Desorption of99Mo from spent99Mo/99mTc generator

A simple method for desorption and purification of⁹⁹Mo from spent⁹⁹Mo/^99mTc generators is described. The alumina column was washed successively with 0.9% saline water, 35% H₂O₂, and then the⁹⁹Mo was eluted with 2M NH₄OH. Ammonia and residual H₂O₂ were removed by heating the eluate. Finally,⁹⁹Mo solution was passed through a 0.2 m membrane filter to remove precipitated aluminium hydroxide.     

Rapid estmation of technetium in99Mo−99mTc generators

A nomogram is presented to estimate the radiooctivity of^99mTc in⁹⁹Mo−^99mTc generators, based on equations of radioactive equilibrium. Since the parent element decays through two isomeric states of the daughter, the ratio of the total mass of technetium per millicurie of^99mTc is a function of the time elapsed between two consecutive elutions. Values of the amount of^99mTc expressed as a mole fraction or in moles or grams of total technetium per millicurie of^99mTc^m are also presented.     

99mTc generator with hydrated MnO2 as adsorbent of 99Mo

An ^99mTc generator with MnO₂ as adsorbent of ⁹⁹Mo was investigated. Through batch experiments the retention of ⁹⁹Mo onto MnO₂was studied as a function of the shaking time and the pH value of the ⁹⁹Mo solution. It was found that ⁹⁹Mo showed a retention of 100% onto MnO₂ at the pH range from 3 to 11, and the equilibrium distribution was reached in less than 10 minutes. In column experiments the retention of ⁹⁹Mo onto MnO₂ was also high: 99.72%. In this case, the pH of the utilized ⁹⁹Mo solution was 5. The ^99mTc could be eluted from the MnO₂-⁹⁹Mo column by using either distilled water with a pH of 5 or an aqueous solution of 0.9% NaCl. With the saline solution, the ^99mTc elution yields were higher than 80%, and only one aliquot of 5 ml was needed to get these yields. The best results were obtained when the column was packed with 1 g of MnO₂. The water and the saline solution were passed through the column at a rate of 1.25 ml/min.     

A novel technique for the separation of99mTc from99Mo

A new technique for the separation of^99mTc from low specific activity⁹⁹Mo is reported. A separation based on the principle of precipitation of⁹⁹Mo as calcium molybdate has been investigated. On precipitating⁹⁹MoO ₄ ^2– from alkaline solution as calcium molybdate under controlled conditions, the^99mTcO ₄ ^– is found to remain quantitatively in the supernatant solution with little carry-over of⁹⁹Mo. This calcium molybdate (⁹⁹Mo) could be redissolved and reprecipitated at regular intervals, yielding^99mTc quantitatively in aqueous neutral solutions. Calcium molybdate precipitates containing up to 1.5 GBq of⁹⁹Mo and 130–180 mg of molybdenum were prepared and evaluated. The performance in terms of repeated^99mTc separation gave yields of 75–93% with acceptable readionuclidic and radiochemical purity.     

Altered [99mTc]Tc-MDP biodistribution from neutron activation sourced 99Mo

Journal of Radioanalytical and Nuclear Chemistry - Given potential worldwide shortages of fission sourced 99Mo/99mTc medical isotopes there is increasing interest in alternate production...     

Hydrated titanium dioxide as an adsorbent for99Mo−99mTc generator

The adsorption behaviour of⁹⁹Mo in the form of molybdate and of^99mTc 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. A^99mTc-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.     

Pharmaceutical grade sodium [99mTc] pertechnetate from low specific activity 99Mo using an automated 99Mo/99mTc-TCM-autosolex generator

Performance study of a computer controlled automated closed cyclic module for the separation and recovery of ^99mTc from low specific activity (n, γ) ⁹⁹Mo using methyl ethyl ketone (MEK) solvent extraction technique named ⁹⁹Mo/^99mTc-TCM-AUTOSOLEX (Technetium automated solvent extraction) Generator is described. The entire system is automated and controlled by a user-friendly PC based graphical user interface that actually supervises process via an embedded system based electronic controller. The average yield of separation of ^99mTc was above 85 % and ⁹⁹Mo breakthrough in ^99mTc pertechnetate was <0.002 %. The sodium pertechnetate obtained was a clear solution having pH 6–7, Radiochemical (RC). Purity >99 %, MEK content <0.1 % (v/v), Al and Mo content <10 µg/ml. R. C. Purity of ^99mTc-radiopharmaceuticals studied was not less than 96 %. Bio-Quality control studies confirm that sodium pertechnetate obtained was sterile and pyrogen free. Imaging studies in animals and humans with limited radiopharmaceuticals show that the quality of ^99mTc-pertechenate obtained in the present module was good enough to do clinical study.     

