Protocol – Preparation of Gelatin/Chrome Alum-coated Slides for Histological Tissue Sections

Gelatin/Chrome Alum coating helps the slide hold the histological sections firmly, thus reducing the risk of losing histological sections while washing and treatment during staining.

REQUIREMENTS:

Reagents and solutions:
♦ Chrome alum-gelatin solution (0.05% chrome alum, 0.5% gelatin in water)

Equipment and disposables
♦ Histological slides 
♦ Slide racks 
♦ Staining dish

Objective: 
Preparation of Gelatin/Chrome alum-coated Slides for Histological Tissue Sections

PROCEDURE

Step 1: Depending on the requirement, prepare an appropriate volume of Chrome alum-gelatin solution.
To prepare 1L Chrome alum-gelatin solution, dissolve 5 g Gelatin (Type A, 275 bloom, Fisher G8-500 or equivalent)  and 0.5 g Chrome alum (CrK(SO4)2.12H2O) in 1 L warm water (≈ 50 °C). Please click here for detailed protocol.

Step 2: Treat slides with Chrome alum/gelatin solution
♦ Immerse slides into Chrome alum/gelatin solution 4 – 5 times (≈ 5 sec each)
♦ Drain out all excess solution from the slide by gently tapping against the paper towel.

Tip:
◊ If you have many slides (full box), arrange them into slide racks and then immerse them into gelatin solution. 

Precaution:
◊ All slides used for coating should be thoroughly cleaned.

Step 3: Dry all coated slides at room temperature for 2 days.

Precaution:
While drying, protect them from dust.

Storage:
You can store the coated slides at room temperature or -20 or -80°C.