Clay Nanoparticles

Clay Nanoparticles

The use of clays for healing purposes is widespread and is based on wellknown beneficial effects discovered after trials and errors or based on clinical–biological basis. This special issue is devoted to different aspects of clays and health. It is opened by a review on the beneficial and harmful effects of minerals in general and clay minerals. In the first section are reported the many applications of clay minerals in pharmacy and cosmetics indicating the broad variety of these materials as active principles, adsorbents, excipients, for drug delivery and in retard formulations: Use of clays as drug delivery systems: possibilities and limitations, uses of clay minerals in semisolid health care.

Clay minerals used in pharmaceutical formulations are: smectites, palygorskite, kaolinite and talc. These minerals can act as active principles or excipients. The properties for which they are used in pharmaceutical formulations are fundamentally: a high specific area and sorptive capacity, rheological properties, chemical inertness and low or null toxicity for the patient. Application of the clay is usually in the form of a powder, suspension, emulsion or gel. All these forms have expressed ion exchange, adsorption, emulsifying and electromagnetic properties.