Fabrication and biocompatibility assessment of polypyrrole/cobalt(II) metal-organic frameworks nanocomposites

Abstract

Nowadays, metal-organic frameworks (MOFs) have emerged as promising tools for different biological applications and therefore, efforts are ongoing to develop more biocompatible MOFs-based nanocomposites. We aimedto fabricate some new conductive nanocomposites of polypyrrole and cobalt-MOF with different weight percentages(PPy/x%Co-MOF) using the solution mixing method and characterize them through FT-IR (Fourier-transform infrared),PXRD (powder X-ray diffraction), SEM (scanning electron microscope), and TEM (transmission electron microscope)techniques. The biocompatibility of nanocomposites was assessed by haemolytic, cytotoxic, and quantitative reversetranscription PCR (qRT-PCR) assays. FT-IR and PXRD results revealed that nanocomposites consisted of pure MOFsand PPy. Moreover, SEM results indicated their spherical morphology along with an average diameter of 190 nm.(3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed a concentration, and percentagedependent cytotoxic effect of the nanocomposites on some cell lines including 3T3 fibroblasts, MCF-7, and J774.A1macrophages. Haematological toxicity of PPy/x%Co-MOF composites was less than 7% in most concentrations. Furthermore, PPy/x%Co-MOF composites did not show any significant effect on the expression of cyclooxygenase−2(COX-2)and inducible nitric oxide synthase(iNOS) genes. In sum, regarding the haemolytic, proinflammatory, and cytotoxictests, prepared nanocomposite demonstrated the reasonable in vitro biocompatibility which may be considered as ahopeful platform for further investigations including clinical applications.