Meritics blog expands on the Coulter Principle

Nov. 23, 2012 - PRLog -- In its continuing effort to help match analysts’ needs to the best possible solutions, Meritics has set up a blog site exploring the applications and advantages of Coulter Counters.

As visitors to http://www.coultercounter.co.uk will discover, Coulter Counter analysers offer the most accurate method for sizing particles and – at the same time – assessing their numbers and concentrations.

That’s the message in brief but, given that more than 8,000 references to Coulter Principle technology have been documented to date, there is a lot more to tell.  The new site begins by explaining the technology, its advantages over other techniques, and its applications.  It then goes on to provide further background information and insight to ensure that users make the right choices.

The Coulter Principle works by subjecting particles, suspended in a dilute conducting liquid, to an electric field.  Electrodes are placed on each side of an aperture of defined size, within which the electrical current is physically confined.  The effect of this is to create a vacuum which draws particles through the aperture, one at a time.

In doing so, each particle displaces its own volume of liquid.  Electronic analysis of the pulses generated by this gives high-resolution information on size distributions in terms of number, volume and surface area – all in one measurement.

The essential technique has existed since the late 1940s when Wallace H Coulter, working with the United States Navy, developed it as a quick way of obtaining blood cell counts.

Today over 98% of all automated cell counters rely on the Coulter Principle, but its uses have expanded to the characterisation of such diverse substances as drugs, pigments, fillers, toners, foods, abrasives, explosives, clay, minerals, metals and materials for construction, coatings and filters.

In fact, the coulter counter blog points out that as long as it can be suspended in an electrolyte solution, any particulate material can be analysed in this way.  Coulter Counters will deal with particles anywhere between 0.4 µm and 1600 µm in diameter, providing data on size and concentration quickly, routinely and accurately.

There are, of course, other instruments available for measuring particle size, but it is important to note that those which depend on light scattering measurements, rather than the Coulter Principle, cannot provide data on concentration.  Coulter Counters can also be used regardless of material and particle colour, shape, composition and refractive index.

Coulter Counter® instruments are developed and manufactured by Beckman Coulter® – one of a range of leading particle characterisation instrumentation companies represented by Meritics.

Beckman Coulter offers a range of specialised analysers to meet the varied needs of their users – which are explored further in www.coultercounter.co.uk.  The applications are seemingly endless, but here a just a few recent examples to show their diversity:  large-scale analysis of whole blood;  characterisation of small organisms in sea water;  efficiency testing of filters; research on bacteria;  and counting and sizing studies on protein aggregates, emulsions, dust, contaminants, microbubbles and adipose tissue.

Committed to giving expert and unbiased advice on equipment and techniques, Meritics will be happy to look at any application and advise on which Coulter Counter – or other product – is the answer.  With a range of support services, including a telephone helpline and field-based engineers, Meritics is there to guide users through the selection process.

For further information on Coulter Counters visit http://www.coultercounter.co.uk
To find out more about products and services available from Meritics, go to http://www.meritics.com.