Malvern Particle Size Analyser

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The world’s leading particle size analyzers. Malvern Panalytical is the world’s leading supplier of particle size analyzers. Our systems enable our customers to maximise productivity and develop better products faster. The control and understanding of particle size and size distribution is key in understanding both physical and chemical properties. Mastersizer particle size analyzers using laser diffraction technology are the worlds leading particle size analyzers. Fallout new vegas laser rifle. What are the benefits of owning a Malvern particle size analyzer? Wet or liquid dispersion method development for laser diffraction particle size distribution measurements. Particle size analysis is to measure the particle size distribution of the individual or primary particles in a given sample. According to the National Institute of Standards and Testing (NIST), a primary particle is defined to be the smallest identifiable subdivision in a particulate system (1). It is important that the.

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Malvern Particle Size Analysis Principle

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Malvern Particle Size Analyser Principle

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  • Particle size is specified in fractions of a meter. The most common designation is micrometers or microns. A micron is one millionth of a meter. Most measured particles fall into this range. There are applications in which the particles may be very small, in which they may be specified in nanometers. These applications are usually in the colloid region and are measured with electron microscopes or dynamic light scattering devices
  • Particle size distributions can take on a large number of shapes and sizes. It would be impossible for a practical analyzer design to properly display all of these curves. For this reason, particle size distributions are represented by a series of segments or channels known collectively as a histogram. As shown in the figure, a histogram is a stepwise approximation to a continuous distribution. The number of segments or channels is variable. However, if there are too few channels, the distribution will not be well represented. If there are too many, the data become cumbersome. The number of channels selected then becomes a matter of choice based on design, practicality and aesthetics. Because we have a distribution of sizes, we will need to use several statistical measures to describe the whole. Median, mean, or mode describe the center of the distribution in different ways. Percentiles can be used to define specific points along the distribution. Standard deviation or CV can be used to describe the width of the distribution.
  • Here are additional mean diameters that we can calculate for our simple distribution.
  • Here is the equation used to calculate the D[4,3], which is sensitive to the presence of coarse particles. It may make sense to include this specification if the presence of coarse particles is detrimental to product performance, but be aware each new value included in a specification implies one more way for the product to fail the spec.
  • From this example, we can see that for a non-Gaussian distribution, the mean, median and mode are at different points in the distribution. It is important to realize the differences between these three measures of the center of a distribution.
  • Standard deviation is a statistical measure of the width of a distribution. One standard deviation is the width which contains 68.27% of the total distribution. Two standard deviations contain 95.45% of the total distribution.
  • When setting particle size specifications on drug substances, keep several thoughts in mind. Laser diffraction is inherently a very repeatable technique. If multiple measurements of the same sample generate high RSD’s then work at your sampling, dispersion and standard operating procedures until they reach the ranges suggested in this presentation. You final specifications should be set depending on the product performance, and then tightened to take into account errors from sampling, measurement, etc.
  • Ten (10) bottles of Whitehouse PS202 (3-30um) glass beads added to the LA-950. The percent transmittance of each light source (red laser and blue LED) are shown to illustrate how the LA-950 reports “concentration”. The Verifications were established for D10, D50, and D90 values according to the NIST certification, material uncertainty, and ISO-based instrument tolerance (5, 3, 5%). The D10 values do not pass Verification starting at bottle number 3. D50 falls out of range at bottle number 7.
  • Using the Intensity Graph feature of the LA-950, we can extract the light scattering intensity for each detector angle (i.e. light scattering pattern) used during measurement. All 10 measurements had the light scattering pattern extracted and are graphed here in relation to each other. Typical multiple scattering behavior shows us non-linear increase in scattered light intensity at wide angles (indicated here by increasing detector number). We see that the first two bottles exhibit very similar light scattering patterns and that the dissimilarity increases with added material and increased particulate concentration. Note that the light scattering pattern appears normalized in the top graph (displaying the entire detector range used for measurement). The lower number (i.e. lower angle, larger particle) detectors exhibit smaller light intensity values as concentration increases. This is the behavior we expect. The scattered light that should be hitting these lower number detectors is instead being re-directed (re-diffracted) by additional particles.