Starch is a white amorphous powder, and the water-soluble amylose is curled into a spiral shape by hydrogen bonds within the molecule.If the iodine solution is added, the iodine molecules in the iodine solution will be embedded in the voids of the helical structure and linked with amylose by means of van der Waals to form a complex.This complex is able to absorb visible light except blue light more uniformly (wavelength range of 400~750nm), so that the starch solution appears blue.Proteins react with iodine and potassium iodide solution in yellow. Iodine can replace one or two hydrogens at the hydroxyl position of the tyrosine benzene ring on the peptide chain, making it a polypeptide chain containing iodinated tyrosine, showing yellow.

Lodine-potassium iodide solution can stain starch blue and protein yellow, and is also an important reagent for plant histochemical identification.

Usage:
 

At the same time, the starch granule and cell wall of the plant were stained

1. The paraffin section was dewaxed to water, the tissue was cirked with histochemical strokes, and an appropriate amount of iodine-potassium iodide solution was dropped and stained on the tissue for 5min

2. The slices were immersed in 2 tanks of tap water for quick soaking and washing, 2s for each. The slices were immersed in 2 tanks of anhydrous ethanol for quick dehydration, 10s for each

3. The sections were directly immersed in plant solid green dye for 10s, and then put into 3 vats of anhydrous ethanol for rapid dehydration, 10s each.

4. Sections were added into nbutanol for 1min, xylene was transparent for 5min, neutral gum was sealed, and the experimental results were immediately taken for preservation to prevent fading.

Only plant starch granules were dyed

1.  The paraffin section was dewaxed to water, the tissue was cirked with histochemical strokes, and an appropriate amount of iodine-potassium iodide solution was dropped and stained on the tissue for 10min.

2. Pour the dye solution, quickly wash the slices with water, immediately shake the water on the slices, and bake in the oven at 60ºC for half a day

3. Slice into clean xylene transparent for 3min, and then seal the slices with neutral gum. Take photos immediately to preserve the experimental results to prevent fading.

Stain starch granules and protein granules at the same time: (tissues with high protein content, e.g., soybeans)\

After the iodine - potassium iodide solution was dropped on the tissue for 2min, the cover glass was directly placed on the dye solution to seal the tissue. There was no bubble on the tissue. The filter paper was used to absorb the overflowing dye around the glass slides, and the experimental results were immediately taken for preservation.

Staining result:

Starch granules are blue or blue-black, protein granules are yellow, and cell walls are green

Storage and transportation: Storage and transportation at room temperature; iodine-potassium iodide staining solution should be sealed and stored in the dark, and the validity period is 12 months.

1. At the same time for the identification of starch grains and proteins, can not be dehydrated seal, can not be baked dry seal, dyed color will fade, can only be immediately photographed.

2. Please tighten the bottle cap in time after using the reagent to prevent belongings.

3. Please wear lab clothes and Yueyue gloves during operation.