In Gomori Methenamine Silver staining, the fungi appear red color. What is the cause?

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Multiple Choice

In Gomori Methenamine Silver staining, the fungi appear red color. What is the cause?

In Gomori methenamine silver staining, fungal walls are impregnated with silver to produce a dark deposit that stands out against the background. After silver impregnation, gold chloride toning is used to adjust color and contrast by exchanging some of the silver for gold. If toning is taken too far, more silver is replaced by gold, shifting the color from black toward brownish-red. That’s why fungi can appear red when toning with gold chloride is excessive. The other factors would either preserve the black color (less or shorter toning in gold chloride, or more silver deposition) or weaken the signal (insufficient time in silver), but they don’t produce the red shift seen with over-toning.

In Gomori methenamine silver staining, fungal walls are impregnated with silver to produce a dark deposit that stands out against the background. After silver impregnation, gold chloride toning is used to adjust color and contrast by exchanging some of the silver for gold. If toning is taken too far, more silver is replaced by gold, shifting the color from black toward brownish-red. That’s why fungi can appear red when toning with gold chloride is excessive. The other factors would either preserve the black color (less or shorter toning in gold chloride, or more silver deposition) or weaken the signal (insufficient time in silver), but they don’t produce the red shift seen with over-toning.

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