OctreoScan QC

In-111 Pentetreotide (Octreoscan) Quality Control Procedure

Materials needed:

*Sep-Pak cartridge
Methanol
Distilled Water
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.

Procedure:

1. SeeĀ General QC Procedure.

2. Prepare Sep-Pak:

a. Push 10 ml of methanol through the cartridge. Discard eluate.
b. Push 10 ml of distilled water through the cartridge. Discard the eluate.
c. Make sure that the cartridge is kept wet and that there is no air bubble present.

3. Analyze Sample:

a. Place 0.05 ml – 0.1 ml of sample in the long end of the cartridge.
b. Slowly push 5 ml of distilled water through the cartridge. Collect in counting vial.
c. Slowly (dropwise) push 5 ml of methanol through the cartridge. Push two 5 ml of air through the cartridge. Collect eluate in counting vial.
d. Place Sep-Pak in the third counting vial.

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

Counts:

Water: contains free In-111

Methanol: contains the In-111 labeled pentetreotide

Cartridge: contains non-elutable impurities

% free In-111 = (counts of water)/(sum of all three fractions counts) x 100

% tagged In-111 = (counts methanol)/(sum of all three fraction counts) x 100

USP Minimum Acceptable Purities:

Octreoscan 90%