Sample Preparation Laboratory Research Articles

Spectrophotometric Determination of Norepinephrine in Industrial Equipment Cleaning Rinse Water by Its Own Absorbance and The Tollens’ Reagent

A literature review of the available spectrophotometric methods of determination of catecholamines is presented. Based on this review, two simple spectrophotometric methods for the determination of norepinephrine bitartrate in pharmaceutical formulations and industrial equipment cleaning rinse waters were chosen and validated. The first method for the determination of norepinephrine at ppm levels utilizes the absorbance band of the solution of norepinephrine bitartrate at 279 nm. The second method for the determination of norepinephrine at ppb levels is based on the reaction of norepinephrine with the Tollens’ reagent in the presence of the cationic surfactant cetylpyridinium chloride and the colorimetric determination of the formed colloidal silver nanoparticles. The calibration graphs are linear in the range from 1 to 150 mg/l of norepinephrine for the first method and 25 µg/l to 10 mg/l for the second method. The molar attenuation coefficients are 388 and 7560 m2/mol, respectively, the limits of detection are 1.1 mg/l and 3.1 µg/l, and the limits of quantification are 3.3 mg/l and 9.4 µg/l, respectively. Both methods are selective concerning the common excipients, show good accuracy (the relative uncertainties do not exceed 4 and 7%, respectively) and precision (the relative standard deviations do not exceed 4 and 7%, respectively), and do not require lengthy sample preparation and sophisticated laboratory equipment.

Spectrophotometric determination of L-α-glycerylphosphorylcholine in pharmaceutical formulations and industrial equipment cleaning rinse water with the WAKO Phospholipids C assay kit

A simple spectrophotometric method for the determination of L-α-glycerylphosphorylcholine in pharmaceutical formulations and industrial equipment cleaning rinse water using the enzyme glycerophosphocholine phosphodiesterase and the WAKO Phospholipids C assay kit was proposed. The method is based on the enzymatic hydrolysis of α-GPC to choline by glycerophosphocholine phosphodiesterase, the reaction of choline with the components of the assay kit, and the colourimetric determination of the formed product. The calibration graph is linear in the range from 1 to 40 mg/l of α-GPC, the molar attenuation coefficient is 1,110 m2/mol, the limit of detection is 1 mg/l, the limit of quantification is 3.3 mg/l, the method is selective with respect to the common excipients, shows a good accuracy (the relative uncertainty does not exceed 7%) and precision (the relative standard deviation does not exceed 5.5%), does not require lengthy sample preparation and sophisticated laboratory equipment and is suitable for the routine analysis of pharmaceutical formulations and industrial equipment cleaning rinse water.

UV-Spectrophotometric Determination of the Active Pharmaceutical Ingredients Meloxicam and Nimesulide in Cleaning Validation Samples with Sodium Carbonate

The spectrophotometric methods of determination of the active pharmaceutical ingredients meloxicam and nimesulide were reviewed and a simple UV-spectrophotometric method for the determination of these active pharmaceutical ingredients in industrial equipment cleaning validation samples was proposed. The methods were based on extraction of the residual quantities of meloxicam and nimesulide from the manufacturing equipment surface by the concentrated sodium carbonate solution and the subsequent UV-spectrophotometric determination of the basic forms of the drugs at the wavelength of 362 nm for meloxicam and at 397 nm for nimesulide. The calibration graphs were linear in the range from 5 to 25 mg/L of both nimesulide and meloxicam, the molar attenuation coefficients were 6100 m2/mol for nimesulide and 9100 m2/mol for meloxicam, the limit of detection was 0.8 mg/L for nimesulide and 1.9 mg/L for meloxicam and the limit of quantification was 2.5 mg/L for nimesulide and 5.8 mg/L for meloxicam. The methods were selective with respect to the common excipients, showed a good accuracy (the relative uncertainty did not exceed 7%) and precision (the relative standard deviation did not exceed 4%), did not require lengthy sample preparation or sophisticated laboratory equipment and were suitable for the routine analysis of cleaning validation samples.

