A new simple method of quantitative analyze of pheomelanin in hair and cancer cells by ESR method (Evaluation of antioxidant effect of ascorbic acid)

Author: Maia Topeshashvili
Keywords: eumelanin, pheumelanin, ascorbic acid, ESR Spectroscopy
Annotation:

Annotation The work is dedicated to the new simple method to define relative concentration of pheumelanin and eumelanin and also the quantity of pheumelanin in the human hair. On the basis of the research process we created a calibration curve, which allows us to define eu/phe concentrational ratio expressed in percents, using gx factor and resonance linewidth of ESR signal. The curve is obtained by extrapolation of the linear portion in the experimental curve of phe/eu concentration ratio by gexp factor of the sample. Extrapolation was performed towards the value of g- factor of the black hair. Not only the gexp factor, but resonance linewidth of ESR signal Hpp, which represents tha distance between the points of maximum curvature of the spectra, also is valuable parameter which can be used to evlauate phe/eu relationship. The width of the central component of the pheumelanin triplet is greater, than the width of eumelanin singlet, which is superimposed by ESR spectra of the pheumelanin. Therefore, if the concentration of pheumelanin is increasing, the width of central component of the spectra is also increasing, and this growth is in good corellation with the increase of the gexp factor values. Another main goal of our work was to define an optimal concentration of the ascorbic acid using Electron Spin Resonance Spectroscopy, which can be used in sun protection creams, as well as for treatment purposes of different skin diseases, especially skin melanomas. Human hair, as well as the skin, contains eumelanin and pheumelanin and the color of the hair and skin itself is defined by the relative concentration of these two components in the skin and hair. Both eumelanin and pheumelanin carry magnetic properties. Therefore, each Electron Spin Spectra of the hair represents a superposition of two: eumelanin singlet and pheumelanin triplet. What about Ascorbic acid, it is known to have very good reduction properties. At the same time ascorbic acid itself carries diamagnetic properties and can’t be seen on the ESR spectra, but after oxidation it gives ESR signal as a duplet with the Hyperfine coupling at 1.8 gauss (0.18 mT). The research has been performed on black and red hair. the reason was that the maximum concentration of eumelanin is in black hair, while the red one is characterized with the maximum concentration of pheumelanin. aim of our research was to define an optimal concentration of ascorbic acid, which will be enough for completely revealing its antioxidant properties and at the same time we wanted to find the time range, where the influence would be the most active. As the experiments showed, the optimal concentration of ascorbic acid, which is able to completely remove ESR signal of pheumelanin is 10mmole. The results, if using more concentration of ascorbic acid, rather then 10mmole gives the same results as 10mmole, so we considered this concentration as the optimal one. The results also showed, that ascorbic acid has an influence not only on the free radicals of pheumelanin, but also on the free radicals of eumelanin. But optimal dose concentration for both is the same. What about kinetics, manly the time range where the influence of ascorbic acid is the most active, as it was found out, the most effective time range is the first 3 hours for black and 9 hours for red hair, as the sharpest changes in the parameters were evident exactly in this period of time. Though, we can consider the first 3 hours as the most active period of influence, as the changes in the parameters for red hair are very insignificant, while for the black hair they doesn’t exist at all. It is important to mention also, that influence of UV and visible light and event of free radical generation in black and red hair can be used as a method to study antioxidant properties of different antioxidants. For such kind of studies ESR Spectroscopy is very useful and informative method. These studies will give us possibilities to have more data for using them in cosmetology and dermatology and also to make arrangements for preventing different pathological processes and diseases in the skin.