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This work spotlights on the rapid and effective separation method for the no-carrier-added (NCA) 47Sc from natural irradiated Ti target using an anionic exchanger resin; AN-31 impregnated with 4-(2-Pyridylazo) resorcinol (PAR). The newly prepared resin (An-PAR) was characterized by FTIR and SEM. The Influence of pH on the distribution coefficients (Kd) of Sc(III) and Ti(IV) ions was investigated by batch technique and the results revealed that Ti(IV) ions are strongly adsorbed by AN-PAR rather than AN-31, while Sc(III) ions are weakly adsorbed on the both resin materials. The radiochemical separation of 47Sc(III) from irradiated natural Ti target was successfully carried out, where the elution efficiency for 47Sc reached 89 ± 1.5% with high radiochemical, radionuclidic and chemical purities. Our findings thus hold a great promise for the use of 47Sc radioisotope in the preparation of radiopharmaceuticals for theranostics applications.

Enzyme-linked immunosorbent assay (ELISA) is an economic and easy operation technique that has been widely used for the detection of protein in industry. However, the low loading capacity of the enzyme reporter has contributed to the low sensitivity of traditional ELISA, and the cross-linking procedures of the enzyme-labeled antibody in ELISA methods can lead to the inactivation of the enzyme, which will further decrease the sensitivity. To address this issue, herein we fabricated "carrier-free" nanoparticles to obtain a horseradish peroxidase (HRP) labelled reporter with a high HRP loading capacity. A disulphide-containing bis-N-hydroxy succinimide (NHS) crosslinker (NHS-SS-NHS) was used to control the link and release of traceless HRPs, thus without reduction of its enzymatic activity. The HRP nanoparticle (NanoHRP) was successfully applied for dot blotting and ELISA. When carcinoembryonic antigen (CEA) was used as a target, the detection limit of the NanoHRP-based ELISA was 0.005 ng mL-1, which was about 400 times more sensitive than traditional ELISA. A good correlation between the CEA concentrations and the response values measured by NanoHRP ELISA was obtained in the range of 0.005 to 1 ng mL-1. This concept could be exploited to improve ELISA tests, especially those requiring a high accuracy, to facilitate physicians in deciding the appropriate medical treatment.

We aim to investigate the separation of carrier free 99Mo as a homolog of Sg (element-106) from HCl, HNO3, H2SO4 and HF solutions using Bio-resin impregnated by trioctylamine (TOA), (BR-TOA). Distribution coefficient (Kd) of carrier free 99Mo has been investigated under various conditions by batch mode. To get knowledge towards the chemical behavior of Sg(IV) and Sg(VI), set of different chemical system, including mixed reducing agent with an acid solution for possible reduction and/or subsequent separation of 99Mo species was tested. The preliminary results are demonstrated that possible separation of different species of 99Mo as a homolog of Sg using BR-TOA.

67 Cu radioisotope is a beta particle-emitting nuclide used in radioimmunotherapy (RIT) as well as for imaging, tracer kinetic studies and dosimetry. 67 Cu can be produced by bombarding nat Zn with deuterons. In this study, the physical yields of 67 Cu via nat Zn(d,x) 67 Cu reaction channel as well as via subreactions of 68 Zn(d,2pn) 67 Cu, 67 Zn(d,2p) 67 Cu, 70 Zn(d,2p3n) 67 Cu, 68 Zn(d,x) 67 Ni(T 1/2 =21 s)→ 67 Cu and 70 Zn(d,x) 67 Ni(T 1/2 =21 s)→ 67 Cu in the nat Zn target have been calculated by using the MCNPX-2.6, TALYS-1.8 and SRIM codes. Also, the total cross sections for production of 67 Cu from nat Zn(d,x) 67 Cu reaction channel in the energy range of 15–45 MeV have been estimated by TALYS code. The best reaction to produce 67 Cu radionuclide in a carrier free form was chosen with deuteron energy around 30 MeV on 70 Zn thick target. Good agreement between the calculated results and the experimental values shows that the employed methods can be used for prediction and production estimation in cyclotron.

