller inner, represent material that is released from the inner vesicles, yet still contained in the larger vesicle microreactor. As we build increasingly complex cell mimics, we can also start to envisage these dashes as communication pathways between different ‘artificial organelles’.”
