Laser delivery and spectral study of a modern chlorine-containing drug for the treatment of onychomycosis at laser radiation with a wavelength of 405 nm

In an in vitro experiment, laser microporation of the nail plate and active laser delivery of Chloderm, a modern chlorine-containing photosensitizing drug, under the nail plate by laser radiation with a wavelength of 405 nm for the purpose of photodynamic therapy of onychomycosis is studied. The rate and efficiency of the nail plate ablation, as well as the rate of delivery of the drug under the nail plate are evaluated. The maximum ablation rate was 2600 $\pm$ 200 $\mu$m/s, and the ablation efficiency was 2.6 $\pm$ 0.2 $\mu$m/mJ. The maximum drug delivery rate was 5.3 $\pm$ 0.5 mg/s at $P$ = 1.0 W and an exposure time of $t$ = 0.3 s. The processes arising under the action of laser radiation on Chloderm and its aqueous solutions have been discovered and described for the first time. The results of studying extinction spectra of an aqueous solution of Chloderm in the range of 350–900 nm before and after exposure to laser radiation are presented. It has been shown that exposure to laser radiation with a wavelength of 405 nm and parameters sufficient for active laser delivery of an aqueous solution of the Chloderm preparation ($C$ = 5%) under the nail plate does not change the conformational state of the preparation, and therefore does not worsen its photodynamic and luminescent properties.