Suspensions of special clays in mineromedicinal waters to be used in therapeutics

Clays are frequently used in complementary and alternative medicine, including balneotherapy. Therapeutic muds are used for topical administration of mineral medicinal waters in the treatment of illnesses of the locomotor apparatus, including osteoarthritis and rheumatologic diseases. Clays are used in muds as vehicles of the mineral medicinal water, to obtain inorganic gels with rheological and thermal properties suitable to be topically applied. Despite their demonstrated longevity, the use of clays in therapeutic muds greatly requires comprehension of the attributes that sustain their use. Whit these premises, clay samples currently used in several spa centers of southern European/Mediterranean countries were studied to asses their identity, purity, richness and safety. Two of the studied samples were selected for posterior studies because of their superior quality. Preparation procedures of therapeutic muds have been orally transmitted since ancient times, being accepted that muds require a “maturation” process to achieve the desired therapeutic results. As a first step in the comprehension of this procedure, the influence of “maturation” on the structure and properties of concentrated suspensions prepared with pharmaceutical grade clays (selected as model materials because of their known quality attributes) was studied. Rheological properties of the studied systems were related to aggregation states and networking mechanisms. These behaviour patterns found during maturation were used in subsequent steps of the thesis. In particular, the two selected clays from spa centers were used to prepare thermal muds with mineral medicinal water from thermal spring of Graena (Cortes y Graena, Granada, Spain). Muds were matured for three months and characterized over time for those properties considered relevant in view of their topical administration and possible mechanisms of action. It is accepted that heat plays a fundamental role in the beneficial effects of thermal mud therapy together with the possible transfer across the skin barrier of chemical elements presented in muds. In the studied case, maturation increased the release of cations from therapeutic muds but did not improve their thermal properties. Accordingly, the therapeutic effects associated with thermophysical mechanisms would not require mud maturation. Maturation would be only relevant to improve chemical effects of the muds.Tesis Univ. Granada. Programa Oficial de Doctorado en: Medicina Clínica y Salud PúblicaLa presente Tesis Doctoral ha sido financiada por el proyecto del Plan Nacional de I+D+i CGL2010-16369 y por el Grupo de Investigación CTS-946 de la Junta de Andalucía. La doctoranda ha disfrutado de una beca del Programa JAE Predoctoral