The Quality Assessment of a Mudtherapy Protocol by Surface Tensiometry Using the Contact Angle Method: the Japanese Biofango® Therapy Experience
The hydration state of human skin depends on good functionality of the epidermal selective barrier which is dictated by the stratum corneum. The link between the hydration state of skin and the functional effects of formulations and natural systems, such as thermal muds, has been demonstrated by several studies. Thermal muds have hydration properties owed to their water contents being up to 38% and due to the presence of clay minerals. The Tenskinmeter Versus Skin (TVS) mud index has been developed following the concept of the structure-surface approach, based on the determination of the contact angle of Fomblin HC/25® Perfluoropolyether (PFPE) on mud surfaces. The TVS mud index is a very sensitive “surface tensiometry marker” capable of describing surface free energy variations of peloids during the maturation process. The level of the TVS mud index is based on the hydrophobic, lipophobic and self-repellent characteristics of Fomblin HC/25® Perfluoropolyether (PFPE). Owed to the repulsive forces generated at the interface between the substrate and Fomblin HC/25® Perfluoropolyether (PFPE), the TVS mud index has been used to define the quality, conformity, and the degree of maturation of thermal muds. The TVS mud index has also been demonstrated to evaluate the functional and therapeutic efficacy of a peloid. Considering the importance of pelotherapy in the modification of the selective permeability of skin, and consequently its influence on the hydration state of stratum corneum and on the permeation of therapeutic substances, this work describes the development of a surface tensiometry model for the assessment and optimisation of Japanese Biofango® mud therapy. This has been done through the evaluation of skin hydration states before and after treatment with Biofango®, using water as a biocompatible test liquid, and determining the surface free energy of the used mud by implementing the Fomblin HC/25® Perfluoropolyether (PFPE).
Keywords: TVS mud index, euganean thermal muds, maturation process, contact angle method, mud therapy, skin hydration, biofango®