Covalent diphenylalanine peptide nanotube conjugated to folic acid/magnetic nanoparticles for anti-cancer drug delivery

Micro and nanotubes obtained from the self-assembly of diphenylalanine peptides (FNTs) were conjugated to folic acid/magnetic nanoparticles (FA/MNPs) and evaluated as a potential system for anti-cancer drug delivery. The conjugates were obtained by providing a covalent linkage through the amine groups on FNTs with the carboxylic groups on FA/MNPs. The anti-cancer therapeutic 5-fluorouracil (5-FU), and anti-inflammatory cargo flufenamic acid (FFA), were loaded in peptide arrays during their self-assembly in the liquid phase. AFM and CLSM analysis indicated the presence of FA aggregates on FNTs. The data revealed that the cargo 5-FU, was distributed in dendrite peptide nanotubes whereas the non-polar cargo FFA, was homogeneously embedded in the structure of large discrete micro tubes. FTIR spectra of FA-MNPs/FNTs showed peak of amide II at 1623 cm−1 indicating covalent interactions between amines and carboxylic groups and confirmed the successful conjugation of the nanoparticles and peptide assemblies. The results indicated that 5-FU has been released from FNTs within 4 h, and incorporation of 5-FU in FNTs hydrogels has significantly slowed the release rate within the first 2 h. Our approach offers a new pathway for cancer treatment in which several functionalities are embedded in a single carrier.

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