Sn-alanine kits were prepared in lyophilized form containing 7.02·10–2 M -alanine and 5.5·10–4M stannous chloride dihydrate. The optimal pH value of the preparation was found to be equal to 4.3–5.1. The radiochemical purity and the stability of99mTc-alanine were assessed by gel filtration column scanning techniques (GCS) and thin layer chromatography, and the labelling yield of the complex was higher than 95%. The organ distribution data in mice showed that more than 90% of the injected dose had been accumulated in the liver. However, a negligible amount of radioactivity was detected in the non-target organs. The stability of99mTc-alanine was followed for 5 hours and the Sn-alanine kit was stable for at least 3 months.
Fission neutron spectrum averaged cross-sections were measured for the reactions64Zn(n, p)64Cu,67Zn(n, p)67Cu and68Zn(n, )65Ni by the activation technique, using radiochemical separations and -spectroscopy. The preparation of64Cu and67Cu in a nuclear reactor was studied. The64, 67Cu was separated from zinc matrix activity using anion exchange column technique.
Potassium copper nickel hexacyanoferrate(II) [KCNF] was prepared by treating potassium nickel hexacyanoferrate(II) with copper nitrate solution in 0.1M HNO3. The resulting material was dried at various temperatures. Chemical analysis, i.r., thermal decomposition and surface property measurements were used to characterize the material. The adsorption of cesium from aqueous solutions on KCNF was investigated and optimized as a function of equilibration time and pH. The material dried at 110°C was found to be fairly stable in dilute acids, salt solutions, high doses of gamma-radiation and at high temperature. It also showed better surface properties and a high value of ion exchange capacity (2.25 mmol·g–1) for cesium.
Adsorption of cesium from aqueous solutions on potassium copper nickel hexacyanoferrate(II) (KCNF) has been investigated in batch experiments and optimized as a function of concentration of acids, salts and adsorbate using a radiotracer technique. The results are presented in terms of distribution coefficient, Kd (ml·g–1). The uptake of cesium obeys a Freundlich adsorption isotherm over the concentration range of 3.7 to 37 mmol·l–1 with b values of 0.77, 0.68 and 0.56 at temperatures of 293, 313, 333 K, respectively. The Langmuir adsorption isotherm is followed in the concentration range of 15 to 75 mmol·l–1 in the same temperature range. The values of limiting adsorption concentration (Cm) have been found to be 2.58, 2.44 and 2.32 mmol·g–1. The heat of adsorption was calculated as 26.43 kJ·mol–1. The influence of a number of anions and cations on cesium retention has also been studied. Column experiments have been performed and breakthrough have been obtained under different operating conditions. The low cesium capacity of 1.1 mmol·g–1 has been obtained under dynamic conditions as compared to batch experiments. Desorption of cesium from the column has been achieved (45.4%) by nitric acid solution of 8M concentration at a flow rate of 0.5 ml·min–1.
Biological and radiochemical quality control of indigenous (Pinscan) diagnostic cold kits of Methylene Diphosphonate (MDP), Tin-colloid and Diethylene Triamine Pentaacetic Acid (DTPA) was performed in parallel with imported Amersham's kits (Amerscan). The results of radiochemical purity, sterility, apyrogenicity and biodistribution of indigenous (Pinscan) kits were good and quantitatively and qualitatively comparable to those obtained with Amersham's (Amerscan) imported kits.
The available six types of Sephadex and one type of Sepharose have been applied in the separation of technetium fractions in99mTc-labelled radiopharmaceuticals produced in our laboratory using the GCS technique. By this technique the chemical state and the percentage of99mTc-fractions have been determined. The resolution efficiency of some gel types were found to be significantly influenced by the pH of the eluent. The results obtained from the experiments indicated that Sephadex G-25 Fine was the best and can be routinely used in the radiochemical analysis of the following kits:99mTc-HSA,99mTc-DTPA and99mTc-HIDA and G-100 for99mTc-PYP. With99mTc-HSA and99mTc-PYP kits, 0.9% NaCl eluents at pH 3.2 and pH 2 to 2.5, respectively, were found to be necessary for the separation of99mTc-fractions. G-50 Fine was found to be the best gel between the others in the separation of99mTc-fractions in testing of the weak radiopharmaceuticals,99mTc-GH and99mTc-MDP. The development of99mTc-MDP with the eluent at the same pH as the preparation gives negligible interaction effect.
Authors:A. Mushtaq, M. Mansoor, H. Karim, and M. Khan
The adsorption behaviour of99Mo in the form of molybdate and of99mTc in the form of pertechnetate on hydrated titanium dioxide was investigated at different molarities of hydrochloric acid. The adsorption capacity of molybdate on hydrated TiO2 is higher than on Al2O3. A99mTc-generator is suggested. This generator is based on the adsorption of (99Mo) molybdate on hydrated TiO2, at acidities of 0.05–0.1M. HCl.99mTc is eluted with 0.9% NaCl. Radionuclidic, radiochemical and chemical purities of the eluates were checked. This generator seems to have a great potential as compared to the traditional alumina generators.
Authors:M. Akhtar, A. Mushtaq, I. Haider, A. Aziz, and H. Karim
Effect of various amounts of reagents on the quality of99mTc–Sn-colloid has been studied, and a simple and reproducible method for its preparation particularly suitable for hospital pharmacy has been developed. PVP has been used as a stabilizing agent. A quick method of its bio-distribution has also been described.
Authors:M. Ashraf Chaudry, S. Nasir Ahmad, M. Iqbal, Bashir Ahmad, and H. Karim
Transport of99mTc across tri-n-butylphosphate (TBP) kerosene oil supported liquid membranes (SLM) has been studied under various conditions. Presence of dichromate ions helps avoid activity scavenging effects. Concentration increase of TBP, the complexing carrier used in the present study has a positive effect on flux (J) and permeability (P) of these ions, as up to 2.87M there is an increase in J and P values. HCl concentration in the feed solution increases J and P with their maximum values at 2.5–3.0M HCl in the feed. Above this concentration there is a decrease in flux and permeability of99mTc(VII) ions. The given ions are stripped with LiCl or NaCl solutions but more with NaOH. The optimum conditions of transport of the given ions are 2.5M HCl concentration in the feed, 2.87M TBP concentration in the membrane and 1M NaOH concentration in the strip solution. Equations have been developed to indicate the relation between flux, J, viscosity, of TBP in organic membrane phase, temperature, T, [H+], in the aqueous feed solutions and Tc ion concentration in the feed solution. Based on P, the values determined from liquid membrane experiments, the quantitative flux values of Tc(VII) ions were also determined as a function of TBP concentration in the membranes, and HCl and Tc concentration in the feed solution using the given equations. This experimental technique provides quantitative results from trace level activity transfer experiments.