Polymeric nanoparticle physicochemical properties

Polymeric nanoparticles have attracted a lot of attention in the last years. Polymeric materials exhibit several advantageous properties including biodegradability and ease of functionalization. They also allow for a greater control of pharmacokinetic behavior of the loaded drug leading to more steady levels of drugs (Rawat et al. 2006). Furthermore, they enable the modulation of the physicochemical properties of the surface such as Zeta potential and hydro-phobicity/hydrophilicity. Many polymers used to develop nano- and... 

Several methods have been developed for preparing nanoparticles and are optimized on the basis of their physicochemical properties (e.g., size and hy-drophilicity) with regard to their in vivo fate after parenteral administration. The selection of the appropriate method for preparing drug-loaded nanoparticles depends on the physicochemical properties of the polymer and the drug. On the other hand, the procedure and the formulation conditions will determine the inner structure of these polymeric colloidal systems. Two types of systems with different inner structures are possible ... 

Over the last decades, several academic and industrial research programs have been focused on the development and production of appropriate biocompatible formulations that provide enhanced therapeutic performance. Three different strategies can be discerned that are applied separately or in combination (i) addition of excipients to proteins, such as protease inhibitors, penetration or absorption enhancers like bile salts, fatty acids, cyclodextrins or surfactants " (ii) modification of the physicochemical properties of proteins, e.g. by attachment of lipophilic or hydrophilic moieties or (iii) incorporation of proteins into polymeric or liposomal delivery carriers. " A variety of polymeric vectors has been developed and exploited for this purpose, including biodegradable nanoparticles, nanogels, micelles, polymer bioconjugates and soluble nanocomposites. These polymeric carriers are more extensively described in the following sub-sections. 

Moreover, polymeric nanoparticles can also be used for transdermal drug delivery, especially thanks to their small size (100 nm-1 p) enabling skin penetration. Interaction of nanoparticles with skin is strongly influenced by their physicochemical properties such as size, surface charge, polymer used, drug-loading efficacy and the manner of application [16]. 

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