Resin Cartridge Research Articles

Separation and measurement of thorium, plutonium, americium, uranium and strontium in environmental matrices

A technique for the isolation of thorium (Th), plutonium (Pu), americium (Am), uranium (U) and strontium (Sr) isotopes from various environmental matrices has been adapted from a previously published method specific to water samples ( Maxwell, 2006). Separation and isolation of the various elemental fractions from a single sub-sample is possible, thereby eliminating the need for multiple analyses. The technique involves sample dissolution, concentration via calcium phosphate co-precipitation, rapid column extraction using TEVA™, TRU™ and Sr-Spec™ resin cartridges, alpha spectrometry for Th, Pu, U and Am and Cerenkov counting for Sr. Various standard reference materials were analysed and chemical yields are in the range of 70–80% for Th, Am, U and Sr and 50–60% for Pu. Sample sizes of up to 10 L for water, 5 g for dry soil and sediment and 10 g for dry vegetation and seaweed can be processed using this technique.

Rapid separation of actinides and radiostrontium in vegetation samples

A new rapid method for the determination of actinides and radiostrontium in vegetation samples has been developed at the Savannah River Site Environmental Lab (Aiken, SC, USA) that can be used in emergency response situations or for routine analysis. The actinides in vegetation method utilizes a rapid sodium hydroxide fusion method, a lanthanum fluoride matrix removal step, and a streamlined column separation process with stacked TEVA, TRU and DGA Resin cartridges. Lanthanum was separated rapidly and effectively from Am and Cm on DGA Resin. Alpha emitters are prepared using rare earth microprecipitation for counting by alpha spectrometry. The purified 90Sr fractions are mounted directly on planchets and counted by gas flow proportional counting. The method showed high chemical recoveries and effective removal of interferences. The actinide and 90Sr in vegetation sample analysis can be performed in less than 8 h with excellent quality for emergency samples. The rapid fusion technique is a rugged sample digestion method that ensures that any refractory actinide particles or vegetation residue after furnace heating is effectively digested.

Rapid separation method for actinides in emergency air filter samples

A new rapid method for the determination of actinides and strontium in air filter samples has been developed at the Savannah River Site Environmental Lab (Aiken, SC, USA) that can be used in emergency response situations. The actinides and strontium in air filter method utilizes a rapid acid digestion method and a streamlined column separation process with stacked TEVA, TRU and Sr Resin cartridges. Vacuum box technology and rapid flow rates are used to reduce analytical time. Alpha emitters are prepared using cerium fluoride microprecipitation for counting by alpha spectrometry. The purified (90)Sr fractions are mounted directly on planchets and counted by gas flow proportional counting. The method showed high chemical recoveries and effective removal of interferences. This new procedure was applied to emergency air filter samples received in the NRIP Emergency Response exercise administered by the National Institute for Standards and Technology (NIST) in April, 2009. The actinide and (90)Sr in air filter results were reported in less than 4 h with excellent quality.

Pattern of volatile aldehydes and aromatic hydrocarbons in the largest urban rainforest in the Americas

Atmospheric concentrations of aldehydes and monoaromatic hydrocarbons were determined in Tijuca Forest, the largest urban tropical forest in the Americas. The forest is a protected area, surrounded by the city of Rio de Janeiro. Data were also obtained in a commercial and a residential area for comparison. A total of 160 aldehyde samples and 60 BTEX (benzene, toluene, ethyl-benzene and xylenes) samples were collected from four locations between January and August of 2008. The aldehydes were collected using C18 resin cartridges coated with 2,4-dinitrophenylhydrazine and analyzed by high performance liquid chromatography (HPLC) with a diode array UV–Vis detector, while the BTEX samples were collected using tubes of coconut charcoal, which were then extracted with dichloromethane and analyzed by gas chromatography (GC). Within Tijuca Forest, formaldehyde and acetaldehyde levels were in the range of <detection limit – 5.09 ppbV and <detection limit – 4.08 ppbV, respectively. Formaldehyde concentrations strongly correlated with temperature and solar radiation. The different ratios for formaldehyde and acetaldehyde concentrations in the forest and in the urban sites clearly suggested that carbonyl levels within the forest might have an important contribution from biogenic sources. BTEX concentrations in the forest were very low, showing that the forest acted as a sink for many pollutants. Toluene/benzene ratios in the forest were also lower than in the city, which may be attributed to the faster photochemical oxidation of toluene. These observations were indicators of the low impact of the urban area on the studied forest.

