No abstract

No abstract

Prostate Specific Antigen (PSA) is a glycoprotein with a molecular weight of approximately 34,000 daltons serine protease secreted exclusively by prostatic epithelial cells that lining acini and prostate gland. Increased of PSA levels can be caused by prostate cancer or benign prostate enlargement (benign prostatic hyperplasia, BPH). PSA in the blood was found in the free condition (free PSA) and most of the bound protein (complexed-PSA, c-PSA). Measuring levels of PSA was found in the blood can be done by several methods such as by immunoradiometricassay (IRMA) methods or ELISA methods. IRMA method is one of immunoassay techniques using radionuclides ,/' 125 oJ I as a tracer, so the sample in small 13 quantity can be detected The purpose of this study was obtained PSA reagent kit that includes 1251labeled PSA as a tracer, PSA coated tube and PSA standard that requirements of the kit, then it can be optimized assay design, that eventually PSA reagent kit can be used for early detection of prostate cancer. It has been done labeling of Mab PSA using 125 1with reaction time was 90 seconds, amount of PSA MAb was 75 ugram and the activity of Na_ 125I was 1000 flCi. Preaparation of PSA coated tube using 0.05 M Na2C03 solution, at pH: 9.6 with volume was 250 ml., standard PSA with 0.025 Mphosphate buffer at pH 7.4 containing 5% BSA and 0.1% NaN3, and resulting at 1,25% and 14,12% respectively of NSB and BIT that requirement of the kit.Keywords: Prostate cancer, PSA, IRMA,NSB, Maximum Binding

<p>Immunoradiometric assay (IRMA) is a method of analysis based on immunological reactions of antigens-antibodies binding. This highly specific and sensitive method was used for in vitro diagnosis in small quantity of sample. Center for Radioisotope and Radiopharmaceutical Technology, BATAN has developed Thyroglobulin IRMA Kit using coated tube method that can determine thyroglobulin levels in microgram quantities. Coated tube was made with immobilisation of anti thyroglobulin into polistyrene tube. Development of IRMA kit performed through several steps including: optimization component of kit, optimization assay and kit validation. Optimization of coated tube involved selection and volume of solvent, using blocking and non-blocking agent, and volume of blocking agent. The optimum condition for coated tubes was found to be using 0.1M phosphate buffer pH 7.4 with coating volume of 500 μL, 3% BSA in 500 μL blocking agent 0.1M phosphate buffer pH 7.4, with maximum binding and non-specific binding (NSB) of 60.58 and 1.40%, respectively. The optimized coated tube was found to be stable up to 4 weeks.</p>

Technetium-99m (Tc-99m) labeled tetrofosmin kit has been widely used in hospitals including in Indonesia. Usually, tetrofosmin kits and Tc-99m pertechnetate are supplied separately, but recently there has been a new trend where Tc-99m tetrofosmin is supplied in the form of the ready-to-inject product. To prepare such a product it has to be proven that tetrofosmin can be labeled with high activity of Tc-99m and the resulted Tc-99m tetrofosmin, remains stable within shipping time until being used in hospitals. In this investigation, locally produced tetrofosmin kits were labeled with various radioactivity of Tc-99m ranging from 150 mCi to 400 mCi, their radiolabeling yields or radiochemical purity was analyzed using SepPak C18 column, and the radiochemical stability was assessed within 30 hours. The worst storage condition was also studied by analyzing its radiochemical purity after being stored at extreme temperatures for several hours. The results showed that tetrofosmin kit can be highly labeled with up to 415 mCi of Tc-99m, and stable up to 30 hours in room temperature, and there is a tendency that higher radioactivity leads to more decreasing in radiochemical purity. Stability study in extreme temperatures showed that the product can withstand its stability within 6 hours in 40C, but it decreased rapidly to less than 70% within 1 hour when stored in 50C. It concludes that the quality of Tc-99m tetrofosmin as an injectable radiopharmaceutical can be maintained during transportation by storing it at cool temperature.