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Van Echelpoel, R.; Parrilla, M.; Sleegers, N.; Thiruvottriyur Shanmugam, S.; van Nuijs, A.L.N.; Slosse, A.; Van Durme, F.; De Wael, K. |
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Title |
Validated portable device for the qualitative and quantitative electrochemical detection of MDMA ready for on-site use |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
Microchemical journal |
Abbreviated Journal |
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Volume |
190 |
Issue |
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Pages |
108693-10 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Toxicological Centre; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
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Abstract |
Identifying and quantifying 3,4-methylenedioxymethamphetamine (MDMA) on-site in suspected illicit drug samples, whether it be at recreational settings or manufacturing sites, is a major challenge for law enforcement agencies (LEAs). Various analytical techniques exist to fulfil this goal, e.g. colourimetry and portable spectroscopic techniques, each having its specific limitations (e.g. low accuracy, fluorescence, no quantification) and strengths (e.g. fast, easy to use). In this work, for the first time, an electrochemical MDMA sensor is presented to become a detection tool that can realistically be used on-site. More specifically, the use of a single buffer solution and an unmodified screen-printed electrode, along with the integration of a data analysis algorithm and mobile application permits the straightforward on-site identification and quantification of MDMA in suspicious samples. Multiple studies investigating different parameters, including pH, concentration, reproducibility, temperature and binary mixture analyses, were executed. To fully understand all the occurring redox processes, liquid chromatography coupled with high-resolution mass spectrometry analysis of partially electrolyzed MDMA samples was performed unravelling oxidation of the methylenedioxy group. Validation of the methodology was executed on 15 MDMA street samples analysed by gas chromatography coupled with mass spectrometry and compared with the performance of a