Ion-exchange Filter Paper Research Articles

Assessment of two types of passive sampler for the efficient recovery of SARS-CoV-2 and other viruses from wastewater

Wastewater-based epidemiology (WBE) has proven to be a useful surveillance tool during the ongoing SARS-CoV-2 pandemic, and has driven research into evaluating the most reliable and cost-effective techniques for obtaining a representative sample of wastewater. When liquid samples cannot be taken efficiently, passive sampling approaches have been used, however, insufficient data exists on their usefulness for multi-virus capture and recovery. In this study, we compared the virus-binding capacity of two passive samplers (cotton-based tampons and ion exchange filter papers) in two different water types (deionised water and wastewater). Here we focused on the capture of wastewater-associated viruses including Influenza A and B (Flu-A & B), SARS-CoV-2, human adenovirus (AdV), norovirus GII (NoVGII), measles virus (MeV), pepper mild mottle virus (PMMoV), the faecal marker crAssphage and the process control virus Pseudomonas virus phi6. After deployment, we evaluated four different methods to recover viruses from the passive samplers namely, (i) phosphate buffered saline (PBS) elution followed by polyethylene glycol (PEG) precipitation, (ii) beef extract (BE) elution followed by PEG precipitation, (iii) no-elution into PEG precipitation, and (iv) direct extraction. We found that the tampon-based passive samplers had higher viral recoveries in comparison to the filter paper. Overall, the preferred viral recovery method from the tampon passive samplers was the no-elution/PEG precipitation method. Furthermore, we evidenced that non-enveloped viruses had higher percent recoveries from the passive samplers than enveloped viruses. This is the first study of its kind to assess passive sampler and viral recovery methods amongst a plethora of viruses commonly found in wastewater or used as a viral surrogate in wastewater studies.

Determination of 135Cs concentration and 135Cs/137Cs ratio in waste samples from nuclear decommissioning by chemical separation and ICP-MS/MS

Determination of 135Cs concentration and 135Cs/137Cs atomic ratio is of great importance in characterization of radioactive waste from decommissioning of nuclear facilities. In this work, an effective analytical method was developed for simultaneously determination of 135Cs and 137Cs in different types of waste samples (steel, zirconium alloy, reactor coolant, ion exchange filter paper and spent ion exchange resin) by coupling AMP-PAN, AG MP-1M and AG 50 W-X8 chromatographic separation with ICP-MS/MS measurement. Decontamination factors of 7.0 × 106 for Co, 6.0 × 106 for Ba, 4.2 × 105 for Mo, 3.2 × 105 for Sn and 2.1 × 105 for Sb were achieved using the chemical separation procedure. The overall chemical yields of cesium were higher than 85%. A detection limit of 3.1 × 10−14 g/g for 135Cs was achieved for 0.2 g stainless steel sample or spent resin. The developed method was validated by analysis of standard reference materials (IAEA-375) and successfully applied for analysis of zirconium alloy, steel, ion exchange filter paper and spent ion exchange resin from nuclear power reactors. The obtained 135Cs can be used to evaluate the long-term environmental impact and provide useful information for waste disposal. The measured 135Cs/137Cs ratio in reactor coolant, as a characteristic information, might be useful for source identification and localization of leaked fuel element. The neutron flux of the leaked fuel element can be estimated based on the measured 135Cs/137Cs atomic ratios in the reactor coolant water. The developed method is simple and rapid (8 samples/day) for the determination of 135Cs concentrations and 135Cs/137Cs ratios in various waste samples from nuclear decommissioning.

Correlation between clinicopathologic factors and kinetics of metabolic enzymes for 5-fluorouracil given to patients with colon carcinoma by two different dosage regimens.

Using tumor tissue specimens from colon carcinoma patients given 5-fluorouracil (5-FU) by two different administration methods, we investigated the degree of correlation between clinicopathologic factors and the kinetics of metabolic enzymes for 5-FU. Group A patients received 500 mg/day of 5-FU as a rapid infusion over 2 h for 3 days preoperatively, and group B patients received 500 mg/day of 5-FU as a continuous infusion for 3 days preoperatively. The activities of orotate phosphoribosyl transferase (OPRT), thymidine phosphorylase (TP), uridine phosphorylase (UP), and dihydropyrimidine dehydrogenase (DPD) were measured by separation on ion-exchange filter paper, by high-performance liquid chromatography (HPLC) with UV detection and by HPLC with radioactive flow monitoring, respectively, and the [(3)H]-5-fluorodeoxyuridine monophosphate binding site in thymidylate synthetase (TS) was determined as an index of the amount of TS using a radiobinding assay. The TS inhibition rate (TSIR) was calculated from the formula: 1-(TS(free)/TS(total))x100. Finally, 5-FU incorporation into RNA (FRNA) was measured by capillary gas chromatography-mass spectrometry. In group A patients, FRNA showed a positive correlation only with OPRT, and TSIR showed positive correlations with OPRT and TP, but a negative correlation with TS. In group B patients, FRNA showed a negative correlation with DPD, and TSIR showed a negative correlation with TS. No difference in TSIR levels was seen between groups A and B. FRNA was higher in group A than in group B, but the difference was not statistically significant. The method of administration may influence 5-FU metabolism in colon carcinoma patients.

