Particle Characterization

How does particle characterization work?

The standard technique for particle size characterization is Laser Scattering Particle Size Distribution analysis. Laser light is scattered by the particles in a sample, forming a diffraction pattern. Analysis of the scattered light will provide information on particle size, from micrometers to nanometer. A Multi-Laser Nanoparticle Tracking system allows you to acquire data on particle size distribution and particle concentration.

Static (laser or LED) light is used to image particles passing through an optical flow cell. This can also be used to assess particle shape, starting at around 1 micrometer. The particle surface area can be measured acquiring gas adsorption and desorption data of particles with the flowing gas method.

Zeta potential is measured in solution using electrodes, which attract the particles based on their charge. Laser light is used to measure the particle speed at different voltages, from which the zeta potential of the particles can be calculated.

Why use particle characterization?

Many bulk materials are shipped as dry particles, such as ground powders. This is the case for foods, but also for metal powders used in coatings, and polymers for plastics production, to name just a few examples. Pharmaceuticals can be delivered as liquid emulsions. In all these cases, particle characterization is important to monitor quality before these products are used in production.

The wide range of applications and the great diversity in particle systems requires an equally wide range of instruments for particle characterization. ST Instruments offers these instruments, produced by Horiba Scientific. They allow analysis of dry particles or particles in a liquid (emulsions) from the micro- to nanoscale.

Pharmaceutical Development and Quality Control:

In the pharmaceutical industry, particle analyzers play a crucial role in formulation development and quality control. Particle size and shape analysis ensure consistent drug performance by optimizing parameters like dissolution rates and bioavailability. Zeta potential measurements aid in understanding particle stability and aggregation tendencies, critical for developing stable suspensions and preventing sedimentation in pharmaceutical formulations. These analyses help ensure that medications deliver their intended therapeutic effects reliably.

Food and Beverage Industry:

Particle analysis is pivotal in ensuring the quality and stability of food and beverage products. Particle size measurements help optimize product texture, mouthfeel, and appearance, ensuring consumer satisfaction. For instance, controlling the size of emulsifier particles influences the stability and texture of sauces and dressings. Zeta potential assessments are used to prevent the separation of ingredients in products like beverages and salad dressings, ensuring uniformity and prolonging shelf life.

Environmental Monitoring:

Particle analyzers are essential tools for environmental monitoring and assessment. In air quality studies, they provide insights into the composition and size distribution of airborne particulate matter, which can have significant health implications. In water bodies, particle size analysis helps detect microplastics and assess sediment characteristics. Zeta potential measurements aid in understanding particle behavior and agglomeration tendencies, contributing to the study of pollutant transport and deposition.

Biomedical and Life Sciences:

Particle analysis is integral to materials research, especially for nanomaterials. Researchers use these instruments to study the synthesis, behavior, and applications of nanoparticles and nanocomposites. Accurate particle size and shape analysis inform the design of materials with desired properties, such as catalytic nanoparticles or drug delivery carriers. Zeta potential measurements guide the optimization of surface charge for specific applications, like enhancing nanoparticle dispersion or controlling interactions in nanoelectronics.

Environmental Monitoring:

Particle analyzers are valuable tools in biological and medical research. Particle size and shape analysis are used to study cellular morphology, microparticles, and extracellular vesicles. This aids in understanding cell interactions, cellular response to treatments, and disease mechanisms. Zeta potential measurements help researchers investigate cell membrane interactions, nanoparticle uptake, and the stability of biological suspensions such as liposomes used for drug delivery.