We performed solvent extraction of 99Mo and 181W from HCl and HCl/LiCl solutions into Aliquat 336-chloroform solutions. It is found that the extracted anionic species of Mo and W have a net charge of −1 from the logD versus log[Aliquat 336] plots. At high H3O+ concentrations, the D values in HCl were lower than those in HCl/LiCl, probably because of the protonation of anionic Mo and W species in HCl. The D values of Mo were significantly higher than those of W, suggesting that the extracted Mo and W species are different from each other and/or have different stabilities in HCl.

Carrier-free 32P was produced in KAlpakkam MINI reactor (KAMINI) via 32S (n, p) 32P using its small fast flux component. This method has established the flow-sheet for the production of 32P from sulphate targets such as magnesium sulphate and strontium sulphate which can withstand high temperatures of fast reactors unlike the conventionally used sulphur powder. The chemical processing involved (i) struvite precipitation method for magnesium sulphate and (ii) co-precipitation with ferric hydroxide method for strontium sulphate.

129 I has been successfully applied as tracer in environmental, geological, and oceanographic research. For samples with low stable iodine concentration and ultra low level 129 I, the sample preparation technique to separate iodine prior to AMS measurement has been a bottleneck, limiting the applicability of 129 I. We have reported a carrier-free method, using coprecipitation, to avoid the potential introduction of 129 I through the use of stable iodine carrier iodine. In this work, the detection limit and the analytical uncertainty of this method are investigated and minimum sample amount required to obtain reliable analytical results are estimated. The method is validated with a series of samples in ranges of known iodine concentrations and 129 I/ 127 I ratios. The results confirm our previous conclusion that an AMS target containing 5.0 μg iodine can be used for analyzing samples with 129 I/ 127 I > 10 −12 , and that for samples with 129 I/ 127 I −13 more than 25 μg iodine is necessary.

Five diglycolamide-appended calix[4]arene (C4DGA) ligands, viz. C4DGA with no substituent (L-I), n-propyl (L-II), 3-pentyl (L-III), n-octyl (L-IV) and both side (L-V) substituents were evaluated for the separation of carrier free 90Y from a 90Y–90Sr mixture using the flat sheet supported liquid membrane technique. Based on the results of earlier batch studies, the transport properties of the C4DGA ligands towards Y(III) and Sr(II) were monitored at two different feed acidities. The transport rates were significantly lower for 6 M HNO3 as compared to 3 M HNO3 as the feed. After 6 h, the observed trend of Y(III) transport with the C4DGA ligands using a feed of 3 M HNO3 was: L-I ~ L-III > L-V > L-IV > L-II which changed to L-III > L-I > L-IV > L-V > L-II for 6 M HNO3 as the feed. With 3 M HNO3 as feed, >97% Y(III) transport was obtained with L-I and L-III in 6 h. Comparative Sr(II) transport was negligible resulting in high decontamination factors. In a one-step separation process, using L-I as the carrier ligand, pure 90Y was obtained as the respective complex with either EDTA or DOTA. The highlights of this liquid membrane-based separation method comprise: its easiness, one-step separation, low ligand inventory, relatively pure product and continuous method.

Hydrogen titanate nanotubes (H2Ti3O7) were synthesized by hydrothermal process using 10 M NaOH and TiO2 anatase powder. The material synthesized was characterized by powdered X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to ensure the structural and morphological details of the above said nanotubes. This nanosized material behaved as a cation exchanger and it was employed to separate carrier-free 137mBa from 137Cs in column chromatographic technique using 1.0 M HNO3 as eluting agent.

The present article gives a comparative account of the efficiency of carrier-free 90Y separation from 90Sr by solvent extraction, flat sheet-supported liquid membrane (FSSLM) and hollow fiber-supported liquid membrane (HFSLM) methods using bis(2-ethylhexyl) phosphonic acid (PC88A) as the carrier extractant. The major focus of this work has been to develop the HFSLM method for the separation of Y(III) on a relatively large scale. The feed and receiver phase conditions were optimized by carrying out batch solvent-extraction studies. The extraction of Sr(II) by PC88A was negligible in the acidity range of 0.01–3 M HNO3, whereas the extraction of Y(III) was significantly large at lower acidity (≤0.1 M HNO3) with a separation factor (SF = DY/DSr) of 8.5 × 104. HFSLM studies suggested selective and efficient transport of Y(III) into 3 M HNO3 from a feed solution containing a mixture of Y(III) and Sr(II) at 0.1 M HNO3. On the other hand, transport of Sr(II) was negligible in the receiver phase. The purity of the...

