Dr Alan Rawle, applications manager for Malvern Instruments, has been invited to speak as part of the Brian Scarlett Memorial Session at the 7th World Congress for Particle Technology (WCPT 7), which takes place in Beijing, China, from 19-22 May.

Dr Rawle’s presentation will discuss ‘Sampling – another Cinderella of particle size analysis’ and he will highlight the importance of representative sampling for particle size analysis, explaining how to employ statistical methods to obtain accurate and reproducible results.

“Brian Scarlett was one of the most recognized, respected and effective leaders in particle technology and it is a real honor to be contributing to this memorial session,” said Alan Rawle.

“He often said that sieving or screening was the Cinderella of particle size analysis because it does the dirtiest work and attracts little attention. In my view the same statement rings true for representative sampling, so this is a fitting event at which to explore this aspect of particle sizing.”

In ‘Sampling – another Cinderella of particle size analysis’, Dr Rawle will argue that although sampling is the most common source of errors in particle sizing, frequently it does not receive enough attention. Analytical techniques including laser diffraction, dynamic light scattering and electron microscopy measure samples accurately but the results may not be representative of an entire material or product, owing to heterogeneity or variations in distribution in the bulk material. He will demonstrate how statistical methods may be used to calculate the minimum sample mass needed to meet a required level of precision, and the theoretical best achievable precision, based on the heterogeneity of the sample.

In other congress sessions, Dr Rawle will also present ‘Best practice in laser diffraction: a robustness study of the optical properties of silica.’ Here he will explore the importance of understanding the factors that can affect the particle size data generated by laser diffraction analysis and will provide guidance regarding the specific issue of optical property optimization.

Particle characterization is a central part of Malvern’s broad materials characterization portfolio, which includes analytical instruments for measuring particle size, particle shape, zeta potential, protein charge, molecular weight, mass, size and conformation, and rheological properties as well as chemical identification. These complementary analytical solutions have applications throughout industry, from pharmaceuticals and biopharmaceuticals to bulk chemicals, energy and the environment.