Property Measurement and Testing of Powders for Pharmaceutical / Neutraceutical Production: Abstracts
Powder Handling Problems in the Process Industries
Prof. Mike Bradley
Industry makes widespread use of bulk particulates in manufacturing processes. Although the handling of these materials is often considered of secondary importance compared to the value adding steps that take place en route to the production of the end product, the direct impact of poor handling can result in significant process down time (through stoppages or inconsistent flow behaviour) – or in more extreme cases the complete suspension of a product marketing campaign. This presentation will review the importance of correct powder handling and consider some common design flaws.
Flowability Measurements for Powders
Dr. Rob Berry
The handling behaviour of bulk particulates through process is an aspect of plant operations whose efficiency has a direct impact upon the quality of an end product and profitability. Many techniques have been developed over the years to provide an indication of the flow behaviour of bulk particulates – some of which have gained a substantial foot hold in the folk lore of powder handling. This presentation will serve to de-mystify the scientific measurement of flow properties and highlight how these measurements can be used to trouble-shoot plant problems or to correctly design equipment.
Segregation and the Effect of Equipment Design
Richard Farnish
One of the more frequent problems encountered in industry is that of segregation. The effects of segregation can range from variation in dispensed weights (often resulting in increased "give-away" on pack weights) to assay variation through a batch (whether tabletted or dry fill). This presentation will consider how segregation occurs in processes and what options exist to mitigate theses effects.
Prediction of Segregation Potential of Bulk Particulates
Richard Farnish
Many problems that occur during full-scale production can be predicted from measurements of the bulk properties at the formulation stage. Similarly, production problems can also be diagnosed from an understanding of the properties of bulk particulates. The range of characterisations that can be undertaken is wide, but one of the more recent developments has been test equipment for predicting the propensity of powders of granular material to segregate when handled. This paper will examine two techniques that measure the effect of segregation for materials sensitive to surface effect (rolling particles during heap formation) and elutriation effect (particle interaction with counter directional air flows) segregation.
Evaluation of the Effect of Tablet Speed on the Compaction Properties Using Powder Batches with Different Flow Properties
Dr. Dennis Douroumis
It is well known that compression properties of tablet formulations depend on the particle size distribution and flow properties of the powder material. This is a challenge during scale up and technology transfer when powder flow properties are not consistent. This study examined the effects of tableting speed on the compressibility (solid fraction vs. compaction pressure), tabletability (tensile strength vs. compaction pressure), and compactibility (tensile strength vs. solid fraction) of different powder batches. It is proposed that the compactibility profile can be used as a predictor of tablet strength during formulation development and scale – up.
X – Ray Powder Diffraction as an Analytical Tool in Pharmaceutical Industry
Dr. Ian Slipper
X – ray Powder Diffraction (XRPD) is a standard technique used to determine structural information from crystalline substances. Its principal benefits are non – destructive phase identification of bulk powders including multi –phase assemblages. Within the pharmaceutical industry XRPD is used routinely to identify polymorphs and to assess the degree of crystalline/amorphous structure within active compounds. This presentation will demonstrate the fundamental principles of XRPD and proceed to give examples of qualitative and quantitative analysis. The problems and limitations of analysis will be discussed and the power of Rietveld full pattern profile fitting to mitigate these will be demonstrated.
Thermal Analysis as a tool in Materials Science
Dr. Milan Antonijevic
As an emerging discipline, pharmaceutical materials science correlates physical properties of active compounds and pharmaceutical ingredients with the performance of the finished dosage product. Small molecules of pharmaceutical interest can exist in many different forms called morphs, which have different degrees of order at the atomic level. Detection, characterisation and quantification of amorphous, polymorphs and pseudo-polymorhs have been recent subjects of research globally.
The thermal analysis (TA) has been extensively used to provide insight into structural changes on molecular level. Therefore, TA is the most important analytical tool for studying physico-chemical properties of materials. Amongst the most widely used thermal analytical techniques are thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and hot stage microscopy (HSM). Recently, differential mechanical analysis (DMA) and thermally stimulated current (TSC) spectroscopy draw attention to a new ways of monitoring motions and changes in the structure of materials.
Basic principles and applications of the most widely used TA techniques are main scope of the presentation. In addition, novel approaches and hyphenated techniques will be introduced.
Raman spectroscopy: a powerful analytical tool
Dr. Bruce Alexander
Raman spectroscopy gives information about molecular vibrations of a sample, similar to infrared spectroscopy. There is one important difference from a practical point of view. Water is largely invisible in Raman spectra which opens up the possibility of studying samples in water or wet environments, such as biological media. This talk will highlight some examples of the use of Raman spectroscopy and 2-D Raman imaging relavent to pharmaceutical, biomedical and materials research, e.g. polymorphism, polymer synthesis and biosensors.
Solid state NMR spectroscopy in drug analysis
Dr. Andrew P. Mendham
Due to inferior spectral resolution, solid state NMR spectra cannot be acquired in the same way as solution state NMR spectra. Since the introduction of magic-angle spinning (MAS), proton to carbon cross polarisation (CP), and high power proton decoupling techniques it has been possible to record high resolution solid state NMR spectra for a range of nuclei, typically including 13C. Solid state NMR spectroscopy is particularly sensitive to changes in the electronic environment of nuclei in a molecule.
Therefore, this has led to numerous pharmaceutical investigations in drug analysis. Routinely used applications include the ability to distinguish polymorphic states, pseudo-polymorphs and amorphous powders. Additionally, solid state NMR spectroscopy has proved to be useful in quantifying the relative amounts of polymorphic forms in a mixture, is a non-destructive technique and can be used to analyse drugs in pharmaceutical formulations.