Cosmogenic 10Be and 26Al sample preparation at the University of Wollongong

The University of Wollongong (UOW) cosmogenic 10Be and 26Al sample preparation laboratory has been in operation since the start of 2017. As primarily a feeder laboratory to ANSTO’s Centre for Accelerator Science, our sample preparation procedures have been optimised with consideration to the setup of ANSTO’s 6MV SIRIUS accelerator, and aim to achieve a balance between sample throughput as well as Be and Al target purity. A comparatively small number of samples (n = 68) have also been prepared for measurement at the Australian National University 14UD accelerator. 10Be/9Be ratios of procedural blanks measured on SIRIUS have fluctuated over time with the median for the year 2017 being 5.16 × 10−16 (IQR = 4.11 × 10−16 to 7.16 × 10−16, n = 18), increasing to 1.62 × 10−15 (IQR = 1.05 × 10−15 to 2.17 × 10−15, n = 31) for 2018 and 2019, a period coinciding with elevated boron levels in our samples, and finally decreasing to 1.15 × 10−15 (IQR = 8.63 × 10−16 to 1.60 × 10−15, n = 34) for 2020 and 2021. In contrast, 26Al/27Al ratios of procedural blanks measured on SIRIUS have shown a slight but continuous improvement over time with the median for 2017 of 1.70 × 10−15 (IQR = 8.19 × 10−16 to 5.25 × 10−15, n = 12) decreasing to 1.07 × 10−15 (IQR = 8.5 × 10−16 to 1.53 × 10−15, n = 13) for 2021. Median 10Be/9Be relative uncertainty of procedural blanks analysed on SIRIUS is 18 % (IQR = 15 % to 22 %; n = 86) whereas the median 26Al/27Al relative uncertainty of procedural blanks is higher at 60 % (IQR = 41 % to 100 %; n = 56), statistic resulting from most blanks yielding low 26Al counts (median = 2; IQR = 1–4.5). Average 9BeO− output relative to standard is between ∼ 70 % – 80 % for samples analysed on SIRIUS (n = 895) and ∼ 130 % for samples analysed at ANU (n = 68). 27Al− output relative to standard is lower for samples pressed into cathodes at UOW (∼60 %, n = 432) and analysed on SIRIUS than for those pressed at ANSTO (∼90 %, n = 119). Average 27Al− output relative to standard for samples analysed at ANU is ∼ 80 % (n = 62). 10Be and 26Al measurements of various laboratory intercomparison materials prepared at UOW between 2017 and 2022 yield results in agreement with consensus values confirming that our chemistry procedures are robust and in line with those elsewhere.

Spectrophotometric determination of bismuth potassium ammonium citrate in cleaning wastes of industrial equipment with 4-(2’-pyridylazo)-resorcinol

A simple spectrophotometric method for the determination of bismuth potassium ammonium citrate in the cleaning wastes of industrial equipment using 4-(2’-pyridylazo)-resorcinol is proposed. The method is based on displacement of bismuth from its potassium ammonium citrate by 4-(2’-pyridylazo)-resorcinol, formation of the colored complex, and the colorimetric determination of the resulting product. The calibration curve is linear within the range from 4 to 20 mg/L of bismuth potassium ammonium citrate, the molar attenuation coefficient is 10,100 m2/mol, the detection limit is 2.7 mg/L, the quantification limit is 8.2 mg/L. The method is selective with respect to the common excipients, exhibits a good accuracy (the relative uncertainty does not exceed 10%) and precision (the relative standard deviation does not exceed 5%), does not require lengthy sample preparation and sophisticated laboratory equipment and is suitable for the routine analysis of the cleaning wastes of industrial equipment.

Using Real Interpretative Differences to Assess Inter-laboratory Isotopic Variability Due to Sample Preparation

Here we present a two-part study to assess isotope data comparability between two sample preparation laboratories, based on the concept of Real Interpretative Differences (RID). Inter-laboratory isotopic variability should be evaluated prior to compiling data from different sources. Isotopic variability can result from two main causes: sample preparation and sample analysis. We compared the carbon and nitrogen isotope delta (δ) values of 20 modern human bone collagen sample pairs—representing seven individuals from diverse backgrounds—thatwere prepared close in time at two laboratories and then analyzed at one facility. From this study, values for RID of preparation, or RIDprep, were calculated for bone collagen as 0.43‰ and 0.75‰ for δ13C values and δ15N values, respectively. These RIDprep values were tested using a set of 30 bone collagen sample pairs—representing 30 modern individuals—that were first prepared over a span of five years (2014–2019) at one laboratory; they were prepared again at the second laboratory in 2019. While the differences in isotope δ values between the paired samples in the second study were statistically significant, they did not exceed the calculated RIDprep values for either carbon (30 comparisons) or nitrogen (30 comparisons)—with the exception of one carbon difference in a single paired bone sample. The inherent error rate in combining the isotope test results was thus calculated as 1.7%. This study demonstrated that the isotope data generated from human bone collagen prepared at one laboratory can be reliably compared to data generated from samples prepared at the other laboratory.

Evaluating of IAQ-Index and TVOC Parameter-Based Sensors for Hazardous Gases Detection and Alarming Systems.

