Immersion/soaking/precipitation

Figure 13.1 Different fabrication processes for phosphate nanocomposites (a) immersion, soaking, precipitation (b) electrospinning (c) (bio)plotting (d) freeze-casting (e) rapid prototyping from computer-aided data and (f) chemical synthesis.

Immersion, soaking or (alternatively) dipping accompanied with subsequent precipitation is one of the simplest methods to incorporate calcium phosphate compounds into organic carriers and is therefore widely used and reported. In contrast, chemical synthesis of polymers that mimic natural processes such as HA nucleation or phos-phatation are rather seldom reported because large chemical background knowledge as well as a special equipment are needed. 

Immersion or soaking is one of the simplest methods to incorporate calcium phosphate compounds into organic carriers (Figure 13.1(a)). The basic interaction between such precipitated calcium phosphate species and the organic compound is based on adhesion, in other words on ion-dipole interactions or van der Waals forces (dispersion forces) between the two major components. Hence, many studies include this simple processing step in their protocols [20,45,49]. 

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