N,N,N′,N′-tetra-2-ethylhexyldiglycolamide (T2EHDGA) has been used for the preferential extraction of 90Y from its mixture with 90Sr from HNO3 as well as HCl medium. The separation efficiencies have been found out under varying experimental conditions. The extracted species were determined from T2EHDGA concentration variation experiments carried out at 3 M nitric acid as well as HCl and were found out to be Y(X3)3·3(TEHDGA)(o) for both the extraction systems, where X = NO3− and Cl−, respectively. Comparison of the T2EHDGA and TODGA based separation methods is also made. In order to avoid third phase formation, iso-decanol has been used as the modifier in all the studies. The modifier content was optimized to 30% for 4 M HCl and 20% for 6 M HNO3 as the feed aqueous phases. Separation schemes were developed for the separation of carrier free 90Y and the purity was checked by the half-life measurement method.

The chemical investigation of E113 is likely to become soon feasible. The determination of chemical properties of carrier-free amounts of the lighter homologues of element 113, especially indium and thallium, allows designing experimental set-ups and selecting experimental conditions suitable for performing these studies. Here, we present investigations of the interaction of indium species with quartz and gold surfaces. Deposition temperatures as well as enthalpies of adsorption were determined for indiumTdep=739±20 °C (−ΔHads(In)=227±10 kJ mol−1) and for indium hydroxideTdep=250±20 °C (−ΔHads(InOH)= 124±10 kJ mol−1) respectively, on quartz. In case of adsorption of indium on a gold surface only a lower limit of the deposition temperature was establishedTdep>980 °C (−ΔHads(In)≥315±10 kJ mol−1). Investigations of macroscopic amounts of indium in thermosublimation experiments at similar experimental conditions were instrumental to establish a tentative speciation of the observed indium species.

Labeling of diethylenetriamine-N,N,N′,N″,N″-pentakis(methylenephosphonic) acid (DTPMP) with rhenium-188 using stannous chloride as a reducing agent has been investigated. Dependence of the yield of the 188Re–DTPMP complex on the concentration of the reducing agent, pH, reaction time, temperature, ascorbic acid and amount of carrier added has been studied. Under optimum conditions, the labeling yield of 188Re–DTPMP complex is 95% for the carrier-free 188Re but with the carrier-added 188Re the labeling yield is more than 97%. Furthermore, the stability of the 188Re–DTPMP complex against pH change and dilution with saline has been also studied. It is found that the addition of carrier stabilizes the 188Re–DTPMP complex against pH change and dilution.

At ETH Zurich a new method to measure directly the natural 10 Be/ 9 Be ratio of a sample with the compact (0.6 MV) AMS system Tandy has been developed, which allows us to use standard sample preparation methods and AMS techniques. Our results show that carrier-free measurements with compact AMS machines represent a fast, less expensive and more precise alternative for applications where only the relative variation of the 10 Be/ 9 Be ratio is needed. Increased source efficiency for (artificial) low carrier samples has been found. If this effect could be exploited for natural samples, it would open the field for other applications like in situ 10 Be-dating of quartz with compact, low energy AMS systems.

Twenty clinical scale alumina-based 188W/188Re generators and carrier-free 188Re has been produced at the Institute of Nuclear Energy Research (INER-Taiwan) for over ten years. 2845.6 GBq (76.9 Ci) of 188Re-perrhenate solution has been eluted from generators during the past ten years. We have used the harvesting 188Re solution for labeling radiopharmaceuticals, such as 188Re-HEDP, 188Re-MDP, 188Re-microsphere, 188Re-lipiodol, and 188Re-sulfur colloid, etc. The average eluting yield of 188Re is 78.6±5.8% that was investigated at 1115 harvesting times from 20 generators. Each generator can be used more than six months but the Millipore needs to be changed every two months for smooth harvesting and high yield of 188Re solution.

