Gram for microbiology 500 ml

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Product for the preparation of cyto-histological samples for optical microscopy. Differentiation of gram-positive and gram-negative bacteria in fixed smears. This method is often used to assess suitability of specimen for culture.

Gram - positive bacteria and yeast cells retain crystal violet and stain blue. Gram-negative organisms allow crystal violet to wash out in decolourization and subsequently take up counterstain safranin and stain pink.

METHOD:
1) Fix air-dried smears using one of the following techniques: a - Heat fix by passing the slide through a low flame 2-3 times. Cool the slide at room temperature before staining b - Methanol fix, immerse the slide in absolute methanol for 1 - 2 minutes and rinse with distilled water before staining.
2) Cover specimens with reagent A (Crystal-violet Hucker solution), leave to act 1 minute.
3) Drain the slide and flood briefly with reagent B (Lugol solution).
4) Cover completely with reagent B (Lugol solution) and leave to act 1 minute.
5) Wash with distilled water.
6) Cover completely with reagent C (Decolorizing solution): leave to act 1 minute.
7) Wash with distilled water
8) Cover completely with reagent D (Safranin solution): Leave to act 1 minute.
9) Wash carefully with distilled water.
10)Air dry