The AccuSizer is the cornerstone of the modular family of instruments. All AccuSizer systems measure particle size and concentration using a sensor, counter, and fluidics configuration. A series of sensors based on the single particle optical sizing (SPOS) technique using light extinction, scattering, or in combination are available. The counters are fast, multi-channel pulse height analyzers than can report results in up to 1024 size bins. Several fluidics configurations are available to deliver the sample to the sensor directly or with autodilution to avoid coincidence errors. Particles in a liquid suspension flow through a photozone where they interact via extinction and/or scattering with a laser light source. The extinction/scattering by the particle is related to particle size and concentration through the use of a pulse height analyzer and a calibration curve. The result generated is the concentration and particle size distribution of the particles in suspension.
The AccuSizer Autosampler has been designed to meet the needs of applications where higher throughput or repetitive analyses are required. The AccuSizer Autosampler is compatible with all of the various AccuSizer and Nicomp system configurations, including A7000 series AD (Autodilution), APS (Automatic Particle Sizer), SIS (Syringe Injection Sampler, and the Nicomp N3000 series Dynamic Light Scattering systems. PSS also offers the AccuSizer A7000 Series Autosampler, a standalone sampling system that is available with an integrated SIS, AD, and DI (Direct Inject Sampler) fluidics configurations. All of these systems are controlled by PSS software packages each specifically designed to meet the rigors of the individual fluidics systems and applications that they address.
The AccuSizer Autosampler is engineered using the same modular design approach as our other products providing the flexibility of matching our capability modules to the specific needs of our customer’s applications. The system can be configured with optional single point and multipoint stirring systems that can stir all of the samples simultaneously. An optional Peltier controlled temperature rack is also available for small samples that need to be at a controlled temperature while awaiting analysis.
The AccuSizer Mini is used around the world for online particle size analysis of CMP slurries Let us look at your sample and we will help you select the optimum system configuration specific for your application. The AccuSizer Mini is engineered using a modular design approach that allows us to match sensors and fluidics options to customer slurries and process equipment. Many samples can be measured continuously without dilution, see Figure 1 below. Some samples require dilution for maximum sensitivity to large particle counts (LPC). A variety of custom, patented autodilution modules assure that the perfect sample state is delivered to the sensor for measurement. A range of sensors operating at focused size ranges and concentration limits utilizing the Single Particle Optical Sizing (SPOS) technique provide the highest accuracy results. The pulse height analyzer generates high resolution results in up to 512 size channels - including up to 32 user defined size channels so customers can report results at their preferred specification points. The system is controlled by a built-in Windows touch PC.
The AccuSizer Mini generates the highest accuracy and resolution results quickly, and at count rates higher than any other technology. This creates LPC and tail results with the best statistical accuracy - detecting the few large particles that will hurt your yield rates, see Figure 2 below with LPC concentration levels near 1 million/mL during a pump failure.
The AccuSizer FX Nano SIS system is specifically designed to measure protein aggregation. The instrument meets and/or exceeds all requirements described in USP <787> Subvisible Particulate Matter in Therapeutic Protein Injections. The results generated include particle size and concentration from 0.15 – 150 µm – covering the official 10 & 25 µm sizes, but with the sensitivity to investigate the more interesting submicron region.
The new AccuSizer FX Nano SIS system consists of:
This unique system utilizes the most advanced light extinction/scattering sensor technologies available to generate particle size and count data at smaller particle sizes and higher concentrations than any other system available. Size distributions are reported in up to 64 size channels.
Particle count data for IgG with no stress (black), 1 hour (red) and 6 hours (blue) stressed at 37o C
The large research effort in nanotechnology over recent years has brought to the forefront the lack of easy-to-use tools for characterizing nanoparticles. While there are several established techniques in the field of particle sizing that can be used to measure the particle size distributions of nano-dispersions, few of them can provide quantitative information in the range of 0.1 to 1 microns. As it turns out, there is a great need for this information. For example, this size range corresponds to where protein aggregates are expected to be, which is of interest to pharmaceutical companies that formulate protein-based drugs because of the safety and efficacy issues posed.Recently, SPOS technology has undergone a quantum leap in capability with respect to the lower size limit of single-particle detection and sizing. Based on a new and innovative approach that uses a focused laser beam to achieve a much smaller and more intensely-illuminated view volume, this new FX-Nano technology can count and size particles as small as 150 nanometers. Importantly, the FX-Nano sensor functions at much higher particle concentrations than those allowed by traditional SPOS sensors – above 1,000,000/mL. As a result, little or no dilution is required for most protein suspensions of interest. SPOS technology made it possible over the years to quantify oversized particles found in many types of dispersions, allowing manufacturers to improve products as diverse as IV emulsions and microprocessors. The new innovation presented by the FX-Nano means that tails of much smaller nanoparticles can be characterized which will lead to the introduction new and improved protein drugs and therapies. This is an ideal system to quantify the size and concentration of aggregated protein.
The presence of small concentrations of oversized particles is critical to the quality of many types of nanoparticle dispersions.
Oversized particles can signal that a dispersion is unstable or that it will clog filters .Using the Accusizer 780 AD or the 780 APS, the determination of oversized particle concentrations in the quality control lab can be performed. A failed product will have to be returned to the factory floor for further processing or junked. In either case, time and money are lost. A more efficient approach would involve in-process monitoring using the 780 OL system. The 780 OL comprises of a range of tools for a variety of in-process and online applications.
These 780 OL systems represent a range of Autodilution fluidics which can be chosen for optimal measurement of your samples. 780 OL systems can be used to monitor processes from homogenization to grinding to semiconductor CMP polishing . The newest addition to the 780 Online family, the 780 POU Point-of-Use monitor, is a small inexpensive unit that can be used for applications that require little or no dilution. So in addition to having systems that can handle concentrated dispersions like emulsions or inks , the 780 POU adds the monitoring of contamination which will have a big impact on pharmaceutical PAT .