Instructions for Use

1 Principle and Use of Colloidal Gold Detection Card

This product applies the principle of competitive inhibition of colloidal gold immunochromatography for the detection of insecticidal urea residues in vegetables and fruits. After the sample solution is dropped into the sample well of the detection card, the insecticidal urea in the sample solution is combined with the gold standard antibody, thereby preventing the gold standard antibody from binding to the insecticidal urea conjugate on the cellulose membrane. The detection result is judged by the color depth of C and T lines.

2 technical indicators, the minimum detection limit: 0.2 mg/kg (ppm)

3 You need to bring your own tools

Electronic balance, scissors, forceps, disposable cups, vortex mixer, pipette (0.1-1 ml), timer.

4 sample pretreatment

(1) The sample needs to be restored to room temperature (20-30 ° C) before testing.

(2) Take an appropriate amount of sample, cut about 1 cm square, weigh 1 gram of shredded sample in a 5 ml detection tube, add 1 ml of dilution, fully shake for 2 minutes, let stand for 1 minute, to obtain the sample liquid;

(3) Take a 1.5 ml centrifuge tube, the sample liquid and the deworming urea dilution were diluted in different proportions in the following table, and the diluted solution was the liquid to be tested;

According to different residue limit requirements, the above sample treatment solution was processed according to the following scheme:

Detection limit

Sample treatment solution

Deworming urea dilution

Leafy vegetables, orange, pomelo, pear, radish (1000ppb)

50 µL11727798400µL

Kale, cabbage (2000ppb)

50 µL

450µL

5 Sample detection 117277984 Packing bag, take out the detection card/gold standard micropores/dropper (a total of 3 kinds of consumables), and put it on a flat and clean countertop.

(2) Use a pipette or an aluminum foil bag to absorb the above-mentioned dropper 120 µL (about 4 drops) of the liquid to be tested in the gold standard micropores, blow with the dropper until the purplish-red substance in the pores is completely dissolved, let stand horizontally, and wait for the reaction for 2 minutes; Add all the liquid in the gold standard micropores dropwise to the sample hole (S) of the detection card;

(3) Start timing after adding the sample, leave it at room temperature for 8-10 minutes to judge the result, and the interpretation at other times is invalid.

6 result judgment

Negative (-): The color development of the T-line is darker than that of the C-line or there is no significant difference from that of the C-line, indicating that there is no substance to be tested in the sample or its concentration is below the detection limit.

Positive (+): The color development of the T-line is significantly weaker than that of the C-line or the T-line does not develop color, indicating that the concentration of the substance to be tested in the sample is equal to or higher than the detection limit.

Invalid: No C-line appears, indicating that the operation process is incorrect or the test card has failed. In this case, the instructions should be read carefully again and re-tested with a new test card.

7 Note

(1) Products that have expired or the aluminum foil bag is

(2) When the test card is taken out of the refrigerator, it should be restored to room temperature and opened. The opened test card should be used as soon as possible to avoid failure.

(3) Do not touch the white film surface in the center of the test card.

(4) The liquid extraction dropper cannot be mixed to avoid cross-contamination.

(5) If you need to directly test the standard product, please prepare it with the dilution provided in the kit.

8 Storage and shelf life

(1) Storage conditions: 4-30 ℃ Store in the dark, do not freeze.

(2) Shelf life: 1 year, see the outer packaging for the production date.

9 kit composition

specification

composition

10 times/box

20 times/box

test card (containing gold standard micropores, dropper, desiccant)

10 parts

20 parts

deworming urea dilution

1 bottle

2 bottle

5 ml test tube

10 pieces

20 pieces

1 0.5 ml centrifuge tube

10 pieces

20 pieces

manual

1 parts

1 parts