The measurement of air quality parameters for indoor environments is of increasing importance to provide sufficient safety conditions for workers, especially in places including dangerous chemicals and materials such as laboratories, factories, and industrial locations. Indoor air quality index (IAQ-index) and total volatile organic Compounds (TVOC) are two important parameters to measure air impurities or air pollution. Both parameters are widely used in gases sensing applications. In this paper, the IAQ-index and TVOCs have been investigated to identify the best and most flexible solution for air quality threshold selection of hazardous/toxic gases detection and alarming systems. The TVOCs from the SGP30 gas sensor and the IAQ-index from the SGP40 gas sensor were tested with 12 different organic solvents. The two gas sensors are combined with an IoT-based microcontroller for data acquisition and data transfer to an IoT-cloud for further processing, storing, and monitoring purposes. Extensive tests of both sensors were carried out to determine the minimum detectable volume depending on the distance between the sensor node and the leakage source. The test scenarios included static tests in a classical chemical hood, as well as tests with a mobile robot in an automated sample preparation laboratory with different positions.

A new national 1 MV AMS laboratory at TÜBİTAK MRC in Turkey

A 1 MV accelerator mass spectrometer (AMS) dedicated to measuring 14C as well as capabilities to measure 10Be, 26Al, 129I, 41Ca was installed at TÜBİTAK, Marmara Research Center, Earth and Marine Science Institute (MRC-EMSI) in Turkey. Also, a sample preparation laboratory with automatic and manual graphitization systems for radiocarbon dating was established. Standards SRM 4990C (Ox-II), IAEA-C7, and IAEA-C8 were used to conduct the acceptance tests. Graphite powder, phthalic anhydride and IAEA-C1 were used to measure the background level. Acceptance test results validated radiocarbon dating accuracy proficiencies for 14C/12C and background levels. After site acceptance tests are completed, the laboratory with AMS and graphitization systems were operated to analyze archaeology, earth, and environmental research study samples from national research groups. The laboratory focuses on developing interdisciplinary projects that demand 14C, 10Be, 26Al, 41Ca and 129I analysis. Furthermore, the laboratory is accepting samples for test and analysis services. All radiocarbon measurements are carried out with standard reference materials SRM 4990C (Ox-II), IAEA-C7, IAEA-C8 as well as processed and unprocessed blank are measured routinely to monitor measurement quality.

RADIOCARBON IN MEXICO: FROM PROPORTIONAL COUNTERS TO AMS

ABSTRACTAugusto Moreno is credited with establishing the first radiocarbon (14C) laboratory in Mexico in the 1950s, however, 14C measurement with the accelerator mass spectrometry (AMS) technique was not achieved in our country until 2003. Douglas Donahue from the University of Arizona, a pioneer in using AMS for 14C dating, participated in that experiment; then, the idea of establishing a 14C AMS laboratory evolved into a feasible project. This was finally reached in 2013, thanks to the technological developments in AMS and sample preparation with automated equipment, and the backing and support of the National Autonomous University of Mexico and the National Council for Science and Technology. The Mexican AMS Laboratory, LEMA, with a compact 1 MV system from High Voltage Engineering Europa, and its sample preparation laboratories with IonPlus automated graphitization equipment, is now a reality.

Development of cosmogenic nuclide capabilities in South Africa and applications in Southern African geomorphology

ABSTRACT Cosmogenic nuclide (CN) applications offer methods to quantify rates of landscape change and of dating geomorphological deposits and surfaces. Over the past two decades, CNs have been used to determine denudation rates, constrain uplift rates and determine burial ages of sediments in different geomorphological settings across the Southern African landscape. Here, we first give an overview of the landscape evolution of Southern Africa and how CN-based studies have contributed to this subject. Then we give a compilation of CN denudation data from Southern Africa, which show that average erosion rates have decreased by an order of magnitude since the late Cenozoic. Finally, we present the state of CN infrastructure and capabilities in South Africa as well as envisaged future developments. An Accelerator Mass Spectrometer (AMS) has become operational for carbon-14, beryllium-10 and aluminium-26 measurements at the National Research Foundation (NRF) iThemba Laboratory for Accelerator Based Sciences (LABS) in Gauteng since 2017. The measurements’ accuracy and precision compare well with other AMS laboratories internationally. Local sample preparation laboratories are currently available with limited capabilities and are mostly still under development.

