Given the fact that the majority of drug substances are produced by crystallization, a single chemical entity generally can adopt two or more crystalline phases, and such phenomenon can be termed as the polymorphism. Although the morphology, solvates and particle size-distribution are considered to be the important properties for active pharmaceutical ingredients, polymorphs, the uncontrolled occurrence of multiple physical forms, can signally influence the performance of drugs in many ways such as stability, solubility and the pharmacological activity. In this case, there is an increasing attraction of polymorph screening for many innovators and generic companies that take pharmaceutical and intellectual property rights aspects into consideration.
It is mainly composed of the methods of single crystal and XRPD. As one of the most important quantitative quality control approaches for crystalline drugs, X-ray analysis possesses many advantages such as high accuracy, fast detection time, and low-requirements for pre-processing of samples.
Such method is established on the principles of thermodynamics and properties of matter thermodynamics. According to the detection properties, thermal testing can be divided into DSC (differential scanning calorimetry), TGA (thermal gravimetric analysis), melting point, hot-stage microscopy, EGA (escape gas analysis) and DTA (differential thermal analysis).
Mid FT-IR, Raman and Solid-state-NMR are the three types of most commonly used spectroscopy techniques. Based on the fact that different polymorphic forms of an API lead to varying molecular structure, using the spectroscopy approaches can efficiently distinguish diverse crystal forms through determining the frequency, peak shape, peak position and peak strength.
HT crystallization system is the methodology that uses a combinatorial approach to solid form generation and that is capable of exhaustively screening for crystal polymorphism. The large arrays of conditions and compositions which are processed in parallel enable this approach to be used for investigation of a broader range of targets and determining the outcome in an automated fashion with only a few milligrams of sample.
We also provide additional polymorph analysis and screening methods including microscopy, DVS (dynamic vapour sorption), solubility/dissolution, PLM (polarized light microscopy) and SEM (scanning electron microscopy).
Fully aware of the prevalence and importance of polymorphism in pharmaceutical compounds, scientists from BOC Sciences are dedicated to solving specific problems related to the preparation and selection of the right crystal forms throughout all the stages of drug development. Armed with enough professional knowledge, our experts can provide you with a package services including experimental design, protocol optimization, compounds analysis, polymorph screening and finally formulation development.
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