Preparation, characterization, and evaluation of anti‐tyrosinase activity of solid lipid nanoparticles containing Undecylenoyl phenylalanine (Sepiwhite®)

Abstract Background Hyperpigmentation is darkened patches or spots on the skin occurred by increased melanin. Undecylenoyl phenylalanine (Sepiwhite®), as a commercial lipophilic derivative of phenylalanine, is a powerful new brightener that can be used in the treatment of skin pigmentation disorders. Aims Solid lipid nanoparticles (SLNs) increase the efficiency of hydrophobic drugs. The current study aimed to prepare and characterize SLNs containing Sepiwhite (SEPI‐SLN). Methods In this study, an optimized SEPI‐SLN formulation was selected by applying the response surface method. In vitro drug loading content, the release profile of SEPI, and cell viability were investigated. The permeation rate of SEPI‐SLN was also compared to conventional cream containing Sepiwhite (SEPI‐CREAM). Furthermore, the anti‐tyrosinase activity of Sepiwhite was also evaluated. Results The optimized formulation showed a spherical morphology with particle size and entrapment efficiency of 218.6 ± 11.1 nm and % 87.31 ± 0.65, respectively. Differential scanning calorimetry (DSC) analysis confirmed SEPI‐loaded SLN formulation with no drug‐lipid incompatibility. The in vitro permeation experiment revealed the enhanced cutaneous uptake of SEPI‐SLN. The results also showed that Sepiwhite could stop melanogenesis with inhibition of the tyrosinase enzyme. Conclusion Our findings confirm that SLNs could be a proper nanocarrier for the relevant usage of Sepiwhite as a powerful brightener agent.