Filtration et adsorption plasmatiques couplées : principe et perspectives dans le traitement du choc septique

Septic shock is the leading cause of multiple organ failure and mortality in intensive care units. This condition seems to be related to an overproduction of both pro- and anti-inflammatory mediators, leading to an immunological dysfunction. Therapeutic strategies aimed at reducing blood and tissue concentrations of these mediators have been developed. One of these techniques, based on extra-renal filtration, is called "coupled plasma filtration and adsorption".English and French language articles published between 1984 and 2008 were identified through a computerized Medline search. Keywords and MeSH terms used were: "coupled plasmafiltration", "coupled plasma filtration", "adsorption", "blood purification", "cytokines", "hemofiltration", "sepsis". Relevant publications were retrieved and scanned for additional sources. Nine publications were found.Coupled plasma filtration adsorption is an extra-corporeal treatment, based on non-specific cytokine adsorption on a specially designed resin cartridge, coupled with hemofiltration. Experimental studies and the first clinical trials have shown interesting results regarding hemodynamics and respiratory parameters. However, these trials failed to demonstrate any improvement in outcome.Additional evidence is needed to clarify the role of this blood purification technique for the treatment of septic shock.

Therapeutic approaches to reduce systemic inflammation in septic-associated neurologic complications

Treatment of severe sepsis and septic shock often focuses on resolving immediate life-threatening problems related to infection (source control, antibiotics) and providing circulatory, ventilatory and other organ support. Neurologic complications, such as sepsis-associated encephalopathy, frequently occur in septic patients and are associated with higher mortality and long-term complications. As case fatalities and overall mortality continue to decline, long-term cognitive problems are becoming more common among survivors. Although the aetiology of septic encephalopathy has not been clearly established, systemic inflammation appears to play a key role in altering both the blood-brain barrier permeability and amplifying the inflammatory response. Several new therapies are now aimed at reducing systemic inflammation. These may eventually play a role in reducing neurologic complications related to the acute pathophysiology of sepsis and may be able to reduce early cerebral dysfunction with the goal of reducing long-term neurologic complications. Coupled plasma filtration adsorption is an extracorporeal therapy aimed at the non-specific removal of cytokines and mediators involved in systemic inflammation and immune suppression by the use of plasma filtration coupled to an adsorbent resin cartridge with high affinity for many cytokines and mediators. Several cytokines that are removed by coupled plasma filtration adsorption have also been implicated in blood-brain barrier permeability, leucocyte recruitment and amplification of the inflammatory response. Current studies are ongoing to determine whether treatments such as coupled plasma filtration adsorption may also be beneficial in reducing long-term neurologic complications.

Rapid uranium preconcentration and separation method from fresh water samples for total U and 235U/ 238U isotope ratio measurements by ICP-MS

A simple and rapid method using TRU resin cartridges (Eichrom Technologies, Inc., USA) and quadrupole ICP-MS for total uranium (U) and 235U/ 238U isotope ratio measurements in fresh water samples was investigated. After U extraction on the resin by sample solution loading, three alkaline reagents, tetramethyl ammonium hydroxide (TMAH), NaOH and NH 4OH were studied for U elution behavior from the resin cartridges and applicability of these eluates was evaluated with respect to direct introduction to ICP-MS. Among the studied eluants, TMAH showed the best results with high U recovery and no counting interferences with internal standard elements such as thallium and bismuth. Moreover, U in water samples was separated from many major and minor elements with the TRU cartridges. Almost all U was concentrated in 10 mL of 0.014 M TMAH in 2 h using 200 mL of water sample.