PIXE Analysis of Trace Heavy-Metals in River Waters Using an Ion-Exchange Cellulose Filter Paper

A simple but precise method for the PIXE analysis of trace heavy-metals in aqueous samples was developed, in which the PIXE targets were prepared by pre-concentrating heavy metals on a cellulose phosphate ion-exchange filter paper and no additional chemical treatment was required. Heavy metals in trace concentrations were quantitatively retained up to 16.7 μ-equivalent on a sheet of filter paper due to the excellent selectivity for heavy metals and ion-exchange kinetics of phosphate groups in cellulose matrix. Heavy metals of less than 1 μg on one filter paper are precisely and rapidly determined by PIXE analysis using 3-MeV proton beams. The present method is compared with the method preparing a PIXE target for each dissolved species of an element contained in aqueous samples. It will be resulted that the newly developed method enables an on-line PIXE analysis for river waters.

Study of ph and substrate effects on room-temperature phosphorimetry of some indolecarboxylic acids

Room-temperature phosphorescence (RTP) of eight indolecarboxylic acids has been investigated under different pH conditions, and on several ion-exchange filter papers. RTP excitation and emission wavelengths do not change significantly with pH. The largest RTP signals are obtained from neutral solutions adsorbed on DE-81 anion-exchange filter paper, while alkaline (pH ~ 13) solutions on S & S 903 filter paper treated with DTPA (diethylenetriaminepenta-acetic acid) give stronger signals than neutral or acidic (pH ~ 1.6) solutions on the same substrate. The existence of several hydrogen-bonding interactions between the various ionic indolecarboxylic acid species and the substrates is discussed. Heavy-atom enhancement factors ranging between 4 and 550, according to the compound, are obtained with iodide. Absolute limits of detection between 100 and 500 pg demonstrate the usefulness of RTP for determination of indolecarboxylic acids at the trace level.

Atomic absorption spectrometry of silver collected on ion-exchange filter paper by directly heating the filter paper.

In this paper direct determination of silver collected on ion-exchange filter paper was studied. 50 ml of sample solution of which pH was adjusted to 3.3 with hydrochloric acid was passed through a sheet of ion-exchange filter paper, and after the filter paper was dried, it was punched with a 2.5 mm puncher. The small tablet was put onto a tungsten atomizing furnace and electrothermally heated. The calibration curve was linear at Ag+ concentrations below 0.3 ng/ml, and 1% absorption sensitivity was 1.2×10-3 ng/ml. Coexsisting 104-fold Na+, 103-fold Cu2+, and 103-fold Pb2+ did not affect the absorbance of Ag. Detection limit of this method is considered to lower by increasing the volume of sample solution.

The effects of ion-exchange filter papers and of heavy atoms on room-temperature phosphorescence of several indoles

Room-temperature phosphorescence (r.t.p.) of twelve indoles on different ion-exchange filter papers is examined. Anion-exchange filter paper Whatman DE-81 gives the largest r.t.p. signals in the presence of iodide; S & S 903 paper treated with diethylenetriamine-pentaacetic acid or supported carboxymethylcellulose resin are less useful. The heavy atom effect is necessary to observe analytically useful r.t.p. signals of indoles, with the trend iodide > thallium(I). Lifetimes of the r.t.p. of indoles are very short, in the millisecond range, and show two components. Absolute limits of detection between 0.2 and 14 ng show r.t.p. to be sensitive and simple analytical technique for these compounds.

A rapid spot test for urinary methylmalonic acid collected on ion-exchange filter paper

We developed a rapid, accurate method to detect pathologic amounts of methyl-malonic acid (MMA) in urine samples, which can be applied to simplify and improve the accuracy of screening for methylmalonic acidemia. Urine is collected on DEAE-cellulose paper and air-dried. Six mm discs are punched from the dried paper and placed in a multi-well tray; non-anionic substances interfering with the assay are rinsed from the discs; and a color reaction using diazotized p-nitroaniline is carried out in situ on the disc. Of 407 urine samples blindly tested, all 83 samples from nine patients with methylmalonic acidemia gave positive results. None of the other urine specimens from normal individuals or patients with a variety of organic acidemias gave positive results. This method should allow accurate and inexpensive mass screening for methylmalonic acidemia in newborn or infant screening programs.

