Calibration Curve Method Research Articles

The Analysis of Total Dissolved Iron from Mud Sedimentation Ponds Wastewater in PT Bukit Asam (Persero) Tbk Tanjung Enim Using Individual Control Diagram

The tests have been carried out on the iron content of wastewater in the inlet and outlet of the mud sedimentation ponds PT Bukit Asam (Persero) Tbk Tanjung Enim, South Sumatra Province. The iron concentration in mining waste water that does not comply with government standards of 7.0000 mg / L can pollute the environment. The measurement of iron concentration was carried out by Atomic Absorption Spectrophotometer (AAS) method in accordance with SNI 06-6989.4: 2004. Analysis of iron concentration using calibration curve methods and individual control diagrams. The results of data analysis showed that the iron content of the inlet and outlet MSP (Mud Sedimentation Ponds) wastewater was still under the standard set with an average value of 1.4488 mg/L inlet and outlet 0.4061 mg/L. Based on the results of the study the concentration of iron meets the established quality standards.

Determination of Prussian Blue Nanoparticles in Rat Tissue in the Presence of Endogenous Iron Interferences by Inductively Coupled Plasma – Optical Emission Spectrometry (ICP-OES)

A modified calibration curve method based on the combination of standard addition and traditional calibration curve methods was employed for the quantification of Prussian blue nanoparticles in rats in the presence of endogenous iron interferences. The assay was performed using inductively coupled plasma – optical emission spectrometry (ICP-OES) with yttrium as the internal standard, and validated in biomatrices including liver, heart, kidneys, lungs, spleen and whole blood. For the liver tissue, the intra-day and inter-day precision were 7.84% or less, and the accuracy was between 99.88% and 102.37%. For kidneys, lungs, heart, spleen, and blood, at each exo-additive level from 0.4 to 3.2 µg/mL, the intra-day accuracy was between 98.74% and 102.09%, and the intra-day precision was 6.17% or less. For the addition of no analyte, the intra-day accuracy was between 96.42% and 107.52%, and the intra-day precision was 15.67% or less. The stability was investigated at 25 °C for 24 h and 4 °C for 15 days in liver standard addition samples, and no significant degradation occurred under these conditions. This method was successfully applied to the preliminary pharmacokinetics and tissue distribution study of Prussian blue nanoparticles in rats. This approach may also be applied to the quantification of other ferruginous materials in the biological matrices with endogenous iron.

Evaluation of photoluminescence from milk with various vitamin B2 concentrations

Concentrations of vitamin B2 in milk were evaluated based on photoluminescence (PL) peak intensities at around λ = 545 nm. PL was measured in a back-scattering configuration using a 3.2 mm diameter optical fibre bundle irradiated by ultra-violet LEDs, violet LEDs or a blue LED as the excitation light. The tip of the optical fibre bundle was dipped into commercially available whole milk, low-fat milk and non-fat milk. PL peaking at 545 nm was observed under LED irradiation. Vitamin B2 concentrations were measured using a standard addition method and a calibration curve method. Deviation between the vitamin B2 concentration measured by PL using a standard addition method and those by HPLC technique varied with wavelength of excitation light and was smallest with violet LED (405 nm) excitation. The standard deviation of results measured by PL using a calibration curve method was better than those using a standard addition method.

Propylene Oxide−Ethylene Oxide Block Polymer as a Surfactant for Cloud Point Extraction of Some Metal Ions

Propylene oxide-ethylene oxide block polymer (PO-EO) is a surfactant with low cloud point. It has been used for separation of Cu2+, Fe3+, Mn2+, Cd2+ and Cr3+ ions in aqueous media. The effect of different factors on recovery percent, like pH, temperature, amount of chelating agent, and amount of surfactant have been studied. A very good separation of metal ions could be achieved at different pH values with good effeciency of separation under the optimum conditions. The analyses of metal ions were carried out using flame atomic absorption spectrometer with duterium lamp background correction and calibration curve method curve method.