Separation and purification of 99mTc from 99Mo produced by electron linear accelerator

The medical radionuclide ⁹⁹Mo was produced by the ¹⁰⁰Mo(γ,n) reaction using bremsstrahlung photons generated by an electron linear accelerator. The amount of ⁹⁹Mo produced was compared to that predicted by calculation using the particles and heavy ion transport code system. From the ⁹⁹Mo produced, highly pure ^99mTc was separated using the so-called technetium master milker, and the chemical yield of ^99mTc was 83–99 %. The installation of a new complex using this method and the electron linear accelerator with the preferable specification was suggested, and a possibility to supply the demand of ^99mTc was discussed and shown.

     

Examination of a portable99Mo/99mTc isotope generator /SUBLITECHR/

Three SUBLITECH^R technetium generators were milked and generator products were tested for 5 d. Radionuclidic and radiochemical purity, pH of sodium pertechnetate solutions were -emitting impurities and pirogenity were not carried out. We can summarize that generators were running efficiently during our test period and in all cases the pertechnetate produced met the requirements of the European Pharmacopoeia.     

A99Mo-99mTc generator based on the use of zirconium molybdophosphate-99Mo gel

A modified⁹⁹Mo–^99mTc gel generator is described. The present generator uses an insoluble zirconium molybdophosphate (ZrMP) gel tagged with⁹⁹Mo. Molybdenum-99 is chemically combined in the gel structure and cannot be eluted from the matrix. The presence of phosphate increases the chemical stability of the gel and decreases the molybdenum breakthrough. The prepared gel is sufficiently porous to permit ready diffusion of^99mTcO ₄ ^– which can be cluted with saline in yields of up to 90%. The gel was found to contain 25.1% Mo, 21.9% Zr, and 0.7% P in a molar ratio of 1.09:1.0:0.09, respectively. The high molybdenum content of the gel allows the use of cheap, non-polluting (n, )⁹⁹Mo. The eluted^99mTc was of high purity and can be used for medical and pharmaceutical applications.     

Separation of99mTc from parent99Mo by solid-phase column extraction as a simple option for a new99mTc generator concept

Evidence is obtained to show that the liquidliquid extraction separation of^99mTc from⁹⁹Mo with methyl ethyl ketone, methyl propyl ketone and methyl isobutyl ketone can be transformed into a solid-phase column extraction procedure. The aqueous alkaline⁹⁹molybdate solution is immobilized on a column of a granular large-pore diatomaceous earch support, which is the neluted with the abovementioned extractants. Rapid and clean separation of^99mTc can be with all three solvents. The^99mTc can be back-extracted from the organic phase on a column filled with distilled water /or saline/ loaded granular diatomaceous earth /Extrelut^®/. The possibility of using the abovementioned procedure as a basis for a new^99mTc/⁹⁹Mo generator concept is envisaged.     

Production of 99Mo/99mTc by photonuclear reaction using a natMoO3 target

Journal of Radioanalytical and Nuclear Chemistry - Amount estimation of production of 99Mo required for medical applications was carried out by utilizing an electron linear accelerator with...     

