The structure and function of ribonuclease A upon interacting with carbon nanotubes

Ribonucleic acid (RNA) is an important genetic material whose lifetime is most often determined by the rate of its enzymatic degradation. Our studies showed that multi-walled carbon nanotubes and single-walled carbon nanotubes functionalized with carboxylic groups interacted with ribonuclease A (RNase A) and caused the reduction of its activity by changing its conformation, thus protecting RNA from enzymatic cleavage. The results showed that RNase A was less active on the carbon nanotube surface than in free solution, and the activity was decreased further on larger carbon nanotubes, suggesting that carbon nanotubes with various surface modifications may be useful in RNA extraction, purification, and manipulation.