Mertiatide (MAG-3) Quality Control Procedure

Materials needed:

*Sep-Pak cartridge
200 proof Ethanol
1:1 Ethanol:0.9% Saline solution
0.001 N HCl
3 Counting vials with screw top lids
MCA or SCA or Scaler with scintillation well

*Alternative QC procedures exist, but this procedure has proven to be more reliable. Use of other solvents and medium must be validated before routine use.


1. SeeĀ General QC Procedure.

2. Prepare Sep-Pak:

a. Push 10 ml of 200 proof ethanol through the cartridge. Discard eluate.
b. Push 10 ml of 0.001 N HCl through the cartridge. Discard the eluate.
c. Dry cartridge by pushing 5 ml of air through the cartridge.

3. Analyze Sample:

a. Place 0.1 ml of sample in the long end of the cartridge.
b. Slowly push 10 ml of 0.001 N HCl through the cartridge. Collect in counting vial.
c. Slowly (dropwise) push 10 ml of 1:1 ethanol:0.9% saline through the cartridge. Collect in counting vial.
d. Place Sep-Pak in the third counting vial.

4. Assay each vial in the dose calibrator or well counter.


0.001 N HCl: contains free Tc-99m sodium pertechnetate and some hydrolyzed reduced.

1:1 solution: contains the tagged mertiatide

Cartridge: contains hydrolyzed reduced Tc-99m plus other non-elutable impurities

% free Tc-99m = (counts of HCl)/(sum of all three fractions counts) x 100

% tagged mertiatide = (counts 1:1 solution)/(sum of all three fraction counts) x 100


USP Minimum Acceptable Purities:

MAG-3 90%