The synthesis of 6-nitroquipazine, a very potent and selective 5-hydroxytryptamine (5-HT; serotonin) uptake inhibitor, labeled with tritium is described. High specific activity [3H] 6-nitroquipazine could be prepared by the nitration of [3H] quipazine using a mixture of equal volumes of sulfuric acid and nitric acid. The radiochemical yield was approximately 50% based on [3H] quipazine. The radiochemical purity was more than 95% from high performance liquid chromatography (HPLC) and thin layer chromatography (TLC) determinations. [3H] 6-Nitroquipazine would be a new suitable radioligand for studying 5-HT transporter complex in brain and platelets.
This note describes a method of direct measurement of airborne gamma-rays primarily from222Rn daughters using a NaI (Tl) scintillation spectrometer with lead shields. This method has the advantage of being able to maintain the system easily compared to other usual systems including a pump. The pulse-height distributions are successively fed to a floppy disk in a personal computer every unit time. The gain shifts can be corrected automatically by a computer program. This technique would be applicable to the estimation of222Rn daughters concentration and to examination of disequilibrium between214Pb (RaB) and214Bi (RaC) and of those height distribution up to about 200 m. The accuracy for estimating the concentration is as good as that of the filter method.
A new procedure was developed for the waste treatment of radioactive phenol on a laboratory scale. Waste phenol was dissolved in water (2 % as phenol), and ferrous ion (10 mg/l as Fe2+) was added. Hydorgen peroxide (6 % as H2O2) was added seperately in three steps, 20, 30, and 50% of the volume, in order to avoid rapid reaction. The solution was heated at 80-90 °C for several hours in a beaker covered with a watch glass till the color of the solution changes from red purple to pale yellow. Then, the solution was neutralized with sodium hydroxide and heated for 1 h to decompose excess hydrogene peroxide. When the procedure is carried out with four 2 l beakers on a hot plate, 100 ml of phenol (1200 ml of the aqueous solution saturated with phenol) can be oxidized simultaneously.