Fabrication and evaluation of potentiometric sensors of an anticancer drug (Gemcitabine)

Accurate, rapid and inexpensive determination of gemcitabine, an anticancer drug, is of high interest. This manuscript describes the use of potentiometric sensors as a basis for this work given their known attractive characteristics that meet our needs. Potentiometric sensors were comprised of carbon paste S1, coated wire S2 and PVC membrane S3, of gemcitabine (an anticancer drug) were fabricated, studied and evaluated. The calibration plots for these electrodes showed a Nernstian slope of 58.4±0.3, 59.5±0.3 and 58.3±0.3 mV per decade with the limit of detection: 6.50×10-5, 7.20×10-5 and 4.60×10-5 for sensors S1, S2 and S3, respectively. The electrodes have a short and stable response time of ~5 seconds and good reproducibility in a pH range of 2.5-9.5. The present sensors show distinct selectivity toward the drug ion in comparison to several inorganic ions, sugars, amino acids and some common drug excipients. Gemcitabine was determined successfully in ampoules and urine using these sensors by the calibration curve method.

New procedures of Metronidazole determination by the method of Gas-Liquid Chromatography

Metronidazole is the most popular representative in the group of medicines of 5-nitroimidazole derivatives. Based on the information about metronidazole side effects and its interaction with alcohol it is a potential analyte in forensic toxicology. The purpose is to develop GLC-procedures of metronidazole quantification and carry out their step-by-step validation to choose the optimal variant for further application in analytical toxicology. The chromatographic conditions has been chosen for metronidazole determination by the method of gas-liquid chromatography in two variants of performance with flame-ionization and mass-spectrometry detection with temperature program changing during the analysis from 70°C to 250°C or 320°C respectively. The GLC/FID-analyses were performed using gas chromatograph HP 6890 Hewlett Packard; column – HP-1 Q0.32mm × 30 m, 0.25μm, 100% dimethylpolysiloxane. The GLC/MSD-analyses were performed using Agilent 6890N Gas Chromatograph; columns – 1) HP-5MS Q0.25mm × 30m, 0.25μm, 5% diphenylpolysiloxan/95% dimethylpolysiloxan; 2) DB-17MS Q0.25mm × 30m, 0.15μm, 50% diphenylpolysiloxan/50% dimethylpolysiloxan; columns are connected sequentially through Deans switch. Under proposed conditions metronidazole and four other 5-nitroimidazole derivatives (tinidazole, ornidazole, secnidazole, nimorazole) are separated and detected without preliminary derivatization. In the method of GLC/FID the retention time for metronidazole is 9.08 min, in the method of GLC/MSD – 12.01 min. New GLC-procedures of metronidazole quantitative determination under proposed conditions have been developed. Their validation by such parameters as stability, linearity, accuracy and precision in the variants of the method of calibration curve, method of standard and method of additions has been carried out and acceptability for application has been shown.

Determination of Bi in complex oxide samples by atomic absorption spectrometry by using ordinary acetylene – air flame atomization

In the present work the air/acetylene flame atomic absorption spectrometry was used for bismuth determination in complex oxides. Interference studies were carried out, and interference with vanadium and molybdenum was detected. The method of standard additions and traditional calibration curve method were used. Calibration and standard addition curves were fitted with linear and polynomial functions. It was shown that using polynomial function gives better results for the standard additions method for determination of bismuth by acetylene/air flame atomic absorption spectrometry. The calibration curve method was shown to be correct at low ( 10mg/L) concentration of an interferent.

Measurement of PuO2 film thickness by electron probe microanalysis (EPMA) calibration curve method

