Procedure IV

For the following Drugs:

Disofenin
Mebrofenin

Materials needed:

*ITLC-Silica Gel Strip
*ITLC-SA Strip
*20% Saline
*Purified Water
Scissors
Pencil/Pen
Counting tubes/vials
MCA or SCA or Scaler with scintillation well

*Alternative media and solvents may be suitable. Use of other solvents and medium must be validated before routine use.

Procedure:

1. SeeĀ General QC Procedure. Spot the sample 1 cm from the end of each strip.

2. To develop the strips, place the ITLC-SA strip in 20% saline and the ITLC-SG strip in purified water.

3. Allow the solvent to migrate to the ink spot/line at top of the strips.

4. Remove strips from solvents.

5. Cut each strip at cut line above origin.

6. Count each section of both strips, keeping track of which section belongs to which solvent.

Counts:

Strips:

20% saline:
Top: Free Tc-99m
Bottom: Tagged drug and hydrolyzed-reduced Tc-99m

Water:
Top: Free Tc-99m and tagged drug
Bottom: hydrolyzed reduced Tc-99m

20% saline: % free Tc-99m = (top counts)/ (bottom counts + top counts) X100

Water: % HR Tc-99m = (bottom counts)/ (bottom counts + top counts) X100

% radiopharmaceutical tagged = 100 – (% free Tc-99m + % HR Tc-99m)

Procedure 4

USP Minimum Acceptable Purities:

Disofenin 90%
Mebrofenin 90%