DNA doesn’t just sit still inside our cells — it folds, loops, and rearranges in ways that shape how genes behave.

Studying how single DNA molecules behave helps us to better understand genetic disorders and design better drugs. Until now however, examining DNA molecules one-by-one was a slow process.

Chemical structure of guanine, showing its double-ring purine structure and the functional groups involved in hydrogen bonding with cytosine. (Image: Public Domain) Guanine has the chemical formula ...