Test Principle
Aqua Screen® is a test system for the qualitative or quantitative detection of water pathogens like legionella. Aqua Screen® combines the water filtration, lysis of the collected microorganism, as well as the ex­traction, purification and elution of the DNA in minimal volumes for the subsequent PCR analysis.

Step 1: Preparation of the Sample Material
Drinking water, condensed water from cool­ing systems, bathing or pool water, and waste water released from suspended particles can be used as sample materials. The sample conditioning affects the reliability of the test findings and must be in accordance with the guidelines of the ISO Norm 11731/11731-2. Preservation with chemical or physical means is not possible as intact microorganisms are needed for the filtration procedure.
With suspended particles or fixed volatile contents, contaminated water samples can be purified by prior filtration with a paper folded filter. The samples may not be centrifuged for purification. For the testing procedure, at least 100 ml is minimally required, however a sample volume of 1000 ml is recommended for highest sensitivity.
Free DNA of dead and already lysed legionella in the sample pass through the mem­brane filter and are not detectable in the test system. The test detects both “viable and culturable” and “viable but not culturable” (VBNC) legionella.

Step 2: PCR Application
The Aqua Screen PCR assay is a test for the qualitative or quantitative detection of Legionella spp. or Legionella pneumophila. The test is based on the polymerase chain reaction. Detailed studies confirm the high specificity and sensitivity of Aqua Screen®. The selected template is highly preserved within the species. Cross reactivity with oth­er species typical for water contamination is not known.
By using the supplied internal control, false negative results (e.g. due to inhibition of the reaction by the sample matrix) can be excluded individually for each sample. The detection limit of the PCR step is approximately 2 genome equivalents and the quantification limit for environmental samples is 150 genome equivalents per 1000 ml sample volume.

Detection of Legionella species
The supplied primer set is specific for a segment of the 16S rRNA coding region of the legionella genome. When using the Legionella spp. detection kit for conventional PCR, the amplified PCR product is 244 bp long and can be rendered visible directly in the agarose gel. The qPCR variant is designed such that the specific target probe fluoresces at 520 nm. The conventional PCR internal control amplicon is 150 bp in size. The qPCR internal control is detected by another probe emitting fluorescent light at ~610 nm (Type 1) or
~560 nm (Type 2).
Clinically relevant species that are detected include L. pneumophila SG 1-14 and SG 16, L. longbeachae, L. dumoffii, L. bozemanii, L. gormanii, L. anisa, L. cherrii, L. parisiensis, L. tucsonensis, L. wadsworthii.

Detection of Legionella pneumophila
The supplied primer set is specific for a segment of the mip region of the Legionella pneumophila genome. When using the Legionella pneumophila Detection Kit for conventional PCR, the amplified PCR product is 275 bp long and can be rendered visible directly in the agarose gel. The qPCR variant is designed such that the specific target probe fluoresces at 520 nm. The conventional PCR internal control amplicon is 191 bp in size. The qPCR internal control is detected by another probe emitting fluorescent light at ~610 nm (Type 1) or ~560 nm (Type 2).

 

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Aqua Screen® Fast Extract
Rapid DNA Extraction from Water Samples

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Cat.-No. 32-1010              Aqua Screen® Fast Extract for 10 extractions
Cat.-No. 32-1050              Aqua Screen® Fast Extract for 50 extractions
Cat.-No. 32-1200              Aqua Screen® Fast Extract for 200 extractions

Description
Aqua Screen® Fast Extract can be used with your established suction device (47 mm frittes) for the extraction of legionella and other microbial contaminations. Aqua Screen® Fast Extract is optimized for high flow and throughput and provides high quality DNA for subsequent PCR analysis.

 

Very sensitive Detection accomplished with less than 500 legionella particles per sample volume of 1000 ml.   Ease of use Sample preparation includes simple water filtration and DNA extraction prior to direct PCR analysis. Fast The fast extraction procedure in combination with the rapid PCR method allows detection of patho genic organisms (including those that may be non culturable) in industrial and environmental water samples within a few hours.   Recognizes VBNC (Viable But Not Culturable) Detects both culturable and non-culturable legio nella.   Reliable The extraction kit contains only high quality pro ducts, including amongst others membrane filters, spin columns and buffers. All components have been pre-tested for legionella contamination.   Convenient The Aqua Screen® DNA extraction procedure is very simple and represents an inexpensive method to obtain suitable template DNA for routine PCR tests.

 

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Aqua Screen®
PCR Detection Kits

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Legionella in general:			Legionella pneumophila only:
for conventional PCR			for conventional PCR
Cat.-No. 33-1025	25 reactions		Cat.-No. 34-1025	25 reactions
Cat.-No. 33-1100	100 reactions		Cat.-No. 34-1100	100 reactions
Cat.-No. 33-1250	250 reactions		Cat.-No. 34-1250	250 reactions
for qPCR Type 1			for qPCR Type 1
Cat.-No. 33-2025	25 reactions		Cat.-No. 34-2025	25 reactions
Cat.-No. 33-2100	100 reactions		Cat.-No. 34-2100	100 reactions
Cat.-No. 33-2250	250 reactions		Cat.-No. 34-2250	250 reactions
for qPCR Type 2			for qPCR Type 2
Cat.-No. 33-4025	25 reactions		Cat.-No. 34-4025	25 reactions
Cat.-No. 33-4100	100 reactions		Cat.-No. 34-4100	100 reactions
Cat.-No. 33-4250	250 reactions		Cat.-No. 34-4250	250 reactions

 

Aqua Screen® PCR Diagnostic Kits are used for DNA samples prepared by using the Aqua Screen® Fast Extract procedure. All detection kits for qPCR are AFNOR XP T90-471 compliant. For qPCR two formats are available depending on the qPCR machine being used.
Kit Components

• primer sets and nucleotides at optimized concentrations
• internal amplification control
• positive control for easy result
• verification
• instruction manual

 

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