Mesoporous superparamagnetic cobalt ferrite nanoclusters: Synthesis, characterization and application in drug delivery

•L-Arginine coated CoFe2O4 nanoclusters with mesoporous structure.•The nanoclusters exhibited superparamagnetic behavior and negligible cytotoxicity.•High drug loading capacity and pH-responsive release behavior. In this contribution, an amino acid of L-Arginine coated cobalt ferrite (CoFe2O4) nanoclusters with mesoporous structure were synthesized via a facile solvothermal strategy. The morphology, structure and properties of bare CoFe2O4 and L-Arg-coated CoFe2O4 nanoclusters were characterized in detail by SEM, TEM, XRD, XPS, TGA, BET and SQUID. It was found that these products exhibited a well-defined clusters-like morphology and a uniform size distribution with an average diameter of 103.6 nm. The as-prepared superparamagnetic CoFe2O4 nanoclusters with mesoporous structure and negligible cytotoxicity could be utilized as an effective drug delivery for doxorubicin hydrochloride (DOX). The drug loading capacity and the release behavior in vitro of DOX from L-Arg-coated CoFe2O4 nanoclusters at different pH values (4.0 and 7.4) were investigated. The results showed that the developed drug delivery system exhibited a high drug loading capacity and a pH-sensitive drug release behavior.