Incorporating Nigella sativa nanoemulsion into gelatin-guar gum films for enhanced healing of wound infections

Abstract

Aim: This study aims to investigate the impact of incorporating Nigella sativa essential oil nanoemulsion (NSNE) into gelatin (Ge) and guar gum (GG)-based films at various concentrations (0%, 2%, 4%, and 6%) and to evaluate the antimicrobial properties of the resulting films against common bacterial strains associated with wound infections.
 Methods: The nanoemulsion (NE) was obtained through ultrasonic irradiation. Polydispersity index, zeta potential, and particle size of NE were measured. For film preparation, gelatin (Ge) and guar gum (GG) were used, incorporating NSNE at concentrations of 0%, 2%, 4%, and 6%. Mechanical properties were evaluated using an universal testing machine, film thickness with a micrometer, and crystalline structure through XRD analysis. SEM was utilized for microstructure examination, and hydrophobicity was assessed by contact angle measurements. Antimicrobial activity was determined via the disk diffusion method against bacteria relevant to wound infections. Statistical analysis employed one-way ANOVA and Tukey post hoc tests with a significance level set at 5%.
 Results: The particle size, polydispersity index (PDI), and zeta potential of the nanoemulsion were measured as 296±4.85 nm, 0.569±0.2, and -35.2±07 mV, respectively. The incorporation of NSNE into GE-GG-based films demonstrated promising antimicrobial efficacy against common wound infection bacteria, including Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, Staphylococcus aureus, and Klebsiella pneumoniae. The films maintained mechanical integrity, with no significant alterations in tensile strength (TS) and elongation at break (EAB) (p  0.05). However, higher NSNE concentrations led to decreased hydrophobicity (p < 0.05) and structural changes, as evidenced by increased pores and cracks observed in SEM images. 
 Conclusion: This study highlight the potential of NSNE-containing films for wound healing applications, combining antimicrobial properties with a biocompatible film matrix.