Molecular Envelope Technology (MET) nanoparticles are engineered from biocompatible polymers. By tailoring a number of key properties such as molecular weight hydrophilic and hydrophobic substituents (top left) a range of biomaterials can be created including vesicles, solid nanoparticles, hydrogels, micelles, etc. (bottom left). MET particles are engineered by creating amphiphilic polymers which can self-assemble into micelles. Hydrophobic drugs can be encapsulated into these micelles with high efficacy and are accommodated in the hydrophobic microdomains (middle panels). The MET nanoparticles are stable and small (~50 nm) (top right). Molecular dynamics simulations demonstrate that the material is encapsulated in a very dynamic fashion which facilitates drug release in across barriers (bottom right).