#microfluidic device

Mother’s Touch

Fragile but full of life, an early embryo must embed in the womb or perish. Attempts to watch the vital process of implantation are often obscured by layers of tissue – but here scientists have found another way. Keeping a mouse embryo alive in nourishing hydrogel inside a microfluidic device, they use live cell imaging to watch as the embryonic cells (highlighted in green) grow arm-like trophoblast giant cells, reaching out for the lining of endothelial cells, similar to those found along the womb’s blood vessels. As the trophoblast makes contact, researchers find the embryo switches on genes to adapt to its new home, connecting up with the blood vessels and finding protection in the soft layers. This living model for implantation may now be used to study the crucial steps in early pregnancy, perhaps revealing ways to guide the process in humans and avoid early miscarriage.

Written by John Ankers

Video from work by Niraimathi Govindasamy and colleagues

Embryonic Self-Organization research group, Max Planck Institute for Molecular Biomedicine, Münster, Germany

Video copyright Elsevier 2021. Reproduced with permission.

Published in Developmental Cell, November 2021

Captivating Capsules

Many medications are packaged in capsules that slowly dissolve after being swallowed, gradually releasing their contents into the body in a controlled manner. Shrinking that idea down to a microscopic scale, these tiny capsules are less than half a millimetre across and are made from layers of biodegradable polymers designed to slowly break down over days or even months, depending on the thickness of the capsule walls. Originally developed as a way of delivering vaccines more effectively, the researchers behind the micro-capsules are now investigating whether cancer treatments such as combinations of chemotherapy drugs, immunotherapy or gene therapy can be trapped inside the tiny blocks. In this image, the capsules have been filled with red dye in order to see how well they work and measure the speed at which they release their cargo. Other applications for these clever capsules include using them as environmental sensors or miniature microfluidic devices.

Written by Kat Arney

Calling the Shots: A Flexible Platform for All-in-One Delivery. A winner in the 2020 Koch Institute Image Awards

Image by Morteza Sarmadi, Christina Ta, Robert Langer and Ana Jaklenec; Langer Laboratory, MIT

Image courtesy of the Koch Institute Image Awards

Dash of Lyme

A bite from a stealthy tick often carries these spiral-shaped Borrelia burgdorferi bacteria (highlighted in red and green) into the blood stream causing Lyme disease. Infection brings a confusing range of symptoms, from muscular pain to a rash that moves outwards from the bite. Common laboratory tests on blood serum can miss these early stages, slowing down treatment and recovery. But help may come with a newly-discovered set of biomarkers – biological molecules that act like a fingerprint for the disease in chemical tests. Performing sensitive tests in a sort of portable microfluidic laboratory, may allow quick diagnosis of the early stages of Lyme disease, halting Borrelia burgdorferi in their spiralling tracks.

Written by John Ankers

Image from the NIH National Institute of Allergy and Infectious Diseases

Research from Department of Biomedical Engineering, Columbia University, New York, NY and Immuno Technologies Inc, Memphis, TN, USA

Image copyright held by NIAID

Research published in the Journal of Clinical Microbiology, October 2019

Crowd Surfing

Our cells are crammed with life – jostling crowds of macromolecules, like these proteins and lipids vying for space in a computer model of a bacterial cell. With each having a purpose and a place to be, the situation looks chaotic, but new experiments suggest crowding actually helps certain particles travel faster. Researchers piped molecules of different sizes and textures into a microfluidic device designed to mimic real-life microscopic crowds. They discovered that squishy ones, more closely resembling particles in found living cells, squeeze between 'crowder' molecules, moving from crowded areas to where there's space. Such concentration gradients are essential to help traffic into and out from cells, and now it seems inside them too. The next step is to find ways to control crowds inside cells, revealing new ways to guide the flow of macromolecules in health and disease.

Written by John Ankers

Image by Adrian H Elcock

Research from Departments of Chemistry and Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania, PA, USA

Image originally published under a Creative Commons Licence (CC BY 2.0)

Research published in ACS Nano, July 2019

Jet Lab

Beyond test tubes, petri dishes and pipettes, modern laboratory tests are often performed inside tiny networks of tubes that would fit on credit cards – ‘labs on chips’ controlled by computer to mix chemicals and cells together. Here though, rather than forcing fragile cells through tiny pipes, chemicals are blown into arc-like shapes by tiny jets of air; part of a new technology called open microfluidics. Angling the jets creates different patterns of fluids, or perhaps cells, suited to helping reactions along. Mathematical modelling simulates the overall effect (upper part of each shape), before scientists create the real experimental set up (underneath). As the models explore even more complicated plans, they aim to discover the best designs for certain tasks, like mixing drugs or performing quicker tests on patients’ samples.

Written by John Ankers

Image adapted from work by Pierre-Alexandre Goyette and Étienne Boulais, and colleagues

École Polytechnique de Montréal, Montréal, QC, Canada

Image originally published under a Creative Commons Licence (BY 4.0)

Published in Nature Communications, April 2019

Junction Box

Millions of times a day we turn our thoughts into actions - at neuromuscular junctions where electrical signals from motor neurons feed into our muscles. Amyotrophic lateral sclerosis (ALS) gradually weakens these connections for thousands of people around the world – but here’s a vital step towards new treatments. Inside a sort of lab-in-a-box called a microfluidic device, a bundle of nerve cells (artificially-coloured green with nuclei in blue) is reaching out tiny finger-like neurites towards muscle cells (purple) – creating a living 3D model of a neuromuscular junction. The neurons are modified to be optogenetic – they respond to pulses of laser light by pulling at the muscle cells, revealing weaker forces in cells grown from ALS sufferers. The next job is to bathe the diseased cells in different combinations of drugs, looking for clues to restoring neuromuscular junctions to full strength, in the hope of treating ALS as well as other conditions affecting the nervous system.

Written by John Ankers

Image by Tatsuya Osaki, Massachusetts Institute of Technology

Department of Mechanical Engineering, Massachusetts Institute of Technology (MIT) , Cambridge, MA, USA

Image copyright held by the original authors

Research published in Science Advances, October 2018

Offending Defenders

A stage of battle 30,000 times smaller than a roman amphitheatre, this microfluidic device recreates the microscopic events of Alzheimer’s disease. Ageing brains often build up waste proteins – gunky amyloid plaques and tangled tau proteins. Although these can interfere with signals between brain cells like those seen here (highlighted in green), they may also build up harmlessly for decades. The real problem is how the brain responds – microglial cells (red), part of the brain’s own immune defences, flood towards affected areas of the brain (or down the spindly channels here) and attack the struggling neurons. While the overzealous defenders attempt to get rid of the plaques, levels of neuroinflammation rise, causing irreparable damage. This lab-grown model can now be put to use in finding new ways to stop plaques from forming in the first place, but also testing drugs designed to calm the microglial cells of those at risk.

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Written by John Ankers

Image from work by Joseph Park and colleagues

University of North Carolina at Charlotte, NC, USA

Image copyright held by the original authors

Research published in Nature Neuroscience, June 2018