Biocompatibility and toxicity of novel iron chelator Starch-Deferoxamine (S-DFO) compared to zinc oxide nanoparticles to zebrafish embryo: An oxidative stress based apoptosis, physicochemical and neurological study profile

Objectives: Clinically approved iron chelators are effective in decreasing significant transfusional iron accumulation. Starch-Deferoxamine (S-DFO), a novel high molecular weight iron chelator, was produced to increase binding capacity to iron and reduce toxicity. Although its efficacy was established in one small cohort clinical trial, its potential adverse effect was not adequately addressed. Methods: We utilized zebrafish model to assess S-DFO toxicity using following assays: mortality, teratogenicity, hatching rate, tail flicking, Acridine Orange staining for apoptosis detection, o-dianisidine staining for hemoglobin synthesis, and the level of Hsp70 as a general stress indicator. Embryos were exposed to different concentrations of S-DFO, Zinc Oxide nanoparticle (ZnO) (positive control), along with untreated control (UC). Results: S-DFO showed no significant mortality nor deformities at all tested concentrations (0.0-1000 pM). Thus, the LC50 is expected to > 1000 pM. 100 pM S-DFO treatment did not affect embryo development (as judged by hatching rate); neuromuscular activity (as judged by tail flicking); and hemoglobin synthesis. Neither apoptosis, nor increase in Hsp70 level was noticed upon S-DFO treatment. Conclusion: Our assays demonstrate that S-DFO does not induce cellular or biochemical stress and has no adverse effect on organ development of zebrafish embryos, suggesting its safe use as an iron chelator.