Physical Properties

Pharmaceutical testinPhysical Properites

Physical Testing

We don’t just measure, we understand

Our experience in materials testing covers:

  • surface science
  • physical form
  • thermal analysis
  • issues relating to solid dosage form and inhaled drug delivery

Routine physical properties analysis includes:

  • Full preformulation, logP, pKa, solubility, stability, size, form etc
  • Studies on batch-to batch variability in production / problem solving
  • One off tests, rapid high quality turn around as you need them
  • Individual tests (e.g. XRPD and DSC) to GMP quality standards
  • Rapid reliable excipient compatibility

Whatever your needs in the physical characterisation arena we can help.

Physical Properties services offered by Pharmaterials include:

Raman Mapping
Raman Mapping - physical sciences To gain an understanding of the distribution of the active and excipients, to know which physical form is present to identify patent infringement, counterfeit identification and batch variability issues, we offer our state-of-the-art Raman mapping service. Recently applications have included:
    • studies of physical form present in creams and ointments – for very low concentration formulations
    • Investigations of active and excipient distribution in granules.
    • Probing amorphous solid dispersion formulations for phase separation.
Amorphous Content Screening

Amorphous Content - physical properties - pharmaceuticalsDuring the manufacture and processing of active drug substances, amorphous regions or defects may be induced due to the shear physical forces applied (such as milling or impaction, compression, attrition, etc).

Although the percentage of amorphous content introduced in this way is usually low (in the order of ~ 1% w/w), its location primarily on the surface of what are usually small particles gives it a disproportionate control on the properties of the material. This can dramatically change the physical properties of the compound, such as altering the flow properties, specific surface area, compressibility and dissolution rate etc.

It is therefore of the utmost importance to strictly monitor the processing of drug substances with regards to the generation of amorphous material, as well obtain a comprehensive understanding of its physical and chemical stability.

Typical studies include

  • Selection of the best method for your API for the quantification of amorphous content (isothermal nanocalorimetery, solution calorimetery, Raman sepctroscopy, NIR spectroscopy or others)
  • Use the optimum method for the quantification of amorphous content (down to 0.5 %), if required providing full method validation
  • Identification and monitoring of the glass transition temperature (Tg)
  • Determine relaxation times as a function of temperature and relative humidity
  • Determine amorphous stability with regards to hygroscopic behaviour
  • Monitor recrystallisation behaviour as a function of temperature, time or relative humidity
Physical Characterisation Techniques
Pharmaterials has a wide range of instrumentation including inverse gas chromatography (IGC), thermal analysis (Hyper-DSC, isothermal calorimetry, solution calorimetry, high sensitivity DSC), confocal Raman mapping, DVS, X-ray diffraction, surface area, particle sizing and many more. Some examples are listed below:
    • X-ray Powder Diffraction Studies
    • Thermal Studies – DSC, Hyper-DSC, TGA, Isothermal Nanocalorimetry, Solution Calorimetry, High Sensitivity Scanning Calorimetry, DSC-Raman and DSC-NIR
    • Microscopy – Optical, Raman SEM and Hot-Stage
    • Sorption / Desorption – Water and organic vapour (coupled NIR probe), Nitrogen BET
    • Powder Surface Characterisation – Inverse Gas Chromatography, Confocal Raman Spectroscopy
    • Bulk Properties Determination – Specific surface area, porosity, bulk and tapped density, powder flow
    • Dissolution Testing – Intrinsic and non-intrinsic methods, HPLC, UV, ELSD analysis
    • Chromatography – HPLC-UV/ELSD
Pharmaterials have a very strong link between materials characterisation and inhaled drug delivery formulation. Our methods for amorphous quantification are the basis of those adopted by Pharmacopoeias and are accepted by regulatory bodies. The ability to predict and control the performance of an inhaled product is valuable in expediting the development of an active ingredient into a viable and reproducible formulation. However, due to the complexities of drug/carrier interactions and inevitable changes of particle integrity as a result of physical processing (such as micronisation), it is often very difficult to identify the specific paramaters that are causing the variability. Types of analysis include:
    • Particle size and shape distribution
    • Surface morphology and physical form identification
    • Spatially resolved surface chemistry & structural composition
    • Changes in surface energies after processing
    • Identification of component migration / segregation & contamination

At Pharmaterials we do not believe in one method being best for every sample. We use our decades of experience in multiple methods in order to find and use the best science and solution for you. Contact us to discuss your requirements