RESUMEN
In this study, we investigated the mechanisms involved in multi-wall carbon particles/nanomaterials (MWCNM) induced cytotoxicity using human embryonic kidney (HEK293) cells and to assess the effect of physicochemical properties on the cytotoxicity and oxidative stress induced by the carbon nanomaterials (CNM). To elucidate the possible mechanisms of CNM-induced cytotoxicity, cell viability (3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide [MTT assay]), cell membrane damage (lactate dehydrogenase enzyme [LDH] assay), reduced glutathione (GSH), interleukin-8 (IL-8) and lipid peroxidation levels were quantitatively assessed under carbon nanomaterials exposed (48 h) conditions. Exposure of different sizes of four CNM at dosage levels between 3 and 300 µg/mL decreased cell viability in a concentration- and size-dependent manner. Exposure of CNM (10-100 µg/mL) to HEK cells resulted in size-, surface area- and concentration-dependent cell membrane damage, increased production of IL-8, increased thiobarbituric acid reactive substances (TBARS) and decreased intracellular glutathione levels. In summary, the physical properties of carbon nanoparticles may alter the CNM-induced concentration-dependent cytotoxicity and oxidative stress.
Asunto(s)
Supervivencia Celular , Nanopartículas/toxicidad , Nanotubos de Carbono/toxicidad , Estrés Oxidativo , Tamaño de la Partícula , Glutatión/análisis , Células HEK293 , Humanos , Interleucina-8/análisis , L-Lactato Deshidrogenasa/análisis , Peroxidación de Lípido , Sustancias Reactivas al Ácido Tiobarbitúrico/análisisRESUMEN
The eggshell waste has been value engineered to a nanocrystalline hydroxyapatite (HA) by microwave processing. To highlight the advantages of eggshell as calcium precursor in the synthesis of HA (OHA), synthetic calcium hydroxide was also used to form HA (SHA) following similar procedure and were compared with a commercially available pure HA (CHA). All the HAs were characterized by X-ray powder diffraction (XRD) method, Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and specific surface area measurements. Nanocrystalline nature of OHA is revealed through characteristic broad peaks in XRD patterns, platelets of length 33-50 nm and width 8-14 nm in TEM micrograph and size calculations from specific surface area measurements. FT-IR spectra showed characteristic bands of HA and additionally peaks of carbonate ions. The cell parameter calculations suggest the formation of carbonated HA of B-type. The OHA exhibits superior sinterability in terms of hardness and density than both SHA and CHA may be due to larger surface area of its spherulite structure. The in vitro dissolution study shows longer stability in phosphate buffer and cell culture test using osteoblast cells establishes biocompatibility of OHA.