Cultured human keratinocytes for optical transmission measurement

Abstract

The challenges of measuring optical properties of human tissues include the thickness of the sample, homogenization, or crystallization from freezing of the tissue. This investigation demonstrates a method to avoid these problems by growing optically thin samples of human keratinocytes as a substitute for ex vivo epidermis samples. Several methods of growth were investigated. Resulting samples were measured on a spectrophotometer for transmission between 300 nm and 2600 nm. The efficacy of the cell growth was confirmed with histological examination of several cultured keratinocyte samples. Limitations were the requirement to measure samples immediately after removal from the incubation environment, and the absence of the irregular structures of normal skin such as hair and glands.

Evaluation of cell viability and metabolic activity of a 3D cultured human epidermal model using a dynamic autoradiographic technique with a PET radiopharmaceutical

“…However, the image-derived radioactivity concentration per volume or thickness is not easily obtained. It will be possible to calculate the value using data on the thickness distribution of tissues, which can be estimated from the radiation and optical 24,25 attenuation coefficient map. The radiation attenuation coefficient can be obtained from the uptake value difference in the autoradiographic images between no tissue (background) and no uptake tissue (at time zero) similar to the attenuation correction using transmission data in PET 26 (see Supplementary Fig.…”

Relationships of skin depths and temperatures when varying pulse repetition frequencies from 2.0-μm laser light incident on pig skin

“…Last, the dermis has been reported to be from 981 m to 4000 m thick. 42 This places the optical penetration depth of 2.0-m laser light within the dermis if absorption is dominant in skin. If skin is a turbid medium with scatter dominant, then the penetration depth is deeper into or beyond the dermis.…”