Particle Size Analysis

The Malvern Mastersizer 2000 is used as the primary source for particle size characterisation. Particle size analysis is an essential step in understanding the behaviour of powders. The device is easy to use with a simple approach to sample dispersion, instrument control and measurement. The Mastersizer has a broad measuring range from 0.02 – 2000 µm and operation is automatic by using standard operating procedures (SOPs) via the computer software. Typical applications include pharmaceuticals, chemical, foodstuffs and emulsions. Currently used are two methods for presenting samples: Hydro S, Scirocco. The Hydro S is a wet dispersion ideal for laboratory use because of its small capacity, 50-120 ml, ensuring a small volume of solvent waste. The dispersion mechanism incorporates a single shaft pump and stirrer as well as an ultrasonic probe. The stirrer speed and probe are variable ensuring full dispersion of the sample. The Scirocco is a dry dispersion unit with a variable vibration feed rate and dispersing pressure, ranging from 0-4 bar with a precision of 0.02 bar. Dispersion is achieved through accelerating particles within the compressed air stream, together with particle-particle and particle-wall collisions.

The Mastersizer 3000 (Malvern Panalytical) is a laser diffraction system, capable of determining the particle size distribution of a sample, ranging from 3.5 mm down to 10 nm. The Mastersizer 3000 is capable of both wet and dry dispersion, with either method available to the user, depending upon their sample properties.

The Morphologi G3 (Malvern Panalytical) is a dry particle characterisation technique, capable of conducting particle size, shape and number analysis for particles ranging from 0.5 microns up to several millimetres. The technique uses microscopes, of user-specified magnification, to record images of the user’s sample over a period of time, with these images then analysed to produce a particle size distribution. The Morphologi G3 also features a sample dispersion unit, where the dispersion pressure and duration can be modified to suit the mechanical properties of the user’s sample.

The new Malvern Spraytec spray sizing system provides users with in-situ, real-time measurements of the droplet size distributions produced by spray and aerosol devices. Using the technique of laser diffraction, it has been specifically designed to address the unique requirements of spray characterization, yielding robust, reproducible results for diverse products such as agrochemical sprays, fuel injection systems and pharmaceutical inhalers. The Spraytec can measure spray size distributions over an extremely broad dynamic range 0.1 – 2000 µm with an acquisition rate of up to 10 kHz.