**1. Introduction**

The problem of creating excellent biomaterials is a scientific challenge with enormous effects on the economy and health field. Today, synthetic zeolitic materials are probably an opportunity to prepare a successful alternative to traditional biomaterials. Study, chemical design, and manufacture of various inorganic structures allow to have active biomaterials which, in all applications, avoid unwanted responses of the body such as thrombosis [1], inflammatory reactions [2], and infections [3, 4]. In fact, the chemical and physical characteristics of the internal and external surfaces of these microporous materials lend themselves to well interact with exchangeable and reactive ions (e.g., toward drugs and microbes), with proteins (preserving their biological reactivity), and with cells (being noncytotoxic). Certainly, the chemical approach must be modified by replacing the traditional parameters used to characterize biomaterials with novel concepts such as contact angle with point of zero charge (PZC) and wettability with silicon/aluminum ratio. All the most advanced applications concern materials that occur in a membrane configuration [5], i.e., having chemical and physical selectivity whether they are pure materials, in mixture, or made of overlapping layers (composites). Zeolites, already in the form of crystals, have selectivity (shape selectivity, hydrophobicity/hydrophilicity), which can be modified by means of chemical functionalization, ion exchange, impregnation, etc.
