Fluorescent microscopy evaluation of diode laser effect on the penetration depth of turmeric (Curcuma longa) extract cream on skin tissues of Wistar rats

The study investigates the effect of diode laser exposure on curcumin’s skin penetration, using turmeric extraction as a light-sensitive chemical and various laser light sources. It uses an in vivo skin analysis method on Wistar strain mice. The lasers are utilized at wavelengths of 403 nm, 523 nm, 661 nm, and 979 nm. The energy densities of the lasers are 20.566 J/cm², 20.572 J/cm², 21.162 J/cm², and 21.298 J/cm², which are comparable to one another. The experimental animals were divided into three groups: base cream (BC), turmeric extract cream (TEC), and the combination laser (L), BC, and TEC treatment group. Combination light source (LS) with cream (C) was performed with 8 combinations namely 523 nm ((L1 + BC) and (L1 + TEC)), 661 nm ((L2 + BC) and (L2 + TEC)), 403 nm ((L3 + BC) and (L3 + TEC)), and 979 nm ((L4 + BC) and (L4 + TEC)). The study involved applying four laser types to cream-covered and turmeric extract–coated rat skin, with samples scored for analysis. The study found that both base cream and curcumin cream had consistent pH values of 7–8, within the skin’s range, and curcumin extract cream had lower viscosity. The results of the statistical analysis of Kruskal–Wallis showed a significant value (p < 0.05), which means that there are at least two different laser treatments. The results of the post hoc analysis with Mann–Whitney showed that there was no significant difference in the LS treatment with the addition of BC or TEC when compared to the BC or TEC treatment alone (p > 0.05), while the treatment using BC and TEC showed a significant difference (p < 0.05). Laser treatment affects the penetration of the turmeric extract cream into the rat skin tissue.