A kit method for the high level synthesis of [ 211At]MABG

meta-[ 211At]Astatobenzylguanidine ([ 211At]MABG), an analogue of meta-iodobenzylguanidine (MIBG) labeled with the α-emitter 211At, targets the norepinephrine transporter. Because MABG has been shown to have excellent characteristics in preclinical studies, it has been considered to be a promising targeted radiotherapeutic for the treatment of tumors such as micrometastatic neuroblastoma that overexpress the norepinephrine transporter. To facilitate clinical evaluation of this agent, a convenient method for the high level synthesis of [ 211At]MABG that is adaptable for kit formulation has been developed. A tin precursor anchored to a solid-support was treated with a methanolic solution of 211At in the presence of a mixture of H 2O 2/HOAc as the oxidant; [ 211At]MABG was isolated by simple solid-phase extraction. By using C-18 solid-phase extraction, the radiochemical yield from 25 batches was 63 ± 13%; however, loss of radioactivity during evaporation of the methanolic solution was a problem. This difficulty was avoided by use of a cation exchange resin cartridge for isolation of [ 211At]MABG, which resulted in radiochemical yields of 63 ± 9% in a shorter duration of synthesis. The radiochemical purity was more than 90% and no chemical impurity has been detected. The final doses were sterile and apyrogenic. These results demonstrate that [ 211At]MABG can be prepared via a kit method at radioactivity levels anticipated for initiation of clinical studies.

Characterization of the coupled plasma filtration–adsorption resin cartridge adsorptive capacity for cytokines and inflammatory mediators: adsorption profiles from septic patient plasma and in vitro endotoxin-stimulated whole blood

Coupled plasma filtration–adsorption (CPFA) is an extracorporeal therapy that uses plasma filtration associated with an adsorbent cartridge and hemofiltration in postdilution to remove cytokines and inflammatory mediators associated with septic shock and severe sepsis. We evaluated the adsorptive capacity of the resin cartridge to remove various inflammatory mediators and cytokines in vitro and ex vivo.

Rapid method for 226Ra and 228Ra analysis in water samples

The measurement of radium isotopes in natural waters is important for oceanographic studies and for public health reasons. Radium-226 (T1/2 = 1620 y) is one of the most toxic of the long-lived alpha-emitters present in the environment due to its long life and its tendency to concentrate in bones, which increases the internal radiation dose of individuals. The analysis of 226Ra and 228Ra in natural waters can be tedious and time-consuming. Different sample preparation methods are often required to prepare 226Ra and 228Ra for separate analyses. A rapid method has been developed at the Savannah River Environmental Laboratory that effectively separates both 226Ra and 228Ra (via 228Ac) for assay. This method uses MnO2 Resin from Eichrom Technologies (Darien, IL, USA) to preconcentrate 226Ra and 228Ra rapidly from water samples, along with 133Ba tracer. DGA ResinO (Eichrom) and Ln-ResinO (Eichrom) are employed in tandem to prepare 226Ra for assay by alpha-spectrometry and to determine 228Ra via the measurement of 228Ac by gas proportional counting. After preconcentration, the manganese dioxide is dissolved from the resin and passed through stacked Ln-Resin-DGA Resin cartridges that remove uranium and thorium interferences and retain 228Ac on DGA Resin. The eluate that passed through this column is evaporated, redissolved in a lower acidity and passed through Ln-Resin again to further remove interferences before performing a barium sulfate microprecipitation. The 228Ac is stripped from the resin, collected using cerium fluoride microprecipitation and counted by gas proportional counting. By using vacuum box cartridge technology with rapid flow rates, sample preparation time is minimized.

