Physicochemical characterization of bioactive compounds in nanocarriers.

The encapsulation of bioactive compounds (BC) is an emerging technique for finding new medicines since it provides protection against degradation ambient factors before reaching the target site. Nanotechnology provides new methods for encapsulating BC and hence, for drug carrier development. Nanocarriers satisfactorily impact the absorption, distribution, metabolism and excretion rate when compared to conventional carriers. The nanocarrier material needs to be compatible and easily bind to the drug, and to be bio-resorbable. In this context, the physicochemical characterization of encapsulated BC is fundamental to guarantee quality, reproducibility and safety of the final pharmaceutical product. In this review, we present the physicochemical techniques mostly used today by researchers to characterize BC in nanocarriers, and the main information provided by each technique such as, morphology, size, crystallinity degree, long-term stability, efficacy of drug encapsulation, amount of BC released as a function of time and chemical bonds resulting from BC and nano-carrier interactions.