Development of a quantitative lateral-flow immunoassay for the detection of

deoxynivalenol in cereals

About deoxynivalenol 2

• Fusarium spp. (mainly F. graminearum and F. culmorum)

WHO

• 15 – 30 °C, water activity > 0.85

WHEN

• Cereals (mainly wheat, durum wheat, barley, maize and their derivatives)

WHERE

• Human gastroenteritis with nausea, diarrhea and vomiting. • The toxicity in animals is reflected by feed refusal and growth retardation.• All animal species are susceptible (pigs > mice > rats > poultry ≈

ruminants).

WHAT

Screening techniques3

Lateral flow immunoassay

ELISA

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Lateral flow immunoassay4

Lateral flow immunoassays are tests based on a kind of immunochromatography. All reagents are generally inside the device and this makes the test suitable to be performed by almost everyone, everywhere.As the sample is loaded on the sample pad, it migrates toward the conjugate pad, where it dissolves the tracer, an anti-deoxynivalenol antibody colloidal gold conjugate. Thanks to capillarity, the liquid flow migrates through the membrane, reaching the immunoreactive lines. On the Test (T) line a conjugate is absorbed. This is a competitor to the free deoxynivalenol molecules eventually present in the sample. The other line is the Control (C) line, where anti-species secondary antibodies are adsorbed and which represent the positive control of the assay. In case the control line would not be coloured, at the end of the assay time, the test is to be considered invalid.

Why?5

For these reasons, in the TWENTIETH year of activity, Tecna launches a new line of immunochromatographic fast screening tools of the detection of mycotoxins in cereals.

Lateral flow devices are hence characterized by fastness and ease of use.

They don’t need many dedicated laboratory equipments. They are a good option for factories, plants and small industies with

low throughput analysis.

is now avaliable on the market for the QUANTITATIVE detection of deoxynivalenol (vomitoxin) in cereals

The test kit

Kit insert

Dilution buffer

Pouches containing the strips

Barcode Businesscard

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Product presentation

Assay principle: competitive lateral flow immunoassay for the quantitative detection of deoxynivalenol

Applications: cereals Measuring range: 500 - 12500 ppb Assay time: 10 minutes Sample preparation: water extraction, centrifugation, dilution

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Sample preparation

Weight 5 g of ground sample

and add deionized or distilled water

Shake thoroughly for 3 minutes

Allow sample to settle down

Centrifuge the upper phase 1

minute

Dilute with the provided dilution

buffer

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Assay implementation9

Pipet the diluted extract in the sample

well

Wait for 10 minutes

Put the developed cassettes in the reader

The reader10

LAB LFD READER

• Multiplex laboratory reader• Ideal for testing more samples together• Ideal for using different assays per time• Up to 5 different assays can be read at

a time

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The quantification depends on the ratio of the colour intensity of the TEST LINE (T) and the CONTROL LINE (C).

The T/C value is interpolated by the reader onto a MASTER-calibration curve that is uploaded with a barcode businesscard for every kit batch.

The Control line must be developed and homogeneous, otherwise the test is invalid

Both readers are able to verify wether the assay is compliant or not

Results achievement

No interpretation mistakes or doubtsValidation

Specificity 100%: no compliant samples are detected as positive

Sensitivity 100%: all > 500 ppb samples are detected as positive.

Remarks: why SMART STRIP DON

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# Plastic cassettes provide high manageability of the devices. A lot of room is available to write the name or the code of each sample, thus ensuring its traceability.

# The sample preparation is dramatically easy: no solvent, incubator, vortex is necessary.

# There are no reagents to prepare and mix, no strip to cut or dry: the sample extract is ready to be dropped on the sample pad. The reaction is incubated 10 minutes at room temperature.

# The LAB LFD READER allows to save time when more samples are run together

Appendix13

Other analytical methods can be chosen to have different performances

ELISAs are now available in different formats

1. Master-curve calibrated, the most cost effective layout, ideal for those implementing a few samples

2. Fast, single replicate layout: 15 – 20 minutes assays

3. Double replicates, to have higher accuracy, reliability and precision

Contacts14

Visit our website www.tecnalab.com

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Contact ou salesteam at export@tecnalab.com