An inclusion of mother liquor for example affects not only product quality for its desired applications but also storage stability, particularly with respect to CSD and morphology. This is of considerable importance to the pharmaceutical industry since polymorphic systems exhibit different physicochemical

properties due to the existence of these different crystal structures. Polymorphism influences the diswww.selleckchem.com/products/jq1.html solution characteristics, which along with CSD affects product formulation strategies and bioavailability [1, 2, 11–14, 23–26]. To understand how to form crystalline nanoparticles of hydrophobic active pharmaceutical ingredients (APIs) via this bottom-up process requires knowledge of Inhibitors,research,lifescience,medical the fundamental thermodynamic and rate processes involved in the generation of solid particles from a liquid phase. This involves solubility limits of the target species (with associated degree of supersaturation), nucleation and growth rates, and turbulence Inhibitors,research,lifescience,medical intensity to obtain the requisite mixing levels. It is the energy dissipation levels Imatinib clinical developed

by turbulence that determine the appropriate length and time scales required to control the phenomenological events occurring. Although these topics are discussed Inhibitors,research,lifescience,medical in some detail for specific applications elsewhere [11–22], a brief summary of each is included here for clarity of purpose. The various aspects and important parameters that affect the “bottom-up” crystallization process to be discussed are the following. Thermodynamics; describes phase characteristics, solubility limits and phase stability, establishing the driving force for crystallization. Nucleation and crystal growth; related to crystallization rates, particle sizes, and crystal

structures. Inhibitors,research,lifescience,medical Complications; describes some of the issues that need to be addressed in designing a process and getting the desired product Inhibitors,research,lifescience,medical quality. Flow Patterns, Mixing, and Transport Phenomena; describes the role of mixing in crystallization processes, relevant to processes that involve mixing of multiple streams, heating or cooling. Creating Nanoscale Entities; describes strategies of achieving mixing in the nanometer scale and techniques used. Energy Dissipation; gives an overview of the mechanisms that absorb energy during the process. Cilengitide 2.1.1. Thermodynamics Generating solids from a liquid phase is initiated by changes in the thermodynamic state of the solution, thereby reducing the solubility of the target species. Initiation may be through temperature adjustment(s), concentration changes, or by altering solution activity coefficients as in the solvent/antisolvent method. Phase stability is an important factor in determining both when and how fast events progress. The Temperature-Composition phase behavior, see Figure 1, can be used to illustrate some important concepts. A solubility curve represents thermodynamic equilibrium between the phases.