API Particle Characterisation Size , Shape Analysis for Pharma Use

Importance of Morphology and Composition

Particle morphology, referring to the structure and form of particles, is a key parameter in industries such as pharmaceuticals, food, and cosmetics. It helps determine particle size and shape, as well as identify defects or irregularities that may impact quality. Morphology analysis can be conducted using light microscopy, scanning electron microscopy, or image-based methods.

Image analysis, in particular, enables precise and high-throughput measurement of individual particles, providing consistency and accuracy that surpasses manual microscopy. It is widely recognized for delivering robust morphological insights across a diverse range of particle types.

Broader Physical Parameters

In addition to morphology, particle characterization may include surface area, density, and refractive index. These parameters contribute to understanding the physical and chemical behavior of particles and are useful in predicting their interactions, performance, and stability in various formulations.

Relevance to Pharmaceutical Applications

In the pharmaceutical industry, API particle characterization provides a detailed understanding of the size, shape, and structure of a drug compound. These characteristics impact powder flowability, porosity, bulk density, hygroscopicity, blend uniformity, and compressibility—all of which influence key manufacturing steps such as granulation, mixing, compression, and coating.

Crystal size distribution (CSD) or particle size distribution (PSD) plays a crucial role in determining drug solubility, dissolution rate, and shelf life. Accurate particle characterization helps maintain consistent product quality and therapeutic efficacy.

Risk Mitigation in Drug Development

Characterizing physicochemical properties at the particle level helps mitigate risks early in the drug development process. It aids in identifying variability, reducing uncertainty, and ensuring quality control of solid oral dosage forms, particularly for APIs that are sensitive to size-related performance changes.

Analytical Techniques and Challenges

The United States Pharmacopeia (USP) provides the following monographs for particle size measurement:

USP <776>: Optical Microscopy for particle size, shape analysis, static image analysis, and crystallinity
USP <429>: Laser Diffraction for particle size measurement

A critical challenge is identifying agglomerated API–API particles, which can skew particle size distribution (PSD) results. Image analysis offers a solution by accurately distinguishing and measuring individual particles. It is increasingly favored for its ability to develop dependable workflows across a wide range of materials.