Resin phantoms as skin simulating layers

Abstract

In order to apply light treatment to skin, the absorption through the outer layers of the skin needs to be considered. Darker skin has a higher concentration of melanin in the epidermis and absorbs more light than fair skin. Ideally the effect of the skin treatment on the outer layers of the skin should be tested on in vitro multi layer skin models. This is not always feasible. For this work, phantoms were used together with skin cancer cells to test the effect of outer layer absorption on the efficiency of Photodynamic Therapy (PDT) treatment. Two resin based solid phantoms were prepared to simulate two different skin types. Cells were prepared and PDT treatment were done on cells with and without the phantoms, by keeping the total dose delivered to the cells constant at 4.5 J/cm2. Cell viability for the cells with the phantoms was less than without the phantoms and the differences are attributed to more uniform light distribution, but this needs to be investigated in more detail. The initial results of the experiments indicate that solid resin based phantoms can be used to optically mimic the effect of the outer skin layers.