Plutonium (Pu) surfaces are highly reactive toward oxygen containing species and, therefore, invariably covered with oxides (e.g. PuO2) during transport and handling. The actual thickness of the surface oxide may dictate if a plutonium part is suitable for a certain application. As a result, a cost-effective, quick, non-destructive, yet reliable means to measure the oxide layer thickness formed on Pu samples is desirable. In this study, the cross-sections of a series of room temperature grown oxides on Pu samples were trenched by focus ion beam (FIB) then observed by scanning electron microscopy (SEM) to measure the surface oxide thicknesses, which were then combined with the corresponding oxygen k-ratios provided by electron probe microanalysis (EPMA) to form calibration curves. Oxide thickness measurements for the calibration curves were made on samples within the typical SEM observable range for PuO2 (35–400 nm). The portion of the calibration curve in the thinner oxide region (<35 nm) were approximated via Pouchou and Pichoir’s ϕ(ρz) theory. Two specimens with micrometer-thick PuO2 standards (one formed at room temperature and the other at higher temperature with a higher level of crystallinity) were made for the k-ratios in this study, allowing EPMA users to choose the standard that best suits their needs. If the surface corrosion is known to be PuO2 (from the environment in which the Pu sample is stored) or if the stoichiometry of the surface oxide is confirmed by a preliminary/compliment technique, these calibration curves allow EPMA users to quickly and efficiently determine PuO2 thicknesses from the measured oxygen k-ratios of their samples. The methodology presented in this study can also be used as a template for creating calibration curves for oxides grown on other actinides.

Quantitative Analysis of Piperine and the Derivatives in Long Pepper Extract by HPLC Using Relative Molar Sensitivity

A novel method was developed for quantification of five major piperine derivatives (piperanine, piperine, chavicine, isopiperine, and isochavicine) in a hot water extract of long pepper fruit (LPE) using the relative molar sensitivity (RMS) based on the combination of HPLC/UV and 1H- quantitative NMR (1H-qNMR). The RMSs of piperanine, chavicine, isopiperine, and isochavicine to piperine of which the absolute purity was determined by 1H-qNMR were calculated to be 0.3693, 1.138, 0.9164, and 1.277, respectively. The total amount of piperine derivatives in LPE was quantified by both 1H-qNMR and HPLC/UV based on the RMS using piperine as a single-reference material (RMS method). The relative difference in quantitation values of 1H-qNMR and calibration curve method from the RMS method was 2.01% or less. The relative difference of the total cis-trans piperine isomers content between before and after photoirradiation in piperine solution was quantified to be 2.84% by the RMS method. In addition, the interlaboratory difference of the RMS method was confirmed in the range of 0.600 to 4.00 μg/g when analysis was performed on piperine derivatives in LPE containing tablets, while the total amount of piperine derivatives in the tablets was quantified at 606 μg/g. Our proposed method is a reliable tool for determining the contents of piperine and the derivatives in LPE and processed foods containing LPE.

Study of the phase composition of fine-grained tungsten carbide based ceramic materials by x-ray phase analysis

The results of X-ray diffraction analysis of qualitative and quantitative phase composition of powder and solid polycrysral samples of the system a-WC/W 2 C are presented. Powder (nanopowder) samples were obtained by plasmochemical synthesis from tungsten oxide and hydrocarbon. High-density fine-grained structure of ceramics was formed by electropulse plasma sintering (spark plasma sintering) of initial industrial a-WC powders (AlfaAesar). Experimental data were obtained on a Shimadzu XRD-7000 X-ray diffractometer (CuKa, λ = 1.54 A). The optimal modes of X-ray shooting of the ceramic samples based on tungsten carbide are presented. In the absence of reference standards for initial crystalline phases (WC and W2C), quantitative phase analysis was carried out using the reference intensity ratio (RIR) or corundum number (instead of the method of calibration curve). The required quantitative ratios were calculated using the structural parameters of corundum a-Al 2 O 3 and phases a-WC, W 2 C. The results of determining the repeatability of the intensity values were used to select the optimal exposure time and width of the receiving slit of the detector of diffracted X-rays. Study of the effect of the quality of sample preparation on the sensitivity of qualitative X-ray phase analysis showed the feasibility of grinding of the surface of solid ceramic samples and their pre-polishing with a diamond paste (grain size not less than 5/3 pm). The accuracy of quantitative phase analysis of powder and sintered ceramic samples was evaluated. The layer-by-layer phase analysis of the ceramic preform revealed a preferential crystallite orientation (texture) in the surface layer and the absence of the impurity phase W 2 C. The sensitivity of X-ray phase analysis to the content of a-W 2 C phase in nanopowders of tungsten monocarbide has been estimated.