Solvent extraction studies of Y3+ and Sr2+ with 2‐ethylhexyl 2‐ethylhexyl phosphonic acid (KSM‐17) and octyl(phenyl)‐N,N‐diisobutylcarbamoylmethylphosphine oxide (CMPO) are carried out from aqueous media containing a wide range of nitric acid and other potential reagents to arrive at the operating conditions for the selective transport of 90Y using supported liquid membrane (SLM) containing these reagents as carriers. Since the transport data of 90Y using single cell SLM with KSM‐17 was available from our earlier experiments, single cell transport studies with CMPO carrier are only carried out to optimize the strippant phase. Transport studies with pure 90Y is carried out using a transport cell with two SLMs one with KSM‐17 and the other CMPO carriers to optimize the transport parameters. Based on these data the development of a two stage SLM system for the generation of carrier free 90Y from 90Sr source is described. The procedure described is amenable for automation and scale up.

Ultra-pure, carrier-free (209)Po solution standards have been prepared and standardized for their massic alpha-particle emission rate. The standards, which will be disseminated by the National Institute of Standards and Technology (NIST) as Standard Reference Material SRM 4326a, have a mean mass of (5.169 ± 0.003) g of a solution of polonium in nominal 2.0 mol▪L(-1) HCl (having a solution density of (1.032 ± 0.002) g▪ mL(-1) at 20 °C) that are contained in 5 mL, flame-sealed, borosilicate glass ampoules. They are certified to contain a (209)Po massic alpha-particle emission rate of (39.01 ± 0.18) s(-1)▪g(-1) as of a reference time of 1200 EST, 01 December 2013. This new standard series replaces SRM 4326 that was issued by NIST in 1994. The standardization was based on 4πα liquid scintillation (LS) spectrometry with two different LS counting systems and under wide variations in measurement and counting source conditions. The methodology for the standardization, with corrections for detection of the low-energy conversion electrons from the delayed 2 keV isomeric state in (205)Pb and for the radiations accompanying the small 0.45 % electron-capture branch to (209)Bi, involves a unique spectral analysis procedure that is specific for the case of (209)Po decay. The entire measurement protocol is similar, but revised and improved from that used for SRM 4326. Spectroscopic impurity analyses revealed that no photon-emitting or alpha-emitting radionuclidic impurities were detected. The most common impurity associated with (209)Po is (208)Po and the activity ratio of (208)Po/(209)Po was < 10(-7).

A procedure for the separation of 64,67Cu radioisotopes from irradiated natural zinc targets was developed. Production of 64,67Cu was carried out using 64,67Zn(n,p)64,67Cu reactions by fast neutron bombardment of natural zinc targets at The Second Egyptian Research Reactor (ETRR-2). The sorption behavior of 65Zn and 64,67Cu ions in HCl acid solutions showed high affinity of Cu ions towards 6-tungstocerate(IV) gel matrix compared with Zn ions. Carrier-free 64,67Cu radionuclides were separated from 65Zn on 6-tungstocerate(IV) column matrix by eluting the column with 10 ml 0.001 and 1M HCl acid solutions. The separated 64,67Cu radionuclides were of high chemical, radiochemical and radionuclidic purity.

Two widespread misconceptions regarding Tc are dealt with. First, it is shown that although primordial Tc has decayed completely, Tc is still present in nature due to natural processes, in addition to substantial man-made quantities. Thus, Tc cannot be considered as a purely artificial element. Second, it is shown that 99mTc from 99Mo/99mTc generators is certainly not carrier-free (CF) and that, “no-carrier-added” (NCA) is a more appropriate designation. As a quantitative measure of the amount of long-lived 99gTc carrier present in 99mTc preparations from generators, the Isotope Dilution Factor (IDF) is used and calculated for some practical situations.

Procedures are described for the extraction of carrier free iodine from 100 ml seawater samples, and the measurement of the 129 I/ 127 I ratio of this iodine by accelerator mass spectrometry (AMS) at the Gif-sur-Yvette AMS facility. The extraction procedure is simple, rapid and relatively inexpensive, with significantly reduced cross-contamination in the ion source and less current dependence of the AMS measurements compared to samples prepared using carrier. These features make very attractive the use of nuclear reprocessing derived 129 I as a tracer in the climatically sensitive regions of the North Atlantic and Arctic oceans.