Impacts of gloving and un-mixed resin in fully encapsulated roof bolts on geotechnical design assumptions and strata control in coal mines

Modern strata control practices utilising resin encapsulated roof bolts has been adopted in high productivity coal mining operations as the primary means of reinforcement. The geotechnical design of safe and fit-for-purpose underground excavations relies on many design assumptions regarding the effectiveness and load transfer characteristics of the installed reinforcement. The effectiveness of the installed roof bolts can be compromised by glove fingering (gloving) of the resin cartridge and un-mixing of the resin mastic, resulting in a reduction in the load transfer characteristics of the roof bolts, and ultimately, compromising the design assumptions used. Following a routine installed bolt quality audit and some small roof falls containing gloved bolts across a range of mine sites involving many geological and geotechnical conditions, a work programme was initiated to determine the extent of the gloving and un-mixing problem and to develop an understanding of mechanisms involved. Results have shown that gloving and un-mixing is a systematic and widespread phenomena, occurring across the range of resin and/or bolt manufacturers, and in a variety of roof types. Gloving was found in bolts installed using either hand held pneumatic or continuous miner-mounted hydraulic bolting rigs, under face conditions by operators, and under controlled manufacturers “best practice” conditions. Research has been undertaken using recovered bolts from various mine sites, as well as test bench trials and the quantification of the loading characteristics of gloved bolts using strain-gauged roof bolts. To understand the impacts of gloved bolts and un-mixed resin on the geotechnical design assumptions used a FLAC 2D numerical simulation was undertaken. The results provided an insight into the way the roof bolts interact, the resultant failure mechanisms/pathways and provided quantification of deformation levels and reinforcement requirements. The results being incorporated into the strata management plans.

Effects of Fluid Composition on Mist Composition

In a reported study, mists of selected synthetic metalworking fluids were generated in laboratory experiments by two processes, nebulization (atomization) and air sparging (bubbling). Short-chain fatty acid species were determined by in situ trimethylsilyl derivatization. Comparison of relative amounts of the short-chain acids collected from mists generated by nebulization with those generated by sparging showed that the sparged mists had significantly higher amounts of neodecanoic, nonanoic, and dodecanedioic acids. Comparison of the amounts of acids collected by the resin cartridges to amounts found on the filters showed that significant losses of octanoic and isononanoic acids occurred over 8 hours of collection and that only dodecanedioic acid was not lost from the filter over a 22-hour sampling period. In another reported metalworking mist study, contaminants of metalworking fluids, e.g., tramp oils, were shown in laboratory experiments to increase the misting potential of water-based metalworking fluids. Significantly, tramp oil contamination caused less misting in synthetic fluids than soluble and semi-synthetic fluids.

Tantalum [ 18O]Water Target for the Production of [ 18F]Fluoride with High Reactivity for the Preparation of 2-Deoxy-2-[ 18F]Fluoro-D-Glucose

Purpose: To develop a new tantalum [ 18O]water target for the routine production of reactive, no-carrier-added [ 18F]fluoride ion in Curie amounts for the synthesis of radiopharmaceuticals. Procedures: The tantalum target body was filled with 0.86 mL of 95% enriched [ 18O]water and irradiated with 10.2 MeV protons on target with beam currents of 26–40 μA for 60–90 min. [ 18F]Fluoride ion produced is trapped in an anion exchange resin cartridge and the expensive [ 18O]water is recovered for recycling. The [ 18F]fluoride ion is released from the resin by elution with a dilute solution of K 2CO 3 and utilized in the synthesis of 2-deoxy-2-[ 18F]fluoro-D-glucose (FDG). Results: Using the tantalum target, Curie levels of no-carrier-added [ 18F]fluoride ion (specific activity: >30,000 Ci/mmol) were reliably and reproducibly produced ( n > 100), from which FDG was synthesized in 70% radiochemical yield. Conclusion: Tantalum [ 18O]water target body for the production of [ 18F]fluoride ion has the best characteristics from the standpoint of [ 18F]fluoride ion recovery and its radiochemical reactivity and low induced activation. This new target has the potential to replace the currently used silver and titanium [ 18O]targets for the routine production of [ 18F]fluoride ion. (Mol Imag Biol 2002;4:65–70)

