Optimization and characterisation of water based keratin nanoparticles with Nigella sativa seed extract

Drug delivery technologies have been proven to improve treatment outcomes in many ways by enriching curative efficacy, reducing toxicity, increasing patient compliance and enabling entirely new type of medical treatments. In this study, keratin nanoparticles (KNPs) were prepared from chicken feathers and loaded with <i>Nigella sativa</i> seed extract (NSSE-KNPs) by adsorption method using doubled distilled water without using cross linkers, organic solvents and surfactants. The prepared KNPs and NSSE-KNPs were characterized by Dynamic light scattering (DLS), X-ray diffraction study (XRD), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The Encapsulation efficiency (EE) and loading capacity (LC) of NSSE-KNPs was found to be 82% and 70 % respectively. The drug release profile showed that KNPs exhibited slight difference in both acidic (pH 4.4) and basic (pH 7.4) environment. The prepared water-based KNPs and NSSE-KNPs also exhibited narrow PDI value and good negative <i>zeta potential</i>. The morphology of the keratin nanoparticles and <i>Nigella sativa</i> loaded keratin nanoparticles showed solid spheres, spherical and smooth shape distribution. The FTIR spectra revealed the possible hydrogen bonding formation after addition <i>Nigella sativa</i> seed extract to the keratin nanoparticles. In XRD analysis, both KNPs and NSSE-KNPs retained its chemical structure and crystallinity. The antibacterial effect was also observed for NSSE-KNPs against <i>Staphylococcus aureus</i> and <i>Escherichia coli</i>. Thus, the keratin nanoparticles loaded NSSE extract emerged as a potential candidate for future cancer treatment.