Director, Artificial Cells and Organs Research Centre, McGill U., Montréal.
Thomas Chang was born in Swatow, a coastal town in southern China. His grandfather was a general practitioner who rode a bicycle to tend to farmers in the outlying villages. Years later, Chang, while still an undergraduate at McGill, invented the world's first artificial cell in 1957. His idea was to make tiny, ultrathin plastic microcapsules that could hold biological agents (such as enzymes). If he could control the permeability of the plastic membrane, he could control what passed through the wall of his artificial cell, and thus mimic many of the functions of real cells. The idea was first developed by primitive experiments in his residence room. He bought a perfume atomizer and some cellulose nitrate (collodion) from a drugstore to form the plastic membrane, and obtained haemoglobin particles from a laboratory. He spent a few weeks spraying different combinations of plastic and haemoglobin onto a plate on the floor, until he succeeded in encapsulating some of the haemoglobin within the plastic to form tiny artificial cells, one millimetre in size. Although more amused than impressed by his idea, Chang's superiors allowed him a small corner in a teaching lab to continue his work. By the end of that summer, spent struggling to pay his bills and continue his project, Chang succeeded in demonstrating the validity of the principle of artificial cells. After earning his PhD in physiology, Chang developed the first artificial blood and a new cellular-based approach to an artificial kidney, liver and pancreas. While various drawbacks persist, Chang's inventions have proved useful as temporary measures and in conjunction with other approaches. The artificial-cell kidney, for example, is faster, much cheaper and more easily portable than traditional dialysis, despite its inefficiency in absorbing ammonia. Another persistent problem is research funding, perhaps because of competition with existing technologies. Chang is a recipient of the Order of Canada.
Sources: "The Bionic Threshold" by Sylvia Wright, Equinox, c. 1990;
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