Peptidomimetic–functionalized carbon nanotubes with antitrypsin activity

Water-soluble functionalized carbon nanotubes (CNTs) have been prepared and further conjugated through a stable covalent bond with two peptidomimetics. The structural design of the covalently grafted peptidomimetics to the CNTs is based on their structural similarity with the metabolites of antagonist G of substance P. A variety of analytical spectroscopic methods, in combination with electron microscopy and thermal analysis, aided the structural and morphological characterization of the four newly synthesized peptidomimetic–CNT conjugates. It is demonstrated that the trypsin inhibitory effect of the peptidomimetic–CNT is enhanced as a result of the high-loading of peptidomimetics onto the skeleton of the modified water-soluble CNTs. Additionally, the peptidomimetic–functionalized CNT conjugates can be recovered and re-employed up to six biological evaluation cycles showing the same trypsin inhibitory activity. Such a nanosized system is extremely advantageous for the inhibition of inflammation or malignancy and could find potential future biological applications in the area of drug delivery systems.