Feasibility of Single Post-Contrast Dual-Energy CT for Pediatric Treatment Planning and Dose Calculation

Standard practice requires a separate non-contrast scan for dose calculation, especially for proton therapy, when iodinated contrast is administered during CT simulation. Based on the observation that the presence of iodine strongly affects the Hounsfield unit (HU) more than electron density (ED), we hypothesized that information derived from post-contrast dual-energy CT (DECT) would alone suffice for accurate dose calculation in both photon and proton therapy. Ten pediatric patients with abdominal tumors received DECT scans before and after iodinated contrast administration for treatment planning. In addition to HU images, ED images were generated for direct photon dose calculation and also combined with effective atomic number images to form stopping power ratio (SPR) images for direct proton dose calculation. Dose distributions of DECT-based methods (i.e., direct calculation) were compared to those of conventional calibration curve methods that map HU to ED and SPR. Both 7-field coplanar photon and 2-field posterior oblique SFUD/MFO treatment plans were simulated for each patient using pre- and post-contrast scans. For photon plans, conventional and DECT approaches based on post-contrast scans underestimated PTV D99 by 0.87±0.70% (p=0.18) and 0.36±0.31% (p=0.34), respectively. Iodine concentration in kidneys was weakly associated with the deviation in D99 for the conventional method (R2=0.10) and DECT (R2=0.02). For proton plans, the errors in CTV D99 were 3.67±2.43% (p=0.0001) and 0.30±0.25% (p=0.40) for conventional and DECT approaches, respectively. Changes to the proton beam range were quite noticeable in the conventional approach. Iodine concentration in kidneys was also highly associated with the D99 deviation for the conventional approach (R2=0.83) while no association existed for DECT (R2=0.007). Compared to true non-contrast plans, the presence of iodine contrast on conventional CT resulted in a large dosimetric error for proton therapy, but to a lesser degree for photon therapy. These errors can be greatly reduced if ED and SPR derived from DECT are used instead, which opens the possibility of using only single post-contrast CT for RT simulation and dose calculation with a lesser imaging dose to younger children.Abstract 3670; Table 1Patient #DiagnosisDisease SiteAge (y)Renal Iodine Uptake (mg/ml)Proton PlanningPhoton PlanningCONV CT ΔD99 (%)DECT ΔD99 (%)CONV CT ΔD99 (%)DECT ΔD99 (%)1NeuroblastomaAdrenal (L)132.391.10.11.40.92NeuroblastomaAdrenal (L)62.462.50.10.20.13NeuroblastomaAdrenal (L)53.101.20.40.40.14NeuroblastomaAdrenal (R)43.312.80.20.50.25NeuroblastomaAdrenal (L)63.371.80.81.50.96NeuroblastomaAdrenal (R)43.392.30.20.60.17NeuroblastomaAdrenal (R)114.564.10.70.20.28Hodgkin LymphomaRetroperitoneal L.N.204.746.50.20.40.59Hodgkin LymphomaPorta Hepatis L.N.114.837.30.11.20.310RhabdomyosarcomaPara-Aortic L.N.185.337.10.22.30.3Avg.N/AN/A9.83.753.70.30.90.4 Open table in a new tab

Indirect electrochemical determination of sulfates in mineral water by a flow-through system

The paper describes the indirect determination of sulfates by in-electrode coulometric indication method. The principle of the determination of sulfates consists in the on-line coupling of the exchange column filled with barium chromate and the flow-through coulometric analyser. In the column BaCrO4(s) converts to BaSO4(s) according to the equation: BaCrO4(s)+SO42−(aq)→BaSO4(s)+CrO42−(aq). This conversion is caused by the lower solubility of BaSO4(s) compared to the solubility of BaCrO4(s). Subsequently, the concentration of the chromate in the eluate solution was determined by the in-electrode coulometric indication method in the electrode made of reticulated vitreous carbon. The solution flowing out of the column was mixed in the flow-through analyser with 0.4 mol L−1 hydrochloric acid and the concentration of chromates was determined by direct reduction of Cr(VI) to Cr(III) with a constant current. The determination was evaluated by the calibration curve method. The linear range of the calibration curve was 3.9–100 mg L−1. The detection limit and the accuracy were 1.3 mg L−1 and 3.2%, respectively. The interference of the bicarbonate was eliminated through a conversion to insoluble carbonate by boiling the sample. The procedure was validated by analyses of certified reference material and bottled mineral water samples. A good agreement with the ion chromatography was achieved for all samples.

