Stealth cover for drug delivery vehicles
13 Apr 2011 by Evoluted New Media
Drug delivery vehicles have been given nanoparticle armour to help it evade the body’s immune system after scientists were inspired by similar shield surrounding some plankton and bacteria
Drug delivery vehicles have been given nanoparticle armour to help it evade the body’s immune system after scientists were inspired by similar shield surrounding some plankton and bacteria
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Four different types of armour added by the University of Warwick researchers |
Chemists at the University of Warwick devised a simple way to give a drug-bearing polymer vesicle its own armoured protection opening a new avenue in the design of vehicles for drug release. The armour gives the vesicle ‘stealth’ capabilities which can help it avoid the body’s defences while releasing the desired drug.
“We took our inspiration from nature, in how it adds protection and mechanical strength in certain classes of cells and organisms,” said lead researcher Stefan Bon. “Organisms that particularly attracted our interest were those with a cell wall composed of an armour of colloidal objects – for instance bacteria coated with S-layer proteins, or phytoplankton, such as the coccolithophorids, which have their own CaCO3-based nano-patterned colloidal armour.”
The researchers gave their chosen colloidal armour particles the opposite charge to that of the polymer vesicles to bind them together and tested their effectiveness using a cryo electron microscope.
They were able to add a highly regular packed layer of microscopic polystyrene balls to the polymer based vehicles; their crystalline-like ordered structure allowed for an additional and precise permeable reinforced barrier for drug release.
They used the same technique to add a gelatine-like polymer – a poly((ethyl acrylare)-co-(methacrylic acid)) hydrogel – to the vesicles. This provided a stealth armour to shield the vesicles from the body’s immune system. It absorbs so much surrounding water into its outer structure that it fools the body into believing it is just water.