A method for direct measurement of the natural 10Be/9Be ratio in a sample by AMS is presented. Samples of 100 ng of Be with 10Be concentrations orders of magnitude higher than in conventional 10Be AMS samples were produced without the addition of 9Be carrier and analysed using the accelerator secondary ion mass spectrometry (Accelerator SIMS) source of the PSI/ETH AMS facility. Special mounting techniques and the analysis procedure using a focussed Cs+ beam of up to 600 nA and beam spot diameter of 100 μm are described. The results of measurements on two test samples from Pacific ferromanganese crust D11–1 are presented and compared with similar measurements by conventional secondary ion mass spectrometry (SIMS). Background measurements at a level of ∼5 × 10−11 indicate that ratios of a few times 10−10 could be measured to a precision of ∼10%. PACS 29.17.+w; 29.30.−h; 82.80.Ms; 89.60.+x

Heavy-ion activation with ~55 MeV 11B beam on silver target leads to the production of carrier-free 111In, 116,117Te and 116,116m,117Sb radioisotopes in the target matrix. Liquid-liquid extraction, using Aliquat-336 and trioctylamine (TOA) as liquid anion exchangers in HNO3 and HCl medium, respectively, and di-(2-ethylhexyl)phosphoric acid (HDEHP) as liquid cation exchanger in ammoniacal medium was used to investigate the separation of the produced radioisotopes from the bulk target matrix.

The concept of tracer packet, which can be defined as “a group of carrier-free radioactive isotopes of few elements, which have been produced together with an objective to study some particular physical, chemical or biological systems” has been introduced in this paper. The tracer packet can be produced with low projectile energy (5-7 MeV/u) contrary to the multitracer technique. A thick cobalt foil has been irradiated consecutively with 16O, 7Li and 12C beams to produce the tracer packet containing carrier free radiotracers of Mn, Cu, Zn, Ga, Ge, As and Se which after removal of bulk cobalt can be used for further studies of essential micro nutrient elements.

A device for on-line electromigration studies of radio-elements in free electrolytes has been tested by measuring the absolute individual ion mobilities of no-carrier-added single charged anions [99mTc]TcO4 - and [18F]F- and differently charged cations [137Cs]Cs+, [57Co]Co2+ and [241Am]Am3+ in inert aqueous electrolytes at 298.1 K. The observed ion mobilities were found to be influenced by electroosmosis in the migration tube. A relation to correct this effect is proposed. In addition, it was shown that the effect of electroosmosis may be suppressed by chemical treatment of the surface of the migration tube.

A comprehensive review has been made to discuss the role of various radionuclides of lanthanide series elements in the field of nuclear medicine. The role of several pharmaceuticals labeled with radiolanthanides and used for investigative purposes like measurement of cerebral blood flow, bone density measurement, bone marrow imaging, etc., have been described. The role of lanthanide radionuclides in radiation synovectomy, radioimmunotherapy, etc., have also been discussed. Methods of preparation of some representative radiopharmaceuticals like153Sm-EDTMP,153Sm-HYP, have been presented. An outline on the production of carrier free radioisotopes of lanthanide series elements has been given.

Natural La2O3 irradiated with ∼80 MeV 12 C 6+ results in the formation of carrier-free isotopes, 146,147 Eu , in the matrix. The produced carrier-free radioisotopes have been quantitatively separated with 1% HDEHP from 10−3 M HCl solution. The europium radioisotopes have been successfully back extracted into DTPA and EDTA medium for biomedical applications.

The various methods of separation of carrier free lanthanide elements have been briefly described.

Carrier free promethium was produced by proton activation in neodymium target. Extraction behavior of both the elements were studied by HDEHP. A pronounced synergism had been observed by the binary mixture of HDEHP and PC88A. Presence of H2O2 in aqueous phase also increases the separation factor.

The various methods for separation of carrier free radionuclides of second transition series elements from the bulk target matrix has been discussed in brief.

Interval free flow zone electrophoresis is a new mode of free flow zone electrophoresis (FFZE), which facilitates purification of proteins and other molecular substances at very high resolution. It can be performed in the commercially available free flow electrophoresis (FFE) apparatus Octopus. The specimens are loaded and unloaded as usual with the help of a thin buffer film flowing between the two glass plates of the FFE. However, as long as electrical current is applied to a specimen, the medium flow is turned off and conditions of static column electrophoresis are simulated within the FFE device. Thereby electrohydrodynamic flow effects, which widen the sample bands migrating within the electric field, are eliminated while optimal heat removal from the thin buffer film is still possible and a sophisticated technique of harvesting of fractions remains available. Thus interval FFZE offers a gentle preparative method for purification of many kinds of charged molecular species such as proteins or...

