Laser delivery and spectral study of a modern chlorine-containing drug for the treatment of onychomycosis at laser radiation with a wavelength of 450 nm

The possibility of active laser delivery of a modern chlorine-containing photosensitizing drug Chloderm (Chloderm, Russia) under the nail plate by laser radiation with a wavelength of 450 nm for the purpose of photodynamic therapy of onychomycosis is studied. In an in vitro experiment, sequential laser microporation of the nail plate and active delivery of the drug under the nail plate by this laser radiation with an intensity of up to 200 W/cm$^2$ were investigated. The results of studying the absorption spectra of an aqueous solution of Chloderm in the range of 400–900 nm before and after exposure to 450 nm laser radiation are presented. It is demonstrated that sequential laser microporation and active laser drug delivery under the nail plate is possible at laser radiation intensity greater than 178 W/cm$^2$. It is shown that the maximum rate and efficiency of nail plate ablation by 450 nm laser radiation is achieved at an intensity of 200 W/cm$^2$ and is 2750 $\pm$ 30 $\mu$m/s and 1.47 $\pm$ 0.05 $\mu$m/mJ, respectively. The delivery rate of Chloderm under the nail plate is 1.15 $\pm$ 0.1 mg/s. It is shown that exposure to 450 nm laser radiation at the intensity of 200 W/cm$^2$ for a time sufficient to deliver the drug under the nail plate does not change the extinction coefficient of the drug at the laser wavelength and slightly changes the conformational state of Chloderm.