Nanoparticles with loose grips get drugs to tumors fast

Sometimes, a loose grip is better than a tight one when delivering anti-cancer drugs into a tumor. One key to nanoparticle drug delivery is how to tie the therapeutics to the drug delivery device. Researchers at Case Western Reserve University discovered that using really tight covalent bonds often change the properties of components in the system, resulting in complications. So, the solution was to loosen the grip a bit and use noncovalent bonds.

The release from Case Western uses a good analogy when describing the difference: "In molecule construction, a covalent bond is a heavy rope lashed and knotted; a noncovalent bond is a shoestring tied in a bow."

The scientists used a noncovalent bond to tie an anti-cancer drug to "golden missiles" that rush directly to the tumor. Getting it there quickly and directly enables patients to receive lower doses of the toxic chemicals, saving healthy tissue from damage and other harsh side effects suffered in traditional chemotherapy.

And preliminary tests show an anti-cancer drug loosely attached to gold nanoparticles starts accumulating deep inside tumors within minutes of injection and can be activated for an effective treatment within two hours. The same drug injected alone takes two days to gather and attacks the tumor from the surface - a far less effective route.

- take a look at the Case Western release
- and the abstract in the Journal of the American Chemical Society