A rapid sequential separation of actinides using Eichrom's extraction chromatographic material

For the past 10 years, Eichrom has provided a variety of innovative products for faster separation of radionuclides to radioanalytical laboratories. However, recently, environmental testing laboratories have been challenged to generate reliable data more quickly. To assist our customers with rapid separations, Eichrom has developed a new configuration for its existing extraction chromatographic material that operates with vacuum assisted flow. After pre-concentration of actinides from a given sample, the actinides are dissolved in a suitable solution. Appropriate Eichrom Resin Cartridges are placed on a vacuum box system. Sample solutions are then passed through the cartridges under optimal vacuum pressure. In this paper, a scheme for separation of actinides in different matrices are discussed using Eichrom Resin Cartridges. Time required for separations, test results and ease of use are the primary discussions of this paper.

Duplicate sampling reproducibility of atmospheric residues of herbicides for paired pan and high-volume air samplers

The reproducibility of collection of atmospheric residues of the herbicides 2,4-D and triallate as bulk (wet plus dry) deposition samples by paired pan samplers and as particulate (filter) and vapour (PUF/XAD-2 resin cartridge) samples by paired high-volume air samplers was determined. Variability of herbicide concentrations in paired bulk deposition samples was within 25% for 65 and 80% of the samples for 2,4-D and triallate, respectively, with approximately 90% of the paired samples being within a factor of 2 for both herbicides. The vapour samples of 2,4-D and triallate showed similar reproducibilities. The highest reproducibility was observed for the filter samples with 92% of the paired data sets for 2,4-D being within 25% variability. No triallate was detected in the filter samples.

Determination of the main hydrolysis products of organophosphorus nerve agents, methylphosphonic acids, in human serum by indirect photometric detection ion chromatography

For the verification of the use of chemical warfare agents (CWA), sarin, soman and VX, a simple rapid and accurate method which allows us to simultaneously determine their degradation products, isopropyl methylphosphonic acid (IPMPA), pinacolyl methylphosphonic acid (PMPA), ethyl methylphosphonic acid (EMPA) and methylphosphonic acid (MPA), in human serum, was explored by indirect photometric detection ion chromatography (IPD-IC) which employs an anion-exchange column. IC analysis was performed after sample preparation with an Ag + -form cation-exchange resin cartridge, and the four methylphosphonic acids could be separated well. The proposed conditions are as follows: eluent, 0.5 m M phthalic acid-0.1 m M Tris (hydroxymethyl) aminomethane-5% acetonitrile; flow-rate, 1.0 ml/min; temperature, 50°C; UV detector, 266 nm. All four methylphosphonic acids were eluted within 30 min with hardly any disturbance by impurities in the serum. Linear calibration curves were obtained for MPA, EMPA and IPMPA in the concentration range from 50 ng/ml to 1 μg/ml and for PMPA from 100 ng/ml to 1 μg/ml. The relative standard deviation for the methylphosphonic acids ranged from 3.8 to 6.9% at 500 ng/ml and the detection limits were 40 ng/ml for MPA, EMPA and IPMPA and 80 ng/ml for PMPA. The method would be suitable for analysis of human serum samples.

Polychlorinated dibenzofurans and dibenzo-p-dioxins in subsurface soil, superficial dust, and air extracts from a contaminated landfill.

