CNTs are promising needle-like carriers of both small drug molecules as well as macromolecules such as genes and proteins. CNTs can be functionalized so that certain molecules are attached to their surfaces via covalent or noncovalent bonding. The needle-like shape of the CNTs enables them to perforate cellular membranes and transport the carried therapeutic molecules to the cellular components.
CNTs can be made into artificial blood capillaries. Capillary assisted deposition method of CNT films has application in repairing injured body parts in human beings. Another application of CNTs is in biochemical sensors.
The biodegradation of carbon nanomaterials by microbes and enzymes is of a great importance for reducing their toxicity to living organisms and removing them from the environment.