Metal-free thermally-responsive pseudohybrid nanoparticles based on 2-hydroxypropyl-β-cyclodextrin

Pseudohybrid nanoparticles of 800 nm in diameter based on self-assembled high-substituted 2-hydroxypropyl-β-cyclodextrin fabricated in the presence of iron(II) salts were found to be thermally responsive within narrow range of temperature. As-prepared metal-free nanoparticles are stable in aqueous solution at room temperature. However, the increase in temperature results in break-like collapse of nanoparticles to yield species of 400 nm in diameter. On the example of phenolphthalein, it was shown that nanoparticles loaded with model drug decompose to release superficial guest-host inclusion complexes. Local hyperthermia provokes nanoparticles decomposing and drug releasing that allows recognizing focuses of pathology in human body. It might be used for diagnostic medicinal aims and be also considered as basis for the construction of intravascular drug delivery/release systems.