3 Cadmium chloride--solution C.
Cadmium chloride (c.p.)............................... 10.0 gm
Distilled water .............................................. 100.0 ml
Mix the powder with the water and shake well. Store in a
stoppered brown glass bottle.
(b) Working solution.
Stock Sudan III (Solution A) .............................. 20.0 ml
Stock Methylene Blue (Solution B) .................... 30.0 ml
Stock Cadmium chloride (Solution C) ............... 50.0 ml
STEP 1: Mix solution A with solution B.
STEP 2: Add solution C to the above mixture.
STEP 3: Gently shake for 15 to 20 minutes until a flocculent precipitate develops and
the fluid becomes almost colorless.
STEP 4: Filter and remove all excess liquid from the precipitate by placing the filter
paper with the precipitate upon several layers of dry filter paper. Leave
overnight.
STEP 5: Transfer precipitate to a fresh filter paper and pour it over 25 to 30 milliliters of
distilled water to wash the precipitate.
STEP 6: Dissolve the washed precipitate in 250 milliliters of distilled water.
STEP 7: Filter in a few days if fine crystals of cadmium chloride precipitate out.
STEP 8: Store in a stoppered brown glass bottle.
(c)
Procedure.
STEP 1: Apply a large drop of Quensel's solution to the center of a 25 by 75 millimeter
slide.
STEP 2: Use an applicator stick to pick up a small amount of fecal sample and
thoroughly comminute with the drop of Quensel's.
STEP 3: Apply a 22 by 40 millimeter coverslip to the suspension and seal the edges
with a melted 1:1 vaseline/paraffin mixture.
MD0841
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