Blog | Hydrosense

Behind Hydrosense PRO: Making Legionella Testing See More

Written by Ruth Thomas | Oct 13, 2023 4:21:54 PM

Legionella pneumophila (L. pneumophila) serogroup 1 has long been a major focus here at Hydrosense and we are passionate about the part we play in tackling this harmful water contaminant. With most fatal outbreaks of Legionnaires Disease being caused by L. pneumophila sg1 its importance is unquestionable.

However, the presence of other serogroups of L. pneumophila are also frequently being associated with disease across the globe and when they strike, their impact is no less important. Taking this into consideration, we have spent the last four years developing our next generation of rapid technology to quickly and accurately detect not only L. pneumophila serogroup 1, but also serogroups 2-15.

Introducing our Rapid Testing game changing product

Hydrosense PRO is the culmination of the tireless work of the Hydrosense team over these last four years and we are very excited to introduce this brand-new rapid test which has the potential to change the way we approach water safety all around the World.

How did we create hydrosense PRO?

Whilst the test itself may appear to be a simple device, don’t let the ease of use and simplicity of obtaining a test result belie the innovation that went in to achieving Hydrosense PRO. The test, like our flagship Hydrosense ONE test, is based on the well-known Lateral Flow Immunochromatographic Assay (LFICA) technology, an antibody-based test more commonly used in pregnancy or Covid tests. But, although a well-used technology, the ability to detect both L. pneumophila sg1 AND all of the remaining L. pneumophila serogroups 2-15, separately and at a level of sensitivity that matches the legislative needs of various territories worldwide was no easy feat!

Four years of development

Development of Hydrosense PRO required a number of precise stages in order to achieve our ambitious goal. Creating the ideal set of antibodies which targeted L. pneumophila sg2-15 was the first challenge! The antibodies created had to be optimised to ensure that they reacted with ALL the desired serogroups of L. pneumophila at a good level of reactivity but that they didn’t cross react to other species of Legionella or common waterborne bacteria which the test might be exposed to.

Once we had determined that our new sg2-15 antibodies were successful and also that they did not cross react with our antibodies to sg1 (to ensure we could differentiate between these serogroups on the final product) they were purified and coupled to coloured particles (red for sg1 antibodies and green for sg2-15) ready for the next stage in the process.

Construction of the Lateral Flow Test

With our antibodies ready for use, it was time to turn our attention to the construction of the lateral flow test itself. A lateral flow test is composed of a series of membranes which overlap each other on top of a backing card;

  • a sample pad to receive and prepare the sample for processing along the test.
  • a conjugate pad which stores the conjugated antibodies (here the red coloured sg1 and green coloured sg2-15 antibodies)
  • a nitrocellulose membrane, which houses the partner antibodies which allow for creation of test and control lines.
  • an absorbent pad to absorb excess sample.

 

What goes into each of these different membranes on the Hydrosense PRO test is a closely guarded secret by the scientists at Hydrosense but everything involved was rigorously tested to ensure the optimum formulations and the best combinations possible. Once perfected, these membranes were all laminated together before being housed in the signature Hydrosense cassette to create the product you recognise.

Hydrosense PRO: Ready for Action

Finally, in culmination of the four-year development process, a complete validation process was then performed to ensure that Hydrosense PRO met all our stringent specifications and was ready for every challenge that environmental water samples from different sources might throw at them.

The result, when combined with our tailored filtration and concentration step, is a highly sensitive breakthrough test that detects both L. pneumophila sg1 and L. pneumophila sg2-15 at 100 cfu/L on separate test lines of different colours (red for sg1, green for sg2-15) making on-site Legionella testing faster, more accurate and more informative than ever before. We are very proud of this innovation, but don’t just take our word for it, add Hydrosense PRO to your water safety arsenal today and work with us at reducing the risks associated with Legionella pneumophila for everyone.