A rapid assay for Escherichia coli 4-thiouridine-tRNA sulfurtransferase

A simple filter paper assay for the measurement of Escherichia coli 4-thiouridine-tRNA sulfurtransferase activity is described. The assay includes the following procedures: (a) incubation of enzyme with appropriate substrates including unfractionated yeast tRNA and [ 35S]cysteine, (b) reisolation of tRNA, and (c) binding of tRNA to ion exchange filter papers. The assay can be routinely performed with relatively small sample volumes (0.1 ml) and completed within 14 h. Proof of the validity of the assay is based in part on two experimental observations: (1) tRNA is the predominant 35S-labeled species remaining bound to the filter after extensive washing, and (2) 4-thiouracyl is the predominant thiolated base formed during the assay.

Application of a Single Element X-Ray Fluorescence System to Routine Analysis of Ionized Calcium and Strontium in Water

A very simple and rapid method was developed, for the analysis of trace elements in water, based on the radioisotopic excited X-ray fluorescence. The method requires the filtration of the water through an ion exchange filter paper, which is successively dried and XRF analyzed. The analysis of ionized calcium and strontium in mineral waters were carried out.

Determination of Lead in Dinnerware by an Ion Exchange Filter Paper ‐ X-Ray Fluorescence Method

Abstract Lead leached from a variety of pottery dinnerware was determined by x-ray fluorescence after collecting and concentrating the lead on an ion exchange resin loaded filter paper disc. A 0.01 M HCl solution, to simulate acidic foodstuffs, used for the leaching was shown to have a leaching rate almost identical to that of white vinegar. The leaching rate increased with increasing temperature. The relative standard deviation for successive determinations of the same lead content was 1.8%, and the detection limit was 1.08 μg of total lead which corresponded to 0.0072 ppm when 150 ml of leaching solution was used.

Activation analysis of heavy metals in surface waters using ion exchange filter papers and cyanide complexing

This paper describes a simple, reasonably rapid, and accurate technique developed for the multielement analysis of heavy metals in surface waters using ion exchange filter papers and cyanide complexing in conjunction with neutron activation analysis. The method employs large water volume irradiation for improved sensitivity.130Te was used as an internal flux monitor to correct for neutron flux variations in the samples. Proof of the value of this technique was obtained by the analysis of 10 surface water samples previously analyzed using conventional methods by the U. S. Geological Survey of the U. S. Department of Interior. Good agreement resulted from this comparison.

USE OF X‐RAY FLUORESCENCE TO DETERMINE TRACE METALS IN WATER RESOURCES1

ABSTRACT. The X‐ray fluorescence method was used to analyze trace metals collected in particulate form on filter papers and from the ionic state by ion exchange filter papers. The samples were prepared by allowing water to pass through these filter papers. The procedures necessary for using the X‐ray fluorescence method are described. A number of samples were taken from the Great Miami River in Dayton, Ohio over one year showing the presence of the following metals, Ca, Ti, Cr, Fe, Cu, Zn, Sr, and Cd. Elements in the periodic table between Ti and Cs were detectable to a sensitivity limit of the order of 30 ppb for metals in the particulate form and 0.4 ppm for metals in the ionic form.

Ion exchange filter paper holder for x-ray spectrometry

Ion exchange filter paper holder for x-ray spectrometry

Two-dimensional electrochromatography of 106ruthenium and some other radiomicroconstituents in sea water.

Abstract Two-dimensional electrochromatography on filter paper sheets and filter paper sheets loaded with ion-exchange resins, of 106 Ru and some other microconstituents using sea water as a background electrolyte are described. The results are developed by radioautography on an X-ray film. Some of the microconstituents, 51 Cr as chromate, 22 Na, 54 Mn, 56,57,58 Co, 90 Sr, 65 Zn and 90 Y, showed no, or a slight, adsorption on filter paper and each of them gave one single mobile fraction. The others were strongly adsorbed on filter paper at the starting point, as 51 Cr, 59 Fe, 95 Nb, 95 Zr, 144 Ce, 147 Pm and 181 Hf, presumably because of the formation of strongly adsorbable hydrolytic species or particle formation. Samples of 106 Ru from Amersham in chloride form (original in 8 M HCl), and in nitrate from (original in 8 M HNO 3 ), were used after a preliminary treatment. Experimental evidence shows that, in sea water, 106 Ru behaves very differently, depending on the form of the original sample (chloride or nitrate form). The two-dimensional electrochromatography of 106 Ru in sea water showed a relatively large number of well-defined species which could be readily classified into anionic, cationic, electroneutral, particulate, non-adsorbable and more or less adsorbable species on filter paper. Although anionic fractions, as expected, were strongly adsorbed on anion ion-exchange paper (Dowex 2-X8), cationic fractions of ruthenium in chloride form were not adsorbed on cation ion-exchange filter paper (Dowex 50). The same experiments were also performed starting from RuO 4 , which was obtained by a distillation method. The fate of RuO 4 and soluble species resulting from decomposition of the tetroxide in HCl and HNO 3 solutions and in sea water, was studied.