The Cambridge-based team, led by Daniel Kohane, a professor in the Harvard-MIT Division of Health Sciences and Technology, gets around this problem by integrating gold, an excellent conductor. They mixed alginate, a gummy substance often used in tissue scaffolds, and grew gold nanowires throughout it. Then they seeded the alginate with cardiomyoctes from rat embryos, and monitored calcium levels to gauge their electrical conductivity. Compared to a typical scaffold system, the gold nanowire cells' conductivity improved by three orders of magnitude. Kohane said it was "night and day."