Missile tracking

MANY anti-cancer drugs are packaged for delivery into tiny fatty envelopes called liposomes. Because tumour cells are bound more loosely than healthy cells, liposomes squeeze between them more easily. They thus tend to accumulate in cancerous tissue and so, when they degrade, release their payloads there rather than in healthy tissue—to which many of the drugs concerned are equally dangerous.

Such medical missiles can, however, go astray. Even when the same drug in the same sort of packaging is used against the same sort of cancer, the degree to which it strikes its target differs markedly from patient to patient. A way of discovering where the liposomes are going in a particular individual might permit treatments to be tailored to that patient’s needs. And, as they write in ACS Nano, Rafael de Rosales of King’s College, London, and Alberto Gabizon of the Shaare Zedek Medical Centre in Jerusalem, think they have found one.

Many anti-cancer drugs bind readily to metal ions, including those of copper, manganese and zirconium. That interested Dr de Rosales and Dr Gabizon, because these three elements all have radioactive isotopes that release a particle called a positron as part of their decay. Positrons, which are antimatter versions of electrons, are the agents of a body-scanning technique called positron-emission tomography,…Continue reading
Source: Economist