The pathogenic free-living amoeba, Acanthamoeba castellanii, is responsible for a rare but deadly
central nervous system infection, granulomatous amoebic
encephalitis and a blinding
eye disease called
Acanthamoeba keratitis. Currently, a combination of
biguanides, amidine,
azoles and
antibiotics are used to manage these
infections; however, the host cell cytotoxicity of these drugs remains a challenge. Furthermore, Acanthamoeba species are capable of transforming to the
cyst form to resist
chemotherapy. Herein, we have developed a
nano drug delivery system based on iron oxide nanoparticles conjugated with
isoniazid, which were further loaded with
amphotericin B (ISO-NPs-
AMP) to cause potent antiamoebic effects against Acanthamoeba castellanii. The IC50 of
isoniazid conjugated with magnetic nanoparticles and loaded with
amphotericin B was found to be 45 μg/mL against Acanthamoeba castellanii trophozoites and 50 μg/mL against
cysts. The results obtained in this study have promising implications in drug discovery as these nanomaterials exhibited high trophicidal and cysticidal effects, as well as limited cytotoxicity against rat and human cells.