Preparation of 99Mo/99mTc generator based on alumina 99Mo-molybdate (VI) gel

In this work alumina ⁹⁹Mo-molybdate (VI) gel is evaluated as a column matrix for use in the preparation of small chromatographic column type ^99mTc generator. Alumina molybdate (VI) gel is prepared by dissolving inactive MoO₃ with aluminum foil in 5 M NaOH solution containing ⁹⁹Mo radiotracer. After complete dissolution, 0.5 H₂O₂ was added to the reaction mixture solution and acidified to pH 5.5 with concentrated HNO₃. The formed AlMo precipitate was washed with NaNO₃ solution, dried at 50 °C for 24 h and then packed in the form of a chromatographic column for elution of the generated ^99mTc radionuclide with physiological saline solution (0.9 % NaCl). Greater than 86 % of the generated ^99mTc activity is immediately and reproducibly eluted with passing 10 mL of the saline solution through 2.0 g of alumina ⁹⁹Mo-molybdate column bed at a flow rate of about 1.0 mL/min. The high radiochemical ≥98.6 % TcO₄ ^?, radionuclidic ≥99.90 % ^99mTc and chemical purities of the eluates satisfy the specifications for use in nuclear medicine.     

Evaluation of proton induced reactions on 100Mo: New cross sections for production of 99 mTc and 99Mo

The use of the ⁹⁹Mo^99mTc generator in nuclear medicine is well established world wide. The production of the ⁹⁹Mo (T_1/2 = 66 h) parent as a fission product of ²³⁵U is largely based on the use of reactor technology. From the early 1990's accelerator based production methods to provide either direct produced ^99mTc or the parent ⁹⁹Mo, were studied and suggested as potential alternatives to the reactor based production of ⁹⁹Mo. A possible pathway for the charged particle production of ^99mTc and ⁹⁹Mo is irradiation of molybdenum metal with protons via the reaction ¹⁰⁰Mo(p,2n)^99mTc and ¹⁰⁰Mo(p,pn)⁹⁹Mo, respectively. The earlier published excitation functions show large differences in their maximum that result in large differences in the calculated yields. We therefore decided to study the excitation function for these proton-induced reactions. In this work the newly measured excitation functions as well as an evaluation of earlier measured data and a discussion of the observed disagreements are presented.     

Determination of molybdenum in biological materials by combined extraction of99Mo and99mTc

Combined extraction of⁹⁹Mo and its daughter-product^99mTc enables a rapid determination of molybdenum in biological samples by neutron activation analysis. A procedure and its application to standard kale powder and standard animal blood are reported.     

Preparation of99Mo,132Te isotopes and99mTc,132I generators

Adsorption and desorption of⁹⁵Zr−⁹⁵Nb,⁹⁹Mo,¹⁰³Ru,¹³²Te and²³⁹Np in a HCl-alumina system were studied in order to purify⁹⁹Mo and¹³²Te obtained by the cation-exchange separation of fission products and to prepare highly pure^99mTc and¹³²I generators.⁹⁹Mo and¹³²Te, of which radionuclidic purity was over 99.99% and 99.999%, respectively, could be obtained by passing the cation-exchange separated Mo and Te fractions through alumina columns, by washing with HCl and finally by eluting⁹⁹Mo with 1M NH₄OH and¹³²Te with 3M NaOH. In order to raise the recovery of⁹⁹Mo and¹³²Te from the alumina columns, they should be eluted as quickly as possible after the adsorption. The direct use of the alumina column containing⁹⁹Mo or¹³²Te as the generator allowed milking of^99mTc or¹³²I, of which radionuclidic purity was over 99.999%. Milking yields of^99mTc with 0.1M HCl and¹³²I with 0.01M NH₄OH were 77% and 90%, respectively. The latter value was much higher than that in usual performance of the generator.     

Determination of alpha and pure beta emitting impurities in99Mo/99mTc generator eluates

The determination of α- and pure β-emitting impurities in⁹⁹Mo/^99mTc generator eluates before application is discussed. It is shown that α-emitters in ≥10 mCi eluates can be determined in a proportional counter or an α-spectrometer within 30 min with detection limits lower than the European Pharmacopoeia limit (10⁻⁷% of the main activity).⁸⁹Sr and⁹⁰Sr are determined after chemical separation, consisting of ion exchange to separate the main activity (TcO ₄ ⁻ ), shaking with charcoal to separate colloidal particles containing Mo and precipitation of Sr as oxalate or sulfate. The precipitate is measured in a low-level counter. For eluates with an activity of ≥10 mCi the detection limits are one order of magnitude lower than the activity limit given by the European Pharmacopoeia for⁹⁰Sr (6×10⁻⁶% of the main activity). The time needed for chemical separation and activity measurement is about 30 min.