Tag Archives: particulate

Particle Size Analysis: A Glossary of Terms

In the fascinating world of particle size analysis, there are many difficult terms that you may need to get to grips with. Here we’ve provided a glossary of terms from Agglomeration through to Zeta Potential — it’s truly an A to Z of particle size analysis.


A jumbled collection or mass of particles that have collected together; furthermore, the collection of these particles is known as “agglomeration”.

Aqueous solubility

Measured by weight, this refers to the maximum percentage of a substance that dissolves in a unit volume of water.


The extent to which a living organism is able to absorb a drug into its systemic circulation. Bioavailability is important in ensuring drugs have their desired effect in the body.


A method of separating a mixture of compounds by passing them through a medium in which the components progress at different rates.

Coarse particle fraction

The percentage of a material which is composed of large particles.

Dose uniformity

The extent to which the active material within a sample of dosage units remains uniform. It is usually expressed as a percentage of the average content.

Hydrodynamic volume

The overall volume of a polymer when it is situated within a solution. The hydrodynamic volume can be measured by the way the polymer behaves in that solution.

Laser diffraction

A technique for measuring particle size which is predicated on the idea that particles moving through a laser beam will scatter light at an angle directly proportional to their own size. Laser diffraction is one of the most effective methods of particle size analysis.


The grinding of materials into smaller particles.


A molecule that consists of just a few repeating units, or monomers, which bind together chemically.


Small subdivisions of matter that can be found suspended in a gas or liquid.


Anything which is administered or absorbed through the skin, such as an injection or transdermal drug.


The state of having a broad range of particle sizes within a semisolid; this stands in opposition to monodispersity, where the particles are all of the same size. Polydispersed materials tend to pack better than monidspersed materials.


A large molecule composed of many repeating units, or monomers, which bind together chemically.


The study of the deformation and flow of matter, usually in reference to the flow of liquids but also sometimes to semisolids.


A naturally-occurring process whereby solid particles settle out of the fluid carrying them and come to rest against a barrier.

Semisolid drug

Otherwise referred to as simply a ‘semisolid’, it’s a pharmaceutical product that has some properties of solids and some properties of liquids. Common examples include creams, ointments or gels.

Shear rate

The rate that contiguous fluid layers move in relation to each other.

Size Exclusion Chromatography

A form of chromatography whereby molecules in a solution are separated based on their varying hydrodynamic volume.

Transdermal patch

A patch which is applied to the body in order to administer a certain amount of drugs through the skin and, subsequently, into the bloodstream.


The resistance that a liquid shows to being deformed by sheer stress.

Zeta potential

The effective charge on a particle that is immersed in a liquid.  This can have a significant effect on the stability of particles in suspension.

Looking for the perfect analytics instrument for YOUR next big discovery?

Speak with the ATA Scientific team today to get expert advice on the right instruments for your research

Request free consultation

10 Benefits of Real-Time Particle Size Analysis

If you’re looking for optimal performance in the particle size analysis process, then real-time or ‘on-line’ particle size analysis methods, such as laser diffraction, are the way to go. There are several applications for real-time particle size analysis, including sticky-wet concentrated slurries, liquid emulsions, and dry particulate streams. With the use of automated on-line analysis, the frequency of measurement increases significantly, enabling a reliable and efficient data stream to be delivered.

Benefits of real-time particle size analysis

There are several benefits that can occur as a result of utilising real-time particle size analysers, outline below.

1. Increased return of investment (ROI)

These online instruments have been shown to be extremely sturdy and capable of providing 24/7 operation with only a small amount of upkeep. You can achieve visible ROI within six to 12 months of operation, with both product quality and plant capacity enhanced by automatic real-time measurement.

2. Lower energy

While milling operations are generally quite energy-intensive, consumption has been shown to see an exponential increase as particle size becomes smaller. Quality control failure can occur as a result of under-milling, while over-grinding can result in too much energy being used. With real-time particle size analysis you will see minimal energy use to create products that meet specifications.

3. Real-time control

From metal powders to pharmaceuticals, particle size is a key performance parameter in a lot of particulate products. Real time particle size analysis, therefore, makes a lot of sense. The on-line systems are capable of measuring up to four particle size distributions per second.

4. Troubleshooting

By utilising continuous measurement, you’ll be able to see the outcome of every variable in real time, which makes troubleshooting a lot easier than viewing these variables with the disadvantage of occasional off-line analysis methods.

5. Increased efficiency

Using off-line analysis to examine process parameters and their effects can be time consuming. With real-time particle size analysis, you’ll be able to evaluate these situations in minutes instead of hours. Causal links become clear at a much quicker rate than normal.

6. More intelligent process development

Since the acquisition of knowledge is the main role of process development, real-time measurement has obvious advantages. Potential problems can be detected at an early stage, speeding up the knowledge gathering process.

7. Quicker product changeover

Since, during changeover, you’ll want to get to the set point as fast as the plant dynamics will allow, on-line systems are definitely the way forward. Waiting on lab results to ascertain whether or not it’s safe to switch to the in-spec collection silo is no longer necessary; instead, you’re fed this information in real time.

8. Immediate upset detection

In general, offline analysis is done on an hourly basis (at most). As a result, any upsets may not be detected for an hour at best and response to upsets may take even longer – enough time to spoil a batch. On-line analysis allows upsets to be detected immediately.

9. Higher sensitivity to quality

Real-time data is sensitive to changing conditions, allowing for tighter process control. Off-line data, on the other hand, is usually an average taken from composite samples, which lacks the sensitivity necessary to spot out-of-spec samples.

10. Reduced operator risk

Occupational health and safety problems can arise during the sample extraction process, especially when materials are highly toxic or volatile. The use of a real-time particle size analyser eliminates this risk.

Find the right product to get the benefits

ATA Scientific offers scientific instruments suited to many scientific endeavours, including real-time particle size analysers. Browse our range of particle science products today to find what you need.

Looking for the perfect analytics instrument for YOUR next big discovery?

Speak with the ATA Scientific team today to get expert advice on the right instruments for your research

Request free consultation