Which item is used to stain Modified Knott's technique?

Which item is used to stain Modified Knott's technique?

• A. Methylene blue stain
• B. 2% formalin
• C. Glass slides
• D. Coverslips

Answer: (A)

Staining in the Modified Knott's technique is done with methylene blue because, after lysing red blood cells with formalin and concentrating the microfilariae, a simple dye is needed to visualize the organisms clearly. Methylene blue provides good contrast and highlights the parasite’s structures under light microscopy, helping you recognize microfilariae by their outline and nuclear features. The other items serve different roles: formalin acts as the lysing fixative, while glass slides and coverslips are for mounting the sample and viewing it—not for staining.

Staining in the Modified Knott's technique is done with methylene blue because, after lysing red blood cells with formalin and concentrating the microfilariae, a simple dye is needed to visualize the organisms clearly. Methylene blue provides good contrast and highlights the parasite’s structures under light microscopy, helping you recognize microfilariae by their outline and nuclear features. The other items serve different roles: formalin acts as the lysing fixative, while glass slides and coverslips are for mounting the sample and viewing it—not for staining.