Bio-activity of superparamagnetic maghemite nanorods capped with dl-alanine

Abstract

The present research work explores an economic way of synthesizing maghemite (ᵞ-Fe2O3) nanorods through chemical coprecipitation method in which, ferric chloride was used, as one of the precursors and Sodium hydroxide as fuel with the assistance of dl-alanine, an organic surfactant. The obtained ᵞ-Fe2O3 nanorods have been characterized by X-ray diffraction, Fourier Transform Infrared Spectroscopy, Scanning electron microscopy, Transmission Electron Microscopy and Vibrating sample magnetometer techniques. X-ray diffraction results show that the synthesized ᵞ-Fe2O3 nanorods are in cubic spinel phase with improved crystalanity. The morphology and the size of the nanoparticles were confirmed by SEM as well as TEM. High resolution transmission electron microscopy (HRTEM) and selected area electron diffraction (SAED) of the sample have been performed. The FTIR spectra indicate the incorporation of dl-alanine on ᵞ-Fe2O3 nanorods. The saturation magnetization value of maghemite, measured by vibrating sample magnetometer corresponds to the typical superparamagnetic behavior. On examining the magnetic saturation (Ms) was found out to be 142emu/g, 57.7% higher than the bulk value, which is highly recommended for biomedical application. The antibacterial activity of ᵞ-Fe2O3 sample against gram-positive Streptococcus mutans, Staphylococus aures and gram-negative E.coli, Klebsiella pneumonia was investigated using Well diffusion method. The antifungal activity was tested by the same method against Aspergillus niger and Candida albicans. The MTT assay was employed to test the anticancerous activity of ᵞ-Fe2O3 against HT29 (coloncarcinoma) cell line. The sample shows positive control over antimicrobial species. The Lethal Dosage of the sample calculated to be 45.3149μg/ml, establishes its strong activity over HT29 cell line.