Cyclodextrin decorated nanosponges of sesamol: Antioxidant, anti-tyrosinase and photostability assessment

Abstract

Sesamol (SES), a natural phenolic bioactive, is endowed with benefits in food and pharmaceuticals. However, its utility is compromised by certain unfavorable physicochemical characteristics, particularly poor stability. Therefore, present work is aimed at formulating novel SES loaded cyclodextrin nanosponges (CDNS) to protect the drug from degradation. For this purpose, blank CDNS were fabricated employing solvent evaporation technique and subsequently SES loading via lyophilization. Characterization of SES-CDNS was carried out by Fourier transform infrared analysis, differential scanning calorimetry, and nuclear magnetic resonance. These nanostructures were also evaluated for entrapment efficiency, particle size, polydispersity index, and zeta potential. Further, photostability assessment was conducted for SES-CDNS, along with stability evaluation. Antioxidant potential of SES was determined using DPPH assay, after its encapsulation and storage. Lastly, in vitro anti-tyrosinase assay was also performed for SES-CDNS. Results demonstrated that SES was successfully entrapped in CDNS having size in nano-range (189.46 ± 6.57) and assuring high encapsulation efficiency (90.66%). The findings of the photostability evaluation showed that CDNS was able to protect SES from photodegradation. Furthermore, oxygen radical absorbance capacity was found preserved for SES, especially when encapsulated in CDNS. No significant differences were observed after three months storage (at room temperature), with regard to loss of structural and functional features of SES. Hence, the results confirmed that nanoformulation is ideal for encapsulation of SES to enhance its physicochemical stability and to preserve antioxidant and anti-tyrosinase activity of this bioactive.