When a harmful algal bloom (HAB) shows up in a lake, reservoir or drinking water source, the first question is whether it is producing microcystins. There are three common ways to answer it: a microcystin ELISA for quantitative lab results, rapid lateral flow test strips for screening in minutes, and qPCR for detecting the genes that make the toxin. This guide compares them so you can choose the right test, or the right combination.
Microcystin test comparison at a glance
| Test | What it measures | Sensitivity | Time to result | Best for |
|---|---|---|---|---|
| Microcystin ELISA Kit (EL2024-02) | Microcystins and nodularins (quantitative) | 0.05 ppb | 75 min incubation | Water, wastewater, algal cultures, fish |
| Congener-Independent Microcystin/Nodularins ELISA (EL2024-05) | Total microcystins and nodularins (quantitative) | 0.15 ppb | 75 min incubation | Drinking and ambient water; compatible for use with US EPA Method 546 |
| Rapid test – Finished Drinking Water | Microcystins (screening) | 0.1 ppb | 15 min | Treated drinking water |
| Rapid test – Recreational Water | Microcystins (screening) | 4 ppb | 10 min | Shoreline testing of lakes, ponds and swimming areas |
| Rapid test – Lab | Microcystins (screening) | 4 ppb | 10 min | Bench screening of water and algal cultures |
| Microcystin qPCR Detection Kit | mcyE toxin-production gene | Gene presence | One qPCR run | Early warning: are toxin producers present? |
When to use a microcystin ELISA
A microcystin ELISA gives you a number, in ppb (µg/L), that you can compare against advisory levels and report. Both of Attogene’s microcystin ELISA kits are competitive immunoassays in a 96-well plate, with six microcystin-LR standards and a 30 + 30 + 15 minute incubation. You read the plate at 450 nm on an ELISA plate reader and fit a standard curve.
- Choose EL2024-02 when you need the lowest detection limit (0.05 ppb) or are testing wastewater, algal cultures or fish tissue. Read the EL2024-02 microcystin ELISA manual (PDF).
- Choose EL2024-05 when you need total microcystins in drinking or ambient water, or are working to US EPA Method 546. A Method 546 supplemental QC pack (EL2024-Q) is available. Read the EL2024-05 total microcystin ELISA manual (PDF).
To run a microcystin ELISA you will also need a plate reader, micropipettes (including a multichannel), deionized water, methanol, a vortex mixer and a timer. See quantifying microcystin in water with an ELISA plate reader for an example setup.
When to use rapid microcystin test strips
Lateral flow test strips answer a yes/no question fast, with no plate reader needed. They are competitive tests: a lighter test line than the negative control means more microcystin. Use them to decide where to sample further, when to post a recreational advisory, or which samples to send for ELISA confirmation.
- At the shoreline: the Recreational Water kit includes bottles, filters and syringes and screens at 4 ppb in 10 minutes.
- At the bench: the Lab kit uses your own pipettor and screens water and algal cultures at 4 ppb.
- At the treatment plant: the Finished Drinking Water kit screens at 0.1 ppb in 15 minutes, below the EPA’s 0.3 ppb health advisory for young children.
When to use microcystin qPCR
The Microcystin qPCR Detection Kit detects the mcyE gene, which cyanobacteria need to make microcystin. A positive result tells you toxin producers are present, often before toxin levels rise, so it works well as an early-warning tool alongside ELISA. It does not measure the toxin itself.
A practical microcystin testing workflow
- Watch: use qPCR or visual bloom monitoring to spot toxin-producing cyanobacteria early.
- Screen: run rapid test strips on site to triage samples in minutes.
- Quantify: confirm positives with a microcystin ELISA to get a reportable ppb value.
Frequently asked questions
Which microcystin ELISA kit is compatible with EPA Method 546?
The Congener-Independent Microcystin/Nodularins ELISA Kit (EL2024-05) is compatible for use with US EPA Method 546.
Can microcystin test strips replace an ELISA?
No. Test strips are screening tests. Results that drive regulatory or public health decisions should be confirmed by ELISA, HPLC or LC-MS/MS.
Can I test fish or spirulina for microcystin?
Yes. The Microcystin ELISA Kit (EL2024-02) includes a methanol extraction for solid samples. See testing spirulina for microcystin for an example.
How long does a microcystin ELISA take?
Incubation totals 75 minutes (30 + 30 + 15), plus sample prep and plate reading.
Not sure which microcystin test fits your program? Call 512-333-1330 or email sales@attogene.com for free technical support. Learn more about microcystin and harmful algal blooms.
