1. BIOASSAY OF STRONTIUM CHLORIDE INJECTION Strontium chloride Sr 89 is a radiopharmaceutical. Radiopharmaceuticals are radioactive agents that may be used to diagnose some diseases by studying the function of the body's organs or to treat certain diseases. Strontium chloride Sr 89 is used to help relieve the bone pain that may occur with certain kinds of cancer. The radioactive strontium is taken up in the bone cancer area and gives off radiation that helps provide relief of pain. US Brand Name - Metastron

2. Strontium chloride injection is a sterile solution of radioactive strontium in the form of strontium chloride in water for injection. Strontium chloride injection contains not less than 90% & not more than 110% of labelled amount of sr as strontium chloride expressed in megabecquerels per ML. SPECIFIC ACTIVITY – Not less than 2.96MBq per mg of strontium at the time indicated in labelling. PACKAGING AND STORAGE – Preserve in single dose containers that are adequately sheilded. LABELLING – Time and date of calliberation, amount OF SR EXPRESSED AS MG PER ml, concentration as megabecquerals per ml. CAUTION- Radioactive material.

3. USP STANDARDS – RADIONUCLEIDE IDENTIFICATION BACTERIAL ENDOTOXIN – Limit of endotoxin content being not more than 175/V USP endotoxin unit per ML of injection in which V is maximum recommended total dose, in ML at the expiration date. RADIONUCLIDIC PURITY – Determine radioactivity of each gamma emmiting radioactive impurity. In kBq per MBq of sr in injetion. The total activity of gamma emmiting impurities is not greater than 370kBq per 37MBq.

4. CHEMICAL PURITY – (limit for alluminum) Nitric acid diluent – dilute 40 ml of nitric acid with water to 1000ML. Standard preparations- transfer 2000mg of aluminium metal to 1000ml volumetric flask, add 50 ml of 6N HCL, and allow reaction to proceed until aluminium is dissolved. Dilute with water to volume and mix. Transfer 5ml of this solution to volumetric flask dilute to volume mix. Transfer 10ml of this solution to 100ml volumetric flask, dilute with nitric acid. Trasfer 1,2,4ml portions of this solution to separate 100ml volumetric flasks, dilute to nitric acid to volume and mix. these solutions contain 0.01,0.02 and 0.04 microgram of Al per ml. Test preparation – transfer 1ml of injection to a 100ml volumetric flask and carefully add 4ml of nitric acid. dilute with water to volume and mix. Procedure – determine absorbances of standard preparations and test preparation at aluminium emmision line at 309.3nm with an automatic absorbtion spectrophotometer. Equipped with aluminum hallow cathode lamp and flameless electrically heated furnace, using Nitric acid diluent as the blank. Plot absorbances of the standard preparations versus contents of aluminium drawing straight line. From graph determine the quantity of aluminium in each ml.

5. ASSAY – 1.Potassium chloride solution - Dissolve 1.9g of potassium chloride in water, dilute with water to 1000ml,and mix. This solution contains 1000µg of potassium per Ml. 2.Strontium stock solution – Transfer 1.685g of strontium carbonate. Accurately weighed to a100ml volumetric flask, add water to dissolve. add 10ml of hydrochloride, dilute with water to volume and mix to obtain a solution containing 10,000µg of strontium per ml. 3.Standard preparations – pipet 10ml of strontium stock solution in to 100ml volumetric flask. Add 10ml hydrochloric acid, dilute with potassium chloride solution to volume and mix. transfer 10ml,20ml,respectively,of this solution in to separate 1000ml flasks. dilute with potassium chloride solution to volume and mix. these standard preparations contain 100 and 200µg of strontium per ml.

6. Assay preparation – pipitte 0.1 ml of injection in to small beaker. Add 5ml of KCL solution and mix. PROCEDURE – Concomitantly determine absorbances of standard and assay preparation at strontium emission line of 407.8nm with an atomic absorption spectrophotometer equipped with a strontium hallow cathode lamp and a nitrousoide-acetyulene flame, using potassium chloride solution as blank. Plot the absorbances of standard prepartion versus concentration in µg per ml,of strontium in the assay preparation. Calculate the quantity in µg, of strontium in each ml of the injection taken by the formula 51C in which c is concentration in µg per ml, of strontium in the assay preparation.