Bionanocomposites represent an emerging group of nano-structured hybrid materials. They are formed by the combination of natural polymers and inorganic solids and show at least one dimension on the nanometer scale (Darder et al., 2007). These hybrid materials retain the structural and functional properties of nano-structured materials. Meanwhile, the presence of biopolymer can reduce the public health and environmental risk of nano-sized material. The properties inherent to the biopolymers, that is, biocompatibility and biodegradability, open new prospects for these hybrid materials with special incidence in regenerative medicine and in environmental engineering (Darder et al., 2007). Fabrication of large-sized bionanocomposites, rather than nano-sized particles, can prevent possible harmful nanoparticles (NPs) intake by humans and living things. Synergistic assembling of biopolymers with inorganic nano-sized solids leads to multifunctional bionanocomposites which can be synthesized and applied in several areas for designed purposes. This thesis focuses on (i) the presence of toxic arsenic and antibiotics in Chinese drinking water sources; (ii) evaluation of a novel tailored bionanocompsite, namely chitosan goethite bionanocomposite (CGB), as removal agent for inorganic arsenic species from water; (iii) using clay mineral as adsorbent for removing gentamicin, an aminoglycoside antibiotic, from water, and assembling gentamicin-loaded clay with biopolymer hydroxypropyl methycellulose leading to a bionanocomposites film, namely gentamicin-montmorillonite- hydroxypropyl methycellulose (Gt-Mt-HPMC), to be used as burn wound dressing.