Radioisotopes of 37 elements were isolated from a gold target irradiated with an energetic12C beam and were used as a multitracer to establish procedures for separating themselves into groups of carrier-, salt-and organic matter-free tracers. Solvent extraction with HDEHP and ethyl methyl ketone along with cation exchange yielded group tracers ready for application to chemical and biological studies.

The carrier-free radiotracers,52,56Mn,55,56,58Co and56,57Ni were produced simultaneously by accelerated α-particle activation of iron. They were subsequently studied through LLX using the liquid cation exchanger, HDEHP, as an extractant. A considerable enrichment of individual carrier free radionuclides of manganese, cobalt and nickel was achieved. Production and verification of purity of the carrier-free radiotracers at different stages of their extraction were carried out by γ-ray spectroscopic studies.

N,N,N',N'-tetraoctyl diglycolamide (TODGA) has been used as the stationary phase in an extraction chromatography resin (XCR) material prepared for evaluating the uptake and the separation behaviour of (90)Y and (90)Sr from acidic feeds. Chromosorb-W was used as the solid support material while the feed solution was usually 4M HNO(3). The batch uptake studies have suggested almost no Sr(II) uptake while Y(III) uptake increased with acidity up to 4M HNO(3) beyond which a decrease in the K(d,w) values were observed. Column studies were carried out and breakthrough profiles were obtained for both Y(III) and Sr(II). No breakthrough of Y(III) was noticed even when50 column volumes of the feed (carrier free (90)Y at 4 M HNO(3)) was passed through the column while about 20 column volumes were required for the breakthrough of Y(III) when the feed contained 1 g/L Y in 4 M HNO(3) spiked with (90)Y tracer. The reusability of the column was also studied which indicated in the deterioration of the column performance as shown by the sharp fall in the breakthrough volumes and was attributed to the probable leaching of the reagent from the support material. The role of absorbed dose was also investigated for Y(III) uptake. Separation of carrier free (90)Y tracer was carried out by loading the column with (90)Sr and eluting with 0.01M solutions of HNO(3) as well as EDTA. The purity of the product was ascertained by half-life method.

Monoclonal antibodies CHX-A-DTPA-HuM195 specific to CD 33 antigens on leukemia cells were labeled with carrier free 149Tb and 149Gd. Labeling yield and radiochemical purity were determined and in vitro studies concerning immunoreactivity, internalization and killing of leukemia HL-60 cells were performed.

Carrier-free radionuclides of tungsten and tantalum, 176,177W and 176,177Ta have been produced by heavy ion activation of holmium target with 97 MeV 16O5+ beam. Radiochemical separation scheme has been developed to isolate tungsten and tantalum radionuclides from the holmium target matrix.

A radiochemical procedure for separation of carrier-free22Na from bulk of Mg is described. The method involves the initial removal of bulk of Mg as Mg(OH)2 by means of ammonia followed by separation of the last traces of Mg by means of extraction with a cationic liquid exchanger, di-(2-ethylhexyl) phosphoric acid (HDEHP) in cyclohexane.

A method for the separation of carrier-free arsenic from bulk amount of germanium has been developed.74,73As has been produced through the reactionnatGe(p,xn)47,73As with 13 MeV protons obtained from Variable Energy Cyclotron, Calcutta. The separation is performed by the distillation of Ge followed by anion exchange separation of As(V) using Dowex 1×8 anion exchange resin. The overall chemical yield is found to be (87±3%).

The purpose of the study was to examine the suitability of using laser diffraction to measure the fine particle fraction (FPF) of drugs emitted from carrier-free dry powder aerosol formulations.Particle size distribution of terbutaline sulphate from Bricanyl Turbohaler, which contained loose agglomerates of drug particles only, was measured separately by laser diffraction apparatus equipped with a metal throat and a twin-stage, multi-stage liquid impingers, or Andersen cascade impactor at flow rates ranging from 28.3 to 100 l min(-1). In-line measurements were then conducted which allowed the same aerosolised particles to be measured first by laser diffraction then captured by an impactor or impinger for subsequent chemical analysis.A significant linear correlation (p0.001, R2 = 0.96, ANOVA) existed between the results obtained from two techniques when measurements were conducted independently. There was little difference in FPFs measured by inertial impaction and laser diffraction at the same flow rate. When in-line measurements were conducted, the FPFs measured by inertial impaction were approximately 0.7-0.9 times the aerosol FPFs measured by laser diffraction. This linear relationship was statistically significant and had a statistically insignificant y-intercept, regardless of inhaler batches, impinger types and measuring position of the laser beam.Laser diffraction could prove to be a reliable technique for development, evaluation and quality control of carrier-free, dry powder aerosol formulations.

