Development of kojic acid loaded collagen-chitosan nanoparticle as skin lightener product: in vitro and in vivo assessment.

In the present study, an ionic gelation and ultrasonic approach was performed to produce kojic acid (KA) loaded chitosan(CS)/collagen(CN) nanoparticle(NP) (CSCN-NP) which aimed to increase the dermal delivery and anti-pigmentation effect. To optimize the CSCN-NP the effect of the amount of CN was investigated. The results showed that increasing CN from 0 to 500 mg increased the mean particle size and entrapment efficiency of KA-CSCN-NP from 266.07 ± 9.30 nm to 404.23 ± 9.44 nm and 17.37 ± 2.06% to 82.34 ± 2.16%, respectively. Differential scanning calorimetry confirmed the amorphous form of KA in CSCN-NP, while scanning electron microscopy revealed that the nanoparticles were spherical. There was no chemical interaction between KA and the other components base on attenuated total reflectance-Fourier transform infrared spectroscopy. The skin permeability test showed that KA-CSCN-NP gel delivered more KA to the dermal layers (29.16 ± 1.67% or 537.26 ± 537.26 μg/cm) and receiver compartment (15.04 ± 1.47% or 277.15 ± 27.22 μg/cm) compared to KA plain gel. cytotoxicity assay demonstrated that the improved KA-CSCN-NP was non-toxic. Dermal irritating test on Wistar rats showed that the KA gel was non-irritating. Furthermore, KA-CSCN-NP was found to inhibit melanin formation to a greater extent than free KA and significantly inhibited L-dopa auto-oxidation (94.80 ± 2.41%) compared to pure kojic acid solution (75.28 ± 3.22%). The observations of this study revealed that the produced KA-CSCN-NP might be used as a potential nano-vehicle for KA dermal administration, thereby opening up innovative options for the management of hyper-melanogenesis problems.