A review of melanin sensor devices

Abstract

Knowing how readily the skin produces melanin is invaluable in reducing photochemical and phototherapy overtreatment in dermatology and also in reducing the risk of actinic skin damage and skin cancer from excessive radiant light exposure. The commonly used Fitzpatrick skin type (FST) classification scale is often used to subjectively assess ultraviolet light sensitivity and susceptibility to sunburn following significant sunlight exposure. However, the FST scale falls short in the assessment of nonwhite skin types. Alternatively, commercially available melanin sensor devices, called melanometers, can be used to objectively quantify useful skin parameters such as the epidermal melanin concentration (EMC). This study reviews commercially available melanometers and their use in quantifying epidermal melanin concentration (EMC) and the individual maximum safe radiant exposure (IMSRE) for an individual in clinical, workplace and community settings.

Keywords: Epidermis; Melanin; Melanometers.

Fig. 1

a A typical absorption spectrum, or apparent absorbance, of human melanin in vivo versus wavelength in nanometers. This was accomplished by calculating the logarithm (base e) of the ratio of the remitted intensity from vitiliginous to normal skin, at adjacent sites of the same volunteer. The straight line represents the best fit through the experimental points in the range 620–720 nm. The correlation coefficient for the straight line is 0.982 (Kollias and Baqer 1987). Reprinted from Journal of Investigative Dermatology, 89, Nikiforos Kollias, Ali H. Baqer, Absorption Mechanisms of Human Melanin in the Visible, 400–720 nm, 384–388, Copyright 1987, with permission from Elsevier. b Chemical structure of the eumelanin monomers 5,6-dihydroxyindole (DHI) (1) and 5,6-dihydroxyindole-2-carboxylic acid (DHICA) (2) (Watt et al. 2009)