Nanofibres Deliver Drug To Exact Spot

摘要

Stringing drug molecules into fibres that unravel in the presence of a specific enzyme could allow medication to be released exactly when and where it is needed.rnPreviously, drugs have been bundled with polymers that, once injected into a patient, slowly break down to release the drug. By tuning the properties of the polymer, this allows the timing of a drug's release to be pre-programmed. However, the polymers can release toxic molecules as they degrade.rnNow George John from the City University of New York and team have created a way to pre-program drug release without using potentially harmful polymers. In John's system, drugs are released in response to a specific enzyme, allowing where and when the release occurs to be controlled.rnThe team attached a "water-hating" fatty acid to the end ofrna "water-loving" drug molecule -in this case the painkiller paracetamol (acetaminophen). Because the water-hating fatty acid tails are attracted to each other, and the water-loving paracetamol heads to other heads, the molecules stack,rnwith the tails at the centre and the heads facing outwards, to form nanofibres that cluster together in a mesh (see Diagram).