The Attogene Fluorescent Universal Lateral Flow Assay Kit (Europium), AU2049, is a ready-to-use europium lateral flow assay kit for quick, cost-effective development of fluorescent dipstick assays that detect labeled DNA and RNA products. Each kit includes 50 pre-made 4.5 mm dipsticks, nuclease-free running buffer, labeled control nucleic acid and a 96-well plate.
Detection uses europium-dyed polystyrene beads conjugated to streptavidin, with a UV excitation range of 300 nm to 400 nm and emission at 610 nm. Strips can be read by eye with a black light (UV flashlight) or quantified in a fluorescent lateral flow reader. Fluorescent lateral flow assays have been described as 2 to 100 times more sensitive than gold-based tests.
Key Features
- Universal format: Detects amplified DNA products from PCR, LAMP and RPA reactions, or any nucleic acid carrying biotin plus a second label.
- Europium detection: Streptavidin-conjugated europium beads with 300 to 400 nm excitation and 610 nm emission.
- No striping required: Capture lines are pre-sprayed, so there is no need to stripe capture antibodies.
- Multiplex options: Available in 2-line, 3-line and 4-line configurations.
- Low equipment cost: A black light is enough for visual reads; a reader adds numerical output.
- Cost-effective screening: A practical way to screen designs before downstream lateral flow assay development.
What’s in the Europium Lateral Flow Assay Kit
Each europium lateral flow assay kit includes:
- 50 fluorescent lateral flow dipsticks, 4.5 mm (room temperature)
- 12 mL Nucleic Acid Lateral Flow Running Buffer, nuclease-free (room temperature)
- 20 µL control nucleic acid containing biotin and FAM (all versions; refrigerate or freeze)
- 20 µL control nucleic acid containing biotin and DIG (3-line and 4-line versions)
- 20 µL additional control nucleic acid for the 4-line version
- One 96-well plate and manual
Store the kit at 2 °C to 30 °C. Strips are supplied in a plastic canister with integrated desiccant; keep it sealed until use.
You will also need: a timer, a centrifuge for preparing clear specimens, a pipettor and tips, tubes or microtiter plates, and your molecule of interest labeled with biotin plus FITC/FAM, DIG or DNP (depending on version).
Line Configurations
- 2-line (01 version): Test line anti-FITC/FAM; control line biotin.
- 3-line (02 version): Test line 1 anti-FITC/FAM, test line 2 anti-DIG, control line biotin.
- 4-line (03 version): Test line 1 anti-DNP, test line 2 anti-FITC/FAM, test line 3 anti-DIG, control line biotin.
When generating products by amplification, design primers so the final product carries both biotin and the test-line label.
Who It’s For
This kit is for researchers and assay developers who want high-sensitivity fluorescent readout of nucleic acid amplification without striping or cutting equipment. It is a strong fit for labs that already use or plan to use a europium-optimized fluorescent reader, teams pushing detection limits for PCR, LAMP or RPA products, and developers comparing fluorescent labels before committing to a custom design.
How to Use the Europium Lateral Flow Assay Kit
- Add 200 µL of Nucleic Acid Lateral Flow Running Buffer to a well of the 96-well plate.
- Set up sample, positive and negative wells. For samples, add 1 to 5 µL of product as a starting point (try large dilutions on a first run and keep the volume below 15 µL if possible). For the positive control, add 5 µL of control oligonucleotide. Leave the negative control well with buffer only.
- Mix each well completely by pipetting up and down several times.
- Add one dipstick to each well, arrows facing up.
- Incubate for 15 to 30 minutes.
- Read immediately by eye under a black light or in a fluorescent lateral flow reader. Test line signal can diminish quickly once strips are removed from the well.
See the AU2049 kit manual (PDF) for full instructions.
Sensitivity With a Fluorescent Reader
In an Attogene technical article, AU2049 strips read on a Lumos Diagnostics Leelu fluorescent reader detected roughly 60 attomoles of biotin/FAM dual-labeled control oligonucleotide in a titration from 4 femtomoles down to 62.5 attomoles. In the same study, europium gave slightly better sensitivity than the quantum dot and phycoerythrin versions on a reader designed for europium optics. Read the attomole detection technical article (PDF).
Reading Results
The higher the concentration of labeled nucleic acid, the brighter the test line compared with a buffer-only strip. Free streptavidin particles bind the biotin control line, so control line intensity decreases as test line intensity increases, which allows ratio analysis. If no test line appears, a serial dilution may be needed because of the hook effect. Positive samples can be confirmed by agarose or acrylamide gel analysis.
Frequently Asked Questions
How does this compare with the quantum dot and gold versions?
The format and line layouts match the quantum dot Fluorescent Universal Lateral Flow Assay Kit and the gold Universal Lateral Flow Assay Kit; only the detection particle and readout differ.
Do I need a reader?
No. The europium lateral flow assay kit can be read by eye with a black light, but a fluorescent reader is needed to reach the higher sensitivity described in the literature.
How long should I incubate?
The manual specifies 15 to 30 minutes. The positive control should show test and control line signal within 15 minutes.
Why should I read strips right away?
Test line signal can fade rapidly after the strip is taken out of the well, so immediate analysis gives the best readout.
Can the europium lateral flow assay kit be customized?
Yes. It can be configured with alternative or custom streptavidin fluorescent particles and other line layouts. Attogene also offers custom lateral flow assay development services.
For research use only. Not for use in diagnostic procedures. Questions? Call 512-333-1330 or email sales@attogene.com.
