Dealuminated Zeolites in Biological Systems

Abstract

Recent direct and indirect evidence have pointed to both biological reactivity and toxicity of micro- and nano-particles. Particle size appears to be a decisive factor and particles can enter cells in two ways; either through endocytosis, were particles enter the cell in an endosome; or by otherwise passing the cell membrane directly into the cytoplasm. Endocytosis covers sampling of small volumes of fluids and soluble molecules from the milieu surrounding the cell, as well as internalization of large particulate matter such as whole cells or cell fragments from the immediate vicinity of the cells. With respect to toxicity, it is important to identify the size and the chemical composition at which biological systems no longer regard the extraneous matter as particles and hence the material enters the cells directly, through other mechanisms than endocytosis.