Screening of multiple pesticide residues in Jinyinhua Formula Granules

To evaluate the pesticide residue risk of Jinyinhua Formula Granules( made from Lonicerae Japonicae Flos) used in the market preliminarily,20 samples of Jinyinhua Formula Granules from 5 manufactures were collected randomly through the national evaluative sampling test program. Totally 262 pesticides( involving 270 chemical monomers) with monitoring significance to traditional Chinese medicinal materials were detected. Samples were extracted by high speed homogenate with acetonitrile as solvent. And their residues were analyzed by GC-MS/MS and LC-MS/MS in MRM mode. No less than 2 groups of characteristic ion pairs were adopted for qualitative detection,and the calibration curve method was used for quantitative detection. The results showed that 20 pesticides were detected in 20 batches of Jinyinhua Formula Granules,with an average of about 9 pesticides detected in every batch,but no restricted pesticide was detected. The detected pesticides were all at the trace level,which was far lower than the limit of the general food standard. Therefore,the safety risk was low in Jinyinhua Formula Granules. In this study,a screening method for pesticide residues in Jinyinhua Formula Granules was established for the first time. The method was accurate and rapid,and the detection indicators were highly targeted. The results could provide theoretical reference for the prevention and control of pesticide safety risks in Jinyinhua Formula Granules and even traditional Chinese medicine formula granules.

KADAR Fe DAN Zn DALAM KRIM KENTAL MANIS KEMASAN KALENG EXPIRE DAN NON EXPIRE MENGGUNAKAN HIDROGEN PEROKSIDA (H2O2) UNTUK DESTRUKSI BASAH SECARA SPEKTROFOTOMETRI SERAPAN ATOM (SSA)

Sweetened condensed milk is generally packaged in a can which is made from iron and zinc. Iron and zinc can have corrosion with the increasing of contact time and changing condition so that they will contaminate the milk. The purpose of this research are to determine the best wet destruction method, find out the effect of adding 30% H2O2 at varied volume in the process of wet destruction, to find out Fe and Zn content in expire and non-expired sweetened condensed milk and to compare the results with the national quality standard. Sample was wet destructed by using variation of 70% HNO3: 30% H2O2 which is 3:0 (method A); 3:0.5 (method B) 3:1 (method C); 3:2 (method D) then the results were measured by using Atomic Absorption Spectrophotometer. Analysis of Fe used standard addition curve method whereas the analysis of Zn used calibration curve method. The results of the analysis showed that the best variation of HNO3:H2O2 in wet destruction method was 3:0.5 for Fe analysis and 3:2 for Zn analysis. The addition of 30% H2O2 at varied volume in wet destruction for Fe analysis gave significantly different results for non-expired sweetened condensed milk but were not significantly different for expired sweetened condensed milk. Whereas, the analysis of Zn gave significantly different results for both non-expired and expired sweetened condensed milk. The metal content in the expired and non-expired sweetened condensed milk which were wet destructed by using the best solvent compotition obtained 0,2759 and 0,7126 mg/kg for Fe and 4,1645 and 2,4367 mg/kg for Zn metal. The Fe and Zn content in the sweetened condensed milk are still below the maximum limit that set by SNI.&#x0D; Keywords: Fe, H2O2, Atomic Absorption Spectrophotometer, sweetened condensed milk, Zn

One-pot fabrication of magnetic fluorinated carbon nanotubes adsorbent for efficient extraction of perfluoroalkyl carboxylic acids and perfluoroalkyl sulfonic acids in environmental water samples

