Rely on research | The University of Chicago Magazine
At first glance, you may see a serene lake at sunset or delicate petals on a tree blooming in winter. But take a closer look at the UChicago chemistry professor Boji Tianand you may notice that these images don’t quite capture the world as it is. They merge scenes from nature with hints of technology, just as his research merges biological and synthetic systems.
A materials scientist who works with semiconductors for biomedical applications, Tian designs devices to stimulate or modulate parts of the anatomy, such as the heart and neurons. One project his lab has been working on for nearly eight years is a solar-powered pacemaker. The team is also exploring technology to influence microbes, including an edible material that could modulate the gut microbiome, potentially helping to treat gastrointestinal conditions like inflammatory bowel disease.
Tian’s research is inspired by the natural world: its shapes, textures and patterns. And this influence is spreading his works of art, often created in collaboration with his science: a river landscape with a forest of nanowires, a neural cell framed like a snowy mountain. These are created digitally, but Tian has been painting and drawing since childhood.
Encouraged by his father, Tian started practicing calligraphy when he was three years old. He started painting at the age of six and began to experiment with drawing software at the age of 15 or 16, when his father bought him his first computer. (At that time he was falling in love with chemistry and devoting more attention to science.) He still enjoys doing analog art but finds it time consuming.
At Fudan University in Shanghai, where Tian earned a bachelor’s and master’s degree in chemistry, his dedication to art and science began to merge. He joined a research laboratory that designed and synthesized porous, ordered and geometrically structured materials with nanoscale pore size. Such structures exist in nature but not at the same scale, Tian says. 2D and 3D montages fascinate him. It’s basically a work of art, he thought.
Scientists and artists need to be innovative and imaginative, Tian says, inspired by how they recreate their view of the world. This multidimensional creativity is particularly evident in one of his lab’s new research directions, what he calls “synthetic reality.” The team is focused on designing tissue-like materials, but not in the traditional sense of tissue engineering (such as growing artificial organs or materials for direct medical use). “We think more broadly,” he says.
Imagine incorporating organic tissue into your environment – an idea that struck Tian during a recent visit to the intensive care unit at Comer Children’s Hospital to meet with a collaborator. There, it occurred to him that premature babies have physical and emotional needs that would have been met by their mother’s body, but they are processed inside what is essentially a stick-lined box. Maybe the team could create an environment like a womb. “We don’t really need reality, as long as it feels like reality,” he says. “That should be enough.” Similarly, some stringed instruments traditionally use gut strings, made from animal intestines, which produce a sound that is warmer than steel. But a gut-like synthetic fabric could produce an equally beautiful sound. Reality: inspired by nature, but made in the laboratory.
Tian thinks the combination of science and design is good business – she sells innovation through communication. “It helps motivate people,” he says, “brings us together through storytelling.” But he admits that creating art is also a kind of compromise. He finds illustration relaxing but sometimes feels guilty for neglecting his research. That way he doesn’t have to choose.
To depict the interfaces where electronics and cells integrate seamlessly, Tian created this composite image, overlaying a photograph of a flexible bioelectronic device on a Chicago harbor. Shown in the lower half of the image, the device is itself a composite: a rolled-up sheet of artificial vascular tissue embedded with threads that may one day be able to measure proteins or other chemicals in the blood . Tian used vertical elements – the foreground electrode grids and the background masts – to “imply an upward progression of the field of bioelectronics”. Always sensitive to color, Tian chose warm hues “to give a feeling of harmony and positivity”, noting that a port is a place of safety and comfort. “While the background and foreground show very distinct objects,” Tian explains, their juxtaposition exhibits a shared spirituality.
The opalescent swirls on silicon membranes, as seen here under a light microscope, are not created by dyes or pigments. The color comes from a process called spot etching, which eats away at the surface of the silicon, leaving holes that scatter light, creating colored “spots.” But the process does more than create psychedelic patterns: it creates a nanoporous material that functions like a solar cell. Normally, solar cells need at least two layers of different materials to work, but Tian’s single-layer method creates soft, flexible, and extremely small solar cells that can be used inside the body. A tiny optical fiber carries light from outside to power them. “It’s transformative because without the engraving, the material is almost useless,” says Tian. But after a simple burning process, it can turn light into electricity and help a heart keep pace.
Highlighting recent breakthroughs in neural sensing and modulation, and the potential of biomaterials to treat neurological disorders, Tian illustrated a plum blossom tree. Its branches are neuronal dendrites – tree-like protrusions that carry signals from other neurons – as seen under a light microscope. Tian invoked elements of traditional Chinese painting: diffuse outlines, a black and dark red color scheme, and a red seal in the corner. National flower of China, the plum blossom has a special meaning. The plant, which blooms in winter, means perseverance. “That’s the key message I want to highlight for this image. It’s a tough field,” says Tian, who is the only faculty member working in bioelectronic stimulation interfaces at the University of Chicago. “We need perseverance to succeed.”
Semiconductor nanowires have played an important role in Tian’s research since graduate school. In this landscape, each element represents a cellular or nanowire feature and “tells you how the whole field of nanowire bioelectronics has evolved,” he says. Mountains are cells; the river is the extracellular matrix (a network of proteins and other molecules between cells); the bridge is an intercellular nanotube (a conduit between cells); the sun is an extracellular vesicle (a globule surrounded by a membrane that facilitates cellular communication). In the distance, the green trees represent early research, which focused primarily on straight threads. Downstream, branching bushes and zigzag logs indicate novel nanowire geometries. The wire bent at about 60 degrees on the face of the mountain represents a device that records information inside a cell – part of Tian’s doctoral research.
Tian’s lab creates 3D nanostructures using a classic printing technique: lithography. Using atomic gold as a lithographic mask, the team chemically etches silicon into complex shapes. Tian constructed this 3D reconstruction using a series of electron microscope images. The image only shows the surface of a skeleton-like silicone object, part of a material designed to adhere tightly to tissue. The colors highlight the difference in curvature: the blue parts curve outward while the gold dips inward. The original version used blue and red – a typical color palette for science – but Tian’s choice to replace red with gold points to his humanistic impressions. “That etching, that etching, seems like a very painful process for a material,” he says. This creates losses, but it is also part of growing and reaching maturity. The engraving process, for him, lets inner strength shine through.
Imagine a snow-capped mountain top with a gondola cable straddling the top, but on a nanoscale. This scanning electron microscope image that accompanied a paper published in the winter of 2018 shows a neuron with a silicon nanowire, which functions like a solar cell, perched on top. When Tian shines a light on the wire, it converts the photons into electrical energy, stimulating — or exciting — the neuron. This technology can turn neurons on or off and could help treat neurological brain conditions or restore vision to a damaged retina, for example. Most neural activation methods are either mechanically invasive or require genetic manipulation of target cells. Like the neurons they were studying, “we were extremely excited,” Tian says, to see the device working.