Simultaneous production of carrier free89Zr and90,91m,92mNb through the (α, pxn) and (α,xn) nuclear reactions has been performed by α-particle activation of Y2O3 target. The sequential separation of the produced radioisotopes from the bulk target matrix has been achieved through LLX using TOA as a liquid anion exchanger. Formation of the carrier free radionuclides in the target matrix and their purity in different stages of separation have been verified by γ-ray spectrometry.

A procedure was developed for preparing 99.9% pure 103Pd by neutron irradiation of a thin rhodium wire in a cyclotron. 103Pd was isolated by extraction.

Procedure for preparing carrier-free 113Sn based on irradiation of targets enriched with 111Cd in a beam of α-particles was proposed and realized. Using a “stack of foils” procedure, the energy dependences of the yields of 113Sn and impurity nuclides were studied and the optimal energy of the α-particles was determined; 113Sn was isolated from the targets by diffusion.

Palladium activity produced in the (α, xn) reaction on ruthenium has been separated from a Ru metal target. Two methods have been followed for this carrier-free separation of Pd from Ru. The recovery of Pd has been found to be 60 and 90% in the two methods, respectively. Separated Pd was found to be free from any radiochemical and chemical impurities.

The different parameters of 11C formaldehyde synthesis from 11CO2 have been systematically studied in order to improve yields, reproductibility and specific radioactivity. With modifications brought to gas and reagents purity, 11CO2 trapping system, target and dehydrogenation catalyst treatment, 100 to 200 mCi of 11C formaldehyde are obtained at EOB + 10 mn, with a specific activity on the order of 600 mCi/μmole (maximum 1 Ci/μmole).

Nuclear decay of C3H4 in the presence of gaseous furan represents a simple and convenient synthetic route to carrier-free multitritiated 3-methyl- and 2-methyl-furan. Their application for biological studies appears particularly promising, on account of the favourable characteristics of the followed synthetic approach.

1′,2′-Dehydroolivetol and its monomethyl ether, 5′-bromoolivetol, and olivetol-5,-2H3, have been synthesized. Acid catalyzed condensation of the latter three compounds with p-mentha-2,8-dien-1-ol gave 1′,2′-dehydro-Δ8-THC methyl ether, 5′-bromo-Δ8-THC, and Δ9-THC-5′-2H3, respectively. 5′-Bromo-Δ8-THC served as a precursor of 4′,5′-dehydro-Δ8- and Δ8-THC, 4′- and 5′-hydroxy-Δ8-THC, 5′-dimethylamino-Δ8-THC and 5′-carboxy-Δ8-THC. Reduction of 4′,5′-dehydro-Δ8- and Δ9-THC in the presence of homogeneous catalysts afforded tritium labeled Δ8-THC (50 Ci/mmole) and Δ9-THC (58 Ci/mmole), respectively. Syntheses of Δ9-THC-11-2H3, Δ9-THC-11-14C cannabinol-5,-2H3′ and other labeled cannabinoids are described.

Mercury(II) oxide oxidation of naltrexone (1a) and naloxone (1b) gave 15,16-didehydronaltrexone (4a) and 15,16 didehydronaloxone (4b). Subsequent reduction of 4a with tritium gas afforded naltrexone-15,16-3H2 having a-specific activity of 15.3 Ci/mmole. Subsequent equilibration of 4b with carrier free tritium oxide followed by sodium cyanoborohydride reduction yielded naloxone-15-3H having a specific activity of 4 Ci/mmole.

The alpha emitting radiohalogen 211At has potential use as a radiotherapeutic agent when linked to biologically active molecules. The range of compounds which may be astatinated is limited by relative lack of knowledge of organoastatine syntheses. The production of astatovinyl steroids was carried out via electrophilic substitution of tri-n-butylstannylvinyl steroids with astatide in the presence of mild oxidizing agents. The astatinated steroids are synthesized rapidly and in carrier-free fashion yielding compounds of high radiochemical purity.