Efficient extraction of perfluoroalkyl carboxylic acids (PFCAs) and perfluoroalkyl sulfonic acids (PFSAs) is challenging due to their highly fluorinated property. Based on the particular characters of PFCAs and PFSAs, a new type of magnetic fluorinated carbon nanotubes adsorbent (MFCA) for magnetic solid phase extraction (MSPE) was fabricated facilely using one-pot hydrothermal approach. The morphology, structure and magnetic properties of the prepared MFCA were investigated by Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy and vibrating sample magnetometry. It was observed that the resultant adsorbent possessed satisfactory superparamagnetism and saturation magnetism. Furthermore, the MFCA exhibited excellent enrichment performance for target PFCAs and PFSAs by means of fluorous-fluorous, hydrophobic and hydrogen bonding interactions. Under the most favorable preparation and extraction conditions, the proposed MFCA/MSPE was combined with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) to quantify ultra trace target analytes in environmental water samples. The limits of detection (S/N = 3) of PFCAs and PFSAs were 0.010–0.036 ng/L and 0.024–0.50 ng/L, respectively. In addition, the introduced approach also displayed other features such as quick extraction procedure, wide linear dynamic ranges, excellent method precision and eco-friendliness. Finally, the concentrations of PFCAs and PFSAs in tap, river, lake and waste water samples were successfully measured by isotope internal standard calibration curve method.

Development Method for Determination of Aspirin as Sodium Salicylate by UV-VIS Spectroscopy

New, easy and quick way to signal U.V. – Vis. spectroscopy was developed and validated for the estimation of Aspirin in pure form, and in respective formulations. The appropriate solubility of the drug and the maximum sensitivity of the assay were found as Salicylate, the peak of maximum absorbance of Salicylate was appear at (535 nm) in the wavelength scope of (300-900 nm); The linear calibration curve of aspirin concentrations range (10-80 ppm) are shown to show the regression equation (Y=0.0086X - 0.0429), and correlation Coefficient (R2 = 0.9999), the LOQ for Aspirin was up to (5.43742 – 0.306928 mg.L−1), while LOD were (1.794348 - 0.101286 mg.L−1).This method has been validated and applied to the estimate of aspirin from various companies in Iraqi marts, no intrusions was found from tablet of aspirin excipients at the favored wavelength and conditions of estimate; Concluded that the method developed was perfect, precise, accurate, and replicable. As well as it can be directly applied to determine Salicylate and indirectly for the estimation of Aspirin content in pharmaceutical formulations, by calibration curve method or standard addition method.

Development and validation of GLC/MS-procedure of doxylamine quantitative determination

Doxylamine is a hypnotic medicine used for treatment of minor sleep disorders and is a frequent cause of poisoning.Aim. To develop GLC/MS-procedure of doxylamine quantification and carry out step-by-step validation ofthe developed procedure in the variants of the method of calibration curve, method of standard and method of additions.Results. The chromatographic conditions have been chosen for doxylamine determination by the method of GLC with mass-spectrometry detection with temperature program changing during the analysis from 70 °C to 320 °C. Retention time for doxylamine is 14.53 min. To prove the possibility of the proposed procedure application in further analysis its validation has been carried out in the variants of the method of calibration curve, method of standard and method of additions. Such validation parameters as in process stability, linearity, accuracy, precision and limit of determination have been estimated by model solutions.Experimental part. Conditions of chromatographic analysis: Agilent 6890N/5973N/7683; НР-5MS ∅0.25 mm × 30 m, 0.25 μm; DB-17MS ∅0.25 mm × 30 m, 0.15 μm; columns are connected sequentially through Deans switch; thermostat – 70 CºС (2 min), 45 ºС/min to 210 ºС, 6 ºС/min to 320 ºС (12.56 min); transfer line – 280 ºС; ion source – 230 ºС; quadrupole – 150 ºС; electron impact, 70eV; 40 – 750 m/z; injector – 250 ºС; splitless mode; inlet carrier gas (helium) pressure: 1st column – 26.06 psi, 2nd column – 19.30 psi.Conclusions. New procedure of doxylamine quantitative determination by the method of GLC/MS has been developed. Its validation has been carried out and acceptability for application has been shown.