Extracts of soil, dust and air from a National Priorities List Landfill have been found to contain distinct profiles of polychlorinated biphenyls (PCBs). The different extracts show subtle differences in toxicities and the soil extract has been shown to cause both Ah receptor mediated effects and Ah receptor independent effects in immature female rats. Evidence of open burning at the site dictated quantitation of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) for a more accurate tabulation of dioxin equivalencies. High volume air sampling on XAD-2 resin cartridges captured trace amounts of PCDFs and no detectable PCDDs. Acetone:Hexane (1:1) extracts of soil and dust contained 762 microg/ml and 250 microg/ml PCDFs, respectively, and less than 10% as much PCDD. Subsequent benzene:methylene chloride (1:1) extracts were enriched in coplanar compounds relative to total PCBs. PCDF:PCB ratios in all extracts were higher than in the rice oils contaminated with heated PCBs in the Yusho and Yu-Cheng incidents. No 2,3,7,8-TCDD was detected, and total PCB+PCDD+PCDF toxic equivalencies were dominated by the high proportions of PCDFs.

Mechanism of peptide separations by solid phase extraction capillary electrophoresis at low pH.

A device for on-line extraction and concentration of peptides from a dilute sample matrix prior to direct capillary electrophoretic analysis is described. The technique, termed solid phase extraction capillary electrophoresis (SPE-CE), can facilitate analysis of peptides in the low nanograms per milliliter range. Peptides from a sample matrix are adsorbed on a reversed phase resin (C-8 or C-18) cartridge in-line with an uncoated fused-silica capillary and subsequently released for free zone electrophoresis by injection of an organic elutant. Unlike previous designs and commercially available packed-inlet capillaries, the device is easily constructed from common laboratory materials and is applicable to a wide range of conventional instrumentation and methods. This device and method has been developed for use in our laboratory as a stand-alone preparative technique, specifically to provide a second-dimensional orthogonal separation of biologically derived HPLC fractions of peptides in a single analysis. To this end, extensive effort was required in both device construction and method development to attain the successful separations which are reported in this study. Extractions of dilute peptide mixtures from sample injections exceeding, but not limited to, 20 times (48 microL) the capillary volume with apparent recovery greater than 80% are shown. The selectivity of extraction of individual components of a very dilute peptide mixture (31 ng/mL with 280 microL of sample injected) is presented. The ability to efficiently extract the individual peptides from the sample was found to be concentration-dependent for the individual peptide components over a 1600-field dilution of a common calibration mixture of nine model peptides. Varying the injected volume of elution buffer demonstrated the importance of minimizing the amount of buffer used to desorb peptides to maximize the resolution of individual peptides. This study highlights implementation for direct SPE-CE for peptide analysis and discusses for SPE tip-induced mechanism through which reversal in electoosmotic flow occurs.

Rapid method for determination of phenylurea herbicides in milk

A method has been developed for the determination of thirteen phenylurea herbicide residues in milk. It involves one-step solvent extraction of the milk with methanol by ultrasonication. The extract is cleaned up on an Amberchrom resin cartridge. Reversed-phase, gradient elution, high-performance liquid chromatography with UV detection at 242 nm is used to analyse the residues. The recovery of thirteen phenylurea pesticides is quantitative, ranging from 71.4% to 97.9% for the individual herbicides investigated at concentrations around 0.05 mg kg−1 and from 65.1% to 95.6% around 0.005 mg kg−1. The method is not associated with any of the emulsion problems common to conventional solvent extraction, which considerably reduce the sample clean-up process compared with existing methods.

Monitoring of polycyclic aromatic hydrocarbon emissions from biomass combustion in Kenya using liquid chromatography with fluorescence detection

Sampling and reversed-phase liquid chromatographic analysis with fluorescence detection of polycyclic aromatic hydrocarbons (PAHs) released from biomass combustion sources is presented. PAH emissions from charcoal obtained from Acacia mearnsii and Newtonia buchananii trees, combusted in two charcoal burning stoves commonly used in Kenya (traditional metal and ceramic-lined) are compared. Particulate bound and gaseous PAH were sampled onto a glass microfibre filter and an XAD-2 resin cartridge, respectively. PAH results from samples collected in kitchens in the Kenyan Highlands are also presented and discussed in relation to indoor air pollution in developing countries.