ES11.06 Toxicology of Tobacco and Metabolites, and Impact on Cancer

ES11.06 Toxicology of Tobacco and Metabolites, and Impact on Cancer

Radiocarbon Sample Preparation Procedures and the First Status Report from the Bristol Radiocarbon AMS (BRAMS) Facility

ABSTRACTThe Bristol Radiocarbon Accelerator Mass Spectrometry (BRAMS) Facility was established at the University of Bristol after the commissioning of our dedicated sample preparation laboratories and the installation and acceptance of the BrisMICADAS AMS in 2016. Routine measurements commenced in mid-2016, once validation was completed for each sample type. Herein, we give an overview of the standard pretreatment methods currently employed in the Facility and the results of radiocarbon (14C) determinations on a wide range of standards, blank materials, and intercomparison samples which have been measured during our extensive pretreatment method validation program and during our routine 14C analyses.

Calibrate Variations in Biomarker Measures for Improving Prediction with Time-to-event Outcomes.

Novel biologic markers have been used to predict clinical outcomes of many diseases. One specific feature of biomarkers is that they often are measured with variations due to factors such as sample preparation and specific laboratory process. Statistical methods have been proposed to characterize the effects of underlying error-free quantity in association with an outcome, yet the impact of measurement errors in terms of prediction has not been well studied. We focus in this manuscript on using biomarkers for predicting an individual's future risk for survival outcome. In the setting where replicates of error-prone biomarkers are available in a 'training' population and risk projection is applied to individuals in a 'prediction' population, we propose two-step measurement-error-corrected estimators of absolute risks. We conducted numerical studies to evaluate the predictive performance of the proposed and routine approaches under various assumptions about the measurement error distributions to pinpoint situations when correction of measurement errors might be necessary. We studied the asymptotic properties of the proposed estimators. We applied the estimators to a liver cancer biomarker study to predict risk of liver cancer incidence using age and a novel biomarker, α-Fetoprotein.

Status Report on the Sample Preparation Laboratory for Radiocarbon Dating at the New Bucharest Roams Center

ABSTRACTThe accelerator mass spectrometry (AMS) center at Horia Hulubei National Institute for R&D in Physics and Nuclear Engineering, Bucharest, is based on the latest-generation 1 MV Tandetron® accelerator, produced by High Voltage Engineering Europa (HVEE), The Netherlands. The AMS center became fully functional at the start of 2013, and at the end of 2015 the laboratory established the RoAMS international code and it was added to the list of AMS laboratories maintained by Radiocarbon journal. An important aspect in the establishment of a new AMS laboratory is the declaration and documentation of the adopted protocols and to demonstrate the reliability and reproducibility of the measurements in comparison to internationally recognized reference materials. In this paper, we present the dating results on the Sixth International Radiocarbon Intercomparison (SIRI) samples that were pretreated, graphitized, and measured in our laboratory. The newly developed sample preparation laboratory can handle sample materials as (1) organic materials, (2) wood, (3) bones, and (4) carbonates. The results of our measurements are in very good agreement with the SIRI consensus values and confirm the reliability of our sample preparation laboratory and also the good performance of the HVEE AMS system. The blank levels for the SIRI materials are 0.277±0.045/0.333±0.046 percent modern carbon (pMC) for wood samples, 0.441±0.038 pMC for bone collagen, and 0.239±0.030 pMC for carbonate materials, considering an average mass of 1 mg sample graphite.

AMS and upcoming geochronology facility at Inter University Accelerator Centre (IUAC), New Delhi, India

Inter University Accelerator Centre, an ion accelerator centre, is in the process of setting up a national facility for geochronology. It will be a unique and first such facility in the country to provide the latest and exclusive instrumentation for the geochronological related studies to earth scientists of the country. Within this program various instruments are being installed and a 500 kV Pelletron Accelerator for Accelerator Mass Spectrometry (AMS) has already been set up to measure 14C, 10Be and 26Al radionuclides. A sample preparation laboratory having three automated graphitization equipment and one carbonate handling system has also been set up. Other analytical facilities required for geochronological studies have also been established. This paper provides a brief description of new AMS system, graphitization laboratory for sample preparation, routine 14C measurements, 10Be and 26Al measurements and other instruments installed and planned within the geochronology facility at IUAC.

Rapid, simultaneous and non-destructive assessment of the moisture, water activity, firmness and SO2 content of the intact sulphured-dried apricots using FT-NIRS and chemometrics

The potential of using FT-NIR spectroscopy for the rapid and non-destructive measurement of the moisture, water activity, firmness and SO2 content of the intact sulphured-dried apricots (SDA) was investigated for the first time in the literature. The partial least squares regression (PLS-R) models constructed using FT-NIR spectra were very successful in predicting the moisture content (R2p = 0.986, RMSEP = 1.22%, RPD = 9.15) and water activity (R2p = 0.987, RMSEP = 0.016, RPD = 9.37) of SDAs. Satisfactory results were also obtained for the models developed for the prediction of the firmness (R2p = 0.845, RMSEP = 0.445, RPD = 2.55) and SO2 content (R2p = 0.804, RMSEP = 349 mg kg−1, RPD = 2.27). These results clearly demonstrate that the major quality parameters of SDA can be simultaneously measured in a short time by FT-NIR spectroscopy without any need for the sample preparation or skilled laboratory personnel.

