API Physical Characteristics Testing

Fig.1 API Physical Characteristics Testing.

Physical characterization testing is an important part of the Active Pharmaceutical Ingredient (API) quality control process and involves evaluating the various physical properties of APIs to ensure their identity, purity and compliance with established specifications. This testing plays a vital role in the formulation, manufacture and efficacy of pharmaceutical products.

Protheragen-ING is a leading provider of API characterization testing, offering specialized API characterization services to evaluate and define the physicochemical properties of APIs. Characterization testing typically involves identifying the molecular structure of a drug and its solid state (amorphous or crystalline) and determining its particle size, solubility, stability, viscoelasticity and flow behavior, among others.

Our scientists are experienced in a range of product types, from raw materials to APIs, and can apply a variety of physical characterization techniques, including UV spectrophotometry, high-performance liquid chromatography (HPLC), X-ray powder diffraction (XRPD), thermal analysis techniques and rheology.

Why Protheragen-ING?

Protheragen-ING's characterization tests provide insight into the physical properties of API materials, which are important for product formulation and counter-formulation, for quality control purposes to verify raw material specifications, and to help solve failure-related problems.

Physical properties can have an impact on drug performance, stability, product appearance, and processability. Understanding the physical properties of APIs at the earliest stages of drug development can give you a valuable competitive advantage and minimize potentially costly drug failures later in the development phase.

Available APIs Physical Characterization Testing

Appearance This involves visual inspection of the API for its color, clarity, and physical form (such as powder, crystals, or solid).
Solubility Evaluating the solubility of the API in different solvents helps in characterizing its physical and chemical properties. It is usually determined by observing the extent of dissolution at a specific temperature or by measuring the concentration of the dissolved API.
Melting Point/Range Determining the temperature at which the API changes from a solid to a liquid state can provide valuable information about its identity and purity.
Particle Size Distribution Analyzing the particle size distribution of the API is crucial because it can affect the dissolution rate, bioavailability, and stability of the final drug product. Techniques such as sieve analysis, laser diffraction, or microscopy may be used for this purpose.
Density Determining the density of the API provides information about its compactness, which can influence the dosage form design and manufacturing process.
Hygroscopicity This test evaluates the tendency of an API to absorb moisture from the surrounding environment. It helps in determining appropriate storage and handling conditions for the API.
Moisture Assessing the moisture content is important because excessive moisture can affect the stability and quality of APIs. Techniques like Karl Fischer titration or loss on drying methods are commonly employed.
Flow Properties Evaluating the flow properties of APIs is essential for proper handling during manufacturing processes. Techniques such as angle of repose, flow rate, or compressibility index can be used to assess the flow characteristics.
Bulk and Tapped Density These tests determine the density of the API under different conditions, which can provide insights into its packing and flow behavior.
pH Measuring the pH of an API solution or suspension is important for assessing its chemical stability and compatibility with other ingredients or dosage forms.

These are just some of the common physical property tests. Protheragen-ING can also customize specific tests based on the API and its intended use, as well as regulatory requirements and industry standards.

Fig.2 High-performance liquid chromatography.

If you are interested in this service and need more information, contact us and we will arrange for professionals to provide you with more information and discuss your specific requirements.


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