Rapid detection of melamine
Chain stitch is a technique for sewing or embroiding a series of looped stitches, in purpose of forming a chain-like pattern. Thus our Chainstitch Sewing Machine can be simply considered as chain-like stitching machine for industrial sewing applications. Sewing is a very important process in the garment production process. Different sewing patterns are needed to meet different clothing requirements. Chainstitch Sewing Machine chainstitch sewing machine,feed-off-the-arm chainstitch sewing machine,chain stitch sewing machine needles DONGGUAN CHUANGHUI SEWING MACHINE CO.,LTD , https://www.ch-sewing.com
Detection principle: The melamine detection kit is a competitive enzyme-linked immunosorbent assay. Melamine is extracted from the sample. The melamine-HRP, sample extracts and standards were added together to react in the wells coated with melamine antibody. After 30 minutes incubation, the samples were mixed with melamine and melamine-HRP and melamine antibody, and any unbound melamine was found. And melamine-HRP will be washed away, and the chromogenic enzyme substrate will be added to the microwells. Any combined melamine-HRP will make the liquid blue. The reaction was stopped after 20 minutes and read with a microplate reader. Comparing the reading of the unknown sample with the reading of the standard gives the melamine concentration in the sample.
Required equipment and materials for the experiment:
1. Deionized or distilled water (ZealPure)
2.20-200ul single channel micro sample gun (NPX-200)
3.50-20000ul 8-track micro-loading gun (00-NP7-8L)
4. Plate reader (405nm) (BioTek ELx800)
5. The timer (Casio)
6. Wash bottles (Nalgene)
Testing procedures:
1. Recover all reagents to room temperature and wash the bottles with deionized water;
2. Prepare the required microwell strips;
3. Add 100 μL of each standard or diluted sample extract to the indicated wells and add 50 μL of melamine-HRP;
4. Slightly shake for 60 seconds and culture for 30 minutes;
5. Drain the liquid from the hole, add water to the hole with a pipette, and drain the liquid. Repeat the operation 3 times;
6. Add 100 μL of substrate per well;
7. Incubate for 20 minutes;
8. Add 100 μL stop solution to each well;
9. Read at 450nm reader.
Interpretation of results:
1. Semi-quantitative results can be obtained by comparing the absorbance of a sample with the absorbance of a standard. When the color of the sample is lighter than that of the standard, the concentration of melamine in the sample is higher than that of the standard. If the color of the sample is darker than that of the standard, the concentration of melamine is lower than that of the standard.
2. The quantification can be obtained from the standard curve diagram. The absorbance of the sample is used as the X axis, and the logarithm of the standard concentration is used as the Y axis. Y
The corresponding point on the axis multiplied by the corresponding dilution is the concentration of the sample.