Argan oil as a pretreatment of human hair before exposure to oxidative damage: Attenuated total reflectance and protein loss studies

Abstract

Introduction: In recent years, argan oil has gained increasing interest in hair care products. In this study, attenuated total reflectance technique was utilized as a fast method and the results were compared to protein loss measurements in order to show the preventive effect of argan oil pre-treatment on excised human hair after oxidative hair damage.

Methods: Hair tresses were divided into three groups: in group-1; they were damaged using oxidant agent solely, in group-2 and 3; hair were pre-treated with argan oil before undergoing the oxidative damage. In group-2, the oil was removed by physical cleaning but in group-3 the oil was removed with a washing procedure. ATR (attenuated total reflectance) spectrum was recorded for different samples. Quantitative studies of protein loss in hair samples were performed by Lowry method. The antioxidant properties of argan oil were also measured in vitro using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) protocol, which determined the ability of the oil to scavenge the DPPH free radicals.

Results: The amount of protein loss with oil pre-treated groups was reduced significantly. The ATR spectrum showed oil deposition on hair even after washing. Four distinctive ATR peaks were changed during oxidation. The changes in peak height values were linear. The antioxidant property measured with DPPH method led to a IC50 value of 59 µg/ml.

Conclusion: Argan oil pre-treatment was effective in protecting hair against oxidative damage. ATR outcomes were in accordance with protein loss results. In this study, the ATR testing method as a fast technique was used efficiently in quantification of hair damage.

Keywords: ATR; argan oil; hair; oxidative damage; protein loss.