Nitrate rapid test box in food Instructions

Product number: YPHM-04

1 Introduction

Common nitrates include sodium nitrate, potassium nitrate, ammonium nitrate and nitrate converted from agricultural nitrogen fertilizers. In some areas, due to the application of nitrogen fertilizers all year round, the content of nitrate in vegetables, fruits and livestock feeds is high. Data show that nitrate itself is not very toxic, but after entering the human body, it will be transformed into some nitrites or amines due to the action of intestinal bacteria, which pose a hazard to the human body.

2 the detection principle, nitrate in food reacts with color reagents to generate colored compounds. Visual colorimetric analysis is used to compare with the color card in the nitrate kit to determine whether it contains the substance to be inspected.

3 Detection range, drinking water, vegetables, fruits, etc.

4 Technical indicators, detection limit: 10 mg/L

5 sample Determination

5.1 Drinking water: Take 1.0mL of sample directly into the detection tube, shake to dissolve the reagent, let stand for 30 seconds and compare with the colorimetric card, take the same or similar color scale The indicated value is the nitrate content in the sample (in N).

5.2 Vegetables and fruits: Weigh 1.0g of the crushed or mashed sample into a 10ml centrifuge tube, add purified water to a 10mL scale line, and let stand for 5 minutes after sufficient shaking.

take 1mL of supernatant or filtrate to measure (if the sample solution has color, you can add an appropriate amount of activated carbon to shake and decolorize) to the detection tube, shake to dissolve the reagent, and let stand for 30 seconds. After comparing with the colorimetric card, take the same or similar color scale marked on the content of 44.3, which is the content of nitrate in the sample (in terms of nitrate).

* The nitrate limit index of some foods is calculated as NaNO3, and the reading result is multiplied by 44.3 and then multiplied by 1.355.

5 Milk sample: Take 1.0 mL of sample to the detection tube, shake the reagent to dissolve, and let stand for 30 seconds. Compared with the colorimetric card, since the emulsion has nearly 1 times the refractive index, take the same or similar color scale indication value multiplied by 2 is the content of nitrate in the sample (in N).

6 Note

6.1 The sample contains nitrite will form a positive interference. When it is suspected that the sample may contain nitrite, the sample can be measured with a nitrite rapid test tube. The total amount measured with a nitrate rapid test tube minus the content measured by the nitrite rapid test tube to obtain a single nitrate content.

6.2 Nitrate is often present in drinking water and should not be used as a diluent for determination. Purified water or distilled water should be used.

6 If the test results exceed the highest value on the colorimetric card, or the sample absorbs a large amount of water and does not absorb the supernatant, the dilution water can be increased, and the dilution multiple can be multiplied when calculating the results.

6 This product is only used for initial screening, and the final results are subject to the relevant national standard methods.

7 Storage conditions and valid period

Reagents are stored in a cool and dry place at 4-30 ° C, protected from light, and the valid period is 12 months.

8 Product composition

Serial number

Specifications

Composition

10 times/box

50 times/box

100 times/box

1

1 5 ml detection tube

10

50

50

100

2

10 ml centrifugal tube (recyclable)

2

10

20

3

1 ml straw

10

50

100

4

color card

1

1

1

5

manual

1

1

1

1