Page 26 - Phytochemistry -1 (PG404) / Clinical Pharmacy 2nd level students ( 2019 )

Clinical pharmacy PharmD program Third level Phytochemistry-1 (PG-504)

Notes:

• Cupper reduction method is a type of reversed titration as:

The burette contains sample instead of titrant

The flask contains titrant instead of sample

• Time of reaction not exceeds 3 min

• Methylene Blue (M.B) is used as internal indicator and the E.P is
reached when the color of indicator disappear

Methylene blue
reduction Methylene blue
oxidized form
reduced form
have blue color
by sugar have no color

• Standard Fehling's solution is made in two solutions: solution A
contains 69.28 gm of pure crystalline copper sulfate in one liter of
distilled water. Solution B contains 350 gm of Rochelle salt and 100 gm

of caustic soda

• For use 5 ml of solution A are mixed with 5 ml of solution B. The

mixture has a deep blue color and is known as Fehling's solution.

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