Radiopharmaceuticals

	4: 99mTc- (V) - DMSA  (Addenbrooke's Hospital, Cambridge)
	Preliminary Instructions
1.	Calculate the volume of the stock solution of sodium pertechnetate 99mTc which will contain 1000 MBq (depending on the number of patients to be scanned) at the time of injection. Let this equal x ml.
2.	Affix an injection number to an Amersham DMSA kit vial labelled "A".
3.	Affix an injection number to a nitrogen filled vial labelled "B", (mixing vial).
4.	Affix an injection number to a nitrogen filled vial labelled "C", (final injection).
	Preparation Method
1.	Prepare a solution of sodium bicarbonate 7%w/v: Sodium bicarbonate inj. (8.4%) 8.3 mls to 10 mls of Water for inj. B.P.
2.	Open Amersham DMSA vial under laminar flow and add:- 4.44 mg DMSA 120.00mg Dextrose 5.04 mg sodium bicarbonate
3.	Add 0.4 mls of the sodium bicarbonate solution and shake carefully to dissolve.
4.	Withdraw the required volume of sodium pertechnetate solution (x ml) from the stock vial and transfer to mixing vial "B".
5.	Add 2.5 - x ml sodium chloride 0.9% injection.
6.	Add 0.1 ml of the DMSA solution to vial "B".
7.	Millipore the resulting solution into vial "C" using a 0.22µm filter and an air bleed needle. Check volume of injection.
8.	Measure the activity of 99mTc contained in the vial and label
	NOTE: For two patients, 0.2 mls of DMSA solution should be transferred to 5 mls of pertechnetate solution and pro rata.
	Storage: In refrigerator.
	Shelf life: 6 hours after preparation.
	Radiochemical Purity
	TLC: (MERCK TLC Plates silica gel 60 F254, 5 x 10 cm. BDH Code 155562L).
	SOLVENT SYSTEM: Butan-I-ol :Glacial Acetic Acid :Distilled Water 3:2:3
	NB. Solvent system must be freshly prepared. Do NOT allow the spot to dry. Run for approx. 2hrs
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