Particle Counting & Sizing

The Accusizer range of particle counters, can count typically 500,000 particle counts in 1 minute, each by accurate single particle measurement.

The raw data generated by the SPOS (Single Particle Optical Sizing) detector, can present a particle size distribution as: distribution by particle number, distribution by surface area, distribution by volume and distribution by particle concentration. Due to the large number of particles measured, the resulting statistics are accurate and reproducible. The determination of particle concentration by the Accusizer, adds an extra dimension to size distributions by conventional laser diffraction methods. The accusizer achieves the high resolution of particle distributions, by using a SPOS (Single Particle Optical Sizing) detector. This can precisely define the tail of a distribution down to single counts in each distribution bin.

The particle tail distribution characterisation in absolute numbers, allows precise control of oversize fractions in particle populations. Possibly the most rigorous test for particle sizing is USP 788, where the US FDA requires pharmaceutical manufacturers to measure injectible fluids and report parts greater than 10 and 25 microns, to ensure that no large particles render the fluid dangerous for dispensing. USP788 specifies that the particle size distribution analyser must use SPOS technology.

The accuracy of the Accusizer can be demonstrated with very minute changes (parts per million) in a particle size distribution, being easily resolved. The sensor cell geometry ensures a wide dynamic range without compromising particle sizing accuracy. Sensor ranges available include 0.5 -400, 2 -1,000 and 5 -2,500 microns Measurements are Independent of matrix colour, density and refractive index. The Entegris Accusizer design is included in a range of laboratory liquid particle counters including:

1. Protein Aggregation Analyser

2. Emulsion Stability Analyser

3. Particle Contamination Monitoring: Entegris have developed a new version of the Accusizer range that is able to measure high concentration samples without the need to dilute the sample before measurement.

The traditional SPOS sensor works with a collimated laser light source. By replacing this with a focused laser source, it is possible to achieve both detection of smaller particles and also high particle concentrations in the sensor. The accusizer (Fx) model is able to count and determine particle concentrations on distributions as low as 0.1 microns in size and concentrations in excess of 1,000,000 particle/mL. The Fx is well suited for printer inks, emulsions, protein based drug formulations, clay slurries etc.

All models can be configured with various levels of automation including, stirring, sample flushing and autosamplers.