00:00:00 | Welcome |
00:00:08 | Speaker Introduction |
00:01:18 | How to measure particle size distribution |
00:01:49 | Abstract |
00:02:04 | Overview of Techniques |
00:02:09 | Number/visualization and volume/mass |
00:03:56 | The killer word… |
00:05:23 | How much sample do we need? |
00:06:35 | Before a particle size measurement? |
00:08:57 | Volume-Number |
00:10:44 | Size isn’t everything… |
00:11:46 | What do we ‘see’ with any technique? |
00:12:41 | Orientation of particle |
00:13:17 | The techniques that we’ll consider |
00:13:22 | Why so many techniques? |
00:14:56 | Sieving |
00:15:37 | Grizzly |
00:16:46 | All retained particles are considered the same (> 1”) |
00:17:18 | Sieves |
00:17:48 | Sieves |
00:19:11 | Sieves |
00:19:28 | Sieves |
00:20:59 | Sieving |
00:21:39 | Sedimentation |
00:22:09 | ‘Sample preparation’ |
00:23:41 | Pre-treatment(s) |
00:24:10 | Stokes’ Law |
00:25:31 | Comparison with diffraction |
00:26:04 | Sedimentation |
00:26:59 | Microscopy/Image analysis |
00:27:38 | Microscopy/Image analysis |
00:28:50 | Microscopy/Image analysis |
00:29:10 | ~ 1.7 million particles measured |
00:30:10 | Electrical Sensing Zone or Coulter Counter |
00:31:16 | ESZ - Principle |
00:31:35 | Electrical Sensing Zone - (Coulter Counter) |
00:32:20 | Electrical Sensing Zone - (Coulter Counter) |
00:33:04 | Gas adsorption techniques (BET) |
00:33:38 | Gas adsorption techniques (BET) |
00:33:51 | Gas adsorption techniques (BET) |
00:34:22 | Small-angle X-ray scattering (SAXS) |
00:36:20 | Nanoparticle Tracking Analysis (NTA) |
00:37:37 | Resonant Mass Measurement – Archimedes |
00:38:57 | Light obscuration counters |
00:40:10 | Light scattering |
00:41:13 | Why laser diffraction? |
00:43:32 | Measurement principle |
00:45:13 | 158 yards? Diameter of quarter? |
00:45:46 | J Raymond Hodkinson |
00:46:09 | Horace Edgar Rose (May 30th, 1913 – January 19th, 1999) |
00:47:11 | Halo around moon |
00:47:37 | Size of ice crystals |
00:48:14 | Variation of scattering angle with particle size |
00:49:35 | So what happens when the size gets small? |
00:51:16 | Just one photon….. |
00:51:43 | Particle sizing and Brownian motion |
00:51:43 | Dynamic Light Scattering |
00:52:05 | Correlation functions for different particle sizes |
00:52:39 | Calculating size distributions from the correlation functions |
00:53:21 | This is pretty important! |
00:53:56 | International Standards |
00:54:58 | Bonus slide! |
00:55:10 | Thank you |
00:55:36 | Appendix |
00:55:41 | Appendix |
00:55:43 | Appendix |
00:56:00 | Thank you for your attention |
There is a gamut of particle size distribution measurement techniques each with established history and advantages. The killer word in particle size distribution ids the last one (distribution) and measurement of broad distributions is the bane of all sizing techniques. After a very short introduction to ‘how much sample should we measure to describe the distribution’, we’ll be running through the background of some of the more popular techniques (sieves, sedimentation, electrical-sensing zone) and will emphasize the popular light scattering techniques of laser diffraction and dynamic light scattering. As anaside we’ll be mentioning Small-angle X-ray scattering (SAXS).
We’ll look at counting techniques especially those in the nanotechnology (nanotracking analysis (NTA), resonant mass measurement (RMM)) and regulatory (obscuration counting) arena. In line with the statement in USP <766> Optical Microscopy, “For irregularly shaped particles, characterization of particle size must also include information on particle shape’, we will look at the benefits of high speed image analysis where statistically valid numbers of particles can be counted and measured for both size and shape distribution. We’ll point out 2 international (ISO & ASTM) standards that provide an overview to available methods.