In vitro assessment of sex steroids and related compounds in water and sediments - a critical review.

Detection of endocrine disrupting compounds in water and sediment samples has gained much importance since the evidence of their effects was reported in aquatic ecosystems in the 1990s. The aim of this review is to highlight the advances made in the field of in vitro analysis for the detection of hormonally active compounds with estrogenic, androgenic and progestogenic effects in water and sediment samples. In vitro assays have been developed from yeast, mammalian and in a few cases from fish cells. These assays are based either on the hormone-mediated proliferation of sensitive cell lines or on the hormone-mediated expression of reporter genes. In vitro assays in combination with various sample enrichment methods have been used with limits of detection as low as 0.0027 ng L-1 in water, and 0.0026 ng g-1 in sediments for estrogenicity, 0.1 ng L-1 in water, and 0.5 ng g-1 in sediments for androgenicity, and 5 ng L-1 in water for progestogenicity expressed as equivalent concentrations of standard reference compounds of 17β-estradiol, dihydrotestosterone and progesterone, respectively. The experimental results and limits of quantification, however, are influenced by the methods of sample collection, preparation, and individual laboratory practices.

Sampling of the mineralised tailings dumps – case study of the Mount Morgan project, central Queensland, Australia

ABSTRACTA new sampling protocol was developed to overcome the difficulties in sampling viscous unconsolidated mine tailings. This new procedure involved collection of the entire drill sample from the drill rig cyclone, (approximately 15 kg) which is delivered to the sample preparation laboratory where it was dried, crushed and subsampled. Comminution and subsampling parameters were deduced by estimating the fundamental sampling error and construction of the sampling nomogram. Based on this analysis, the optimal protocol was designed as follows:Drying the entire 15 kg sample at 60°CReporting of sample mass and free moisture contentCrushing of entire sample to 90% passing − 2 mmUse of a rotary sample splitter to collect a 3 kg subsamplePulverising the entire 3 kg subsample to 74 µmCollecting of a 50 g aliquot for fire gold assay with atomic-absorption finishThe quality of sampling was rigorously monitored using sample duplicates, blanks and standards, which have confirmed the accuracy and repeatability of the data. Correlation between field duplicates and original samples was high at 98% with a precision error of 19.8%, which is considered excellent for gold mineralisation. The high quality of the data was important for the accurate evaluation of the project, and enabled the confidence in classifying a significant part of the mineralised endowment as an indicated resource.

Acceptance Tests for AMS Radiocarbon Measurements at iThemba LABS, Gauteng, South Africa

The accelerator mass spectrometer was commissioned recently at the iThemba LABS 6 MV tandem accelerator. Improvements in the vacuum system, requiring procurement of cryo-pumps and the reducing the tank pressure of the N2 + CO2 insulation gas mixture below the level used for IBA measurements, were necessary. This resulted in the reduction of the nitrogen background and improved the resolution of 14C from 14N background in the ionisation chamber. The nitrogen was leaking to the stripping canal because of inadequate sealing. The analysing magnet was scaled to detect C3+ ions, at 3 MV terminal potential. The first sensible spectra allowed for the pin-pointing of many persistent issues. This resulted in measurements with a precision better than 1 pMC, and current blank levels correspond to 12 half-lives of 14C or ∼68000 years. The radiocarbon sample preparation laboratory has reached production status. A brief outlook of the work towards the implementation of the measurement and chemical preparation protocols for radionuclides 10Be and 26Al is also summarised in the conclusion

First Status Report on Radiocarbon Sample Preparation Techniques at the A.E. Lalonde AMS Laboratory (Ottawa, Canada)

AbstractThe A.E. Lalonde accelerator mass spectrometer (3MV, HVEE) was commissioned in early 2014 at the University of Ottawa (Canada). The radiocarbon sample preparation laboratory spent the better part of 2014 undertaking a quality control program, establishing pretreatment protocols, and streamlining sample processing. In the fall of 2014, the first unknown samples were accepted and in the first year of operation well over 1000 targets (~60% unknowns) were analyzed. Here, we present an overview of sample processing protocols and results from routinely measured standards, reference, and blank materials.