Development and validation of HPLC/UV-procedures for quantification of metronidazole in the blood and urine

Metronidazole belongs to the group of antiprotozoal medicines and widely used for the treatment of infectious diseases; the medicine has a number of side effects manifested by usual symptoms of acute intoxication, especially when interacting with other drugs and alcohol.Aim. To apply the system of MiLiChrome® A-02 HPLC-analyzer widely used in the Ukrainian laboratories of forensic toxicology for the metronidazole quantitative determination in biological fluids and carry out validation of the procedures developed.Materials and methods. The sample preparation of blood and urine was carried out by extraction with acetonitrile and 2-propanol followed by separation of the organic layer under the conditions of the aqueous phase saturation with ammonium sulfate. Previously blood and urine were treated with acids. Isolation was carried out in the strong acid, neutral and weak alkaline medium.Results and discussion. To find the optimal conditions of the sample preparation such validation parameters as specificity/selectivity and recovery were determined. The results of the blank samples analysis were acceptable for all variants of the sample preparation procedures. Recovery values were reproducible for all procedures of analysis studied, but efficacy of metronidazole isolation was variable – from 85% to 97 %. The results of verification of metronidazole stability showed the necessity to carry out all measurements within 12 hours after obtaining the solutions to be analyzed. The results of determination of linearity, accuracy and precision were the evidenceof acceptable systematic and random errors of the HPLC/UV-procedures studied in the variant of the method of calibration curve, method of standard and method of additions.Conclusions. The set of HPLC/UV-procedures for the metronidazole quantitative determination in blood and urine has been developed. Validation of the procedures developed has been carried out.

An advanced spectroscopic approach (LIBS in combination with AAS): a steadfast means to probe the elemental composition of monosodium glutamate

The elemental composition of monosodium glutamate (MSG) was probed by engaging a laser-induced breakdown spectroscopy (LIBS) analytical technique. The LIBS spectra of MSG were acquired in air pressure with an appropriate detector (LIBS2000 + , Ocean Optics) with an optical resolution of ~0.06 nm in the spectral range from 220 to 720 nm. Analyses of the acquired LIBS spectra revealed the presence of Ag, Ca, Mg, S and Na in the sample. To maximize the signal to noise ratio in the resulting LIBS spectra, the experimental parameters, such as pulse energy and gate delay, were optimized. The accomplishment of local thermodynamic equilibrium supposition was confirmed by the McWhirter’s criterion and in view of the relaxation time, as well as the diffusion length of the atoms in the plasma. For the determination of relative concentrations of detected elements in MSG, we used three LIBS-based approaches, i.e. by setting the concentration of Na as the calibration, by setting the sum of all concentrations as the calibration and by the calibration curve method. The same sample was also subjected to the more standard analytical tool of atomic absorption spectroscopy, and its results were cross-compared with the findings of LIBS to confirm its validity. It was highly encouraging to find that both results were in sound agreement.

Dose Reconstruction Using Electron Paramagnetic Resonance Dosimetry on Tooth Enamel From Wild Boar Living in the Fukushima Exclusion Zone

The goal of the study was to establish characteristics of Japanese wild boar tooth enamel in the dose region of 0.25-2.0 Gy and to reconstruct external absorbed doses to wild boar native to the Fukushima exclusion zone using electron paramagnetic resonance dosimetry. The significance of Japanese wild boar in their ecosystem and their position within the trophic hierarchy make the wild boar a species of particular importance and therefore, the focus of this study. Dose response linearity and variability of enamel originating from various wild boar were investigated. Radiation dose response of Japanese wild boar tooth enamel in the range of 0.25-2.0 Gy was found to be linear, and the average variation in dose response between teeth originating from the same boar specimen was nearly 30%. No statistically significant difference in dose response was found based on sex of the boar or in permanent molar teeth of boar of differing ages. Electron paramagnetic resonance absorbed doses to boar tooth enamel were successfully reconstructed using the calibration curve method and converted into estimates of absorbed dose to soft tissue with large associated confidence intervals. The critical level dose value for the calibration curve was 1.0 Gy and the detection limit dose was 1.8 Gy, suggesting that this method would be more beneficial for boar with lifetime absorbed doses greater than 1.0 Gy. The method of reconstructing external absorbed doses using electron paramagnetic resonance dosimetry with tooth enamel from Japanese wild boar as dosimeters has proven to be a viable method which can be used to reconstruct absorbed doses to wildlife in accident-stricken areas in the absence of alternative dosimetry.