Pharmaceutical Crystals: Development, Optimization, Characterization and Biopharmaceutical Aspects

*Agustina Bongioanni, Maria Soledad Bueno, Belén Alejandra Mezzano, Marcela Raquel Longhi and Claudia Garnero*

## **Abstract**

In the solid state, the active pharmaceutical ingredients tend to exhibit crystalline order. In this regard, the interest in the crystalline solid state has expanded to include single-component compounds as well as multicomponent systems such as salts, hydrates, solvates, and co-crystals. The study of crystalline behavior is recognized as an essential component of preformulation research in pharmaceutical sciences and industries. The crystalline form can impact the drug properties such as solubility, dissolution rate, stability, hygroscopicity, and toxicity profile. Therefore, each solid form must be appropriately identified and characterized because it will affect the drug formulation, including the pharmacokinetic, pharmacodynamic, and safety properties of the formulation. In this context, this chapter will cover topics such as synthesis approaches (including nucleation and crystallization procedures), crystal polymorphism, solid state characterization techniques and the impact of crystals on physicochemical and biopharmaceutical properties.

**Keywords:** drugs, crystallization, characterization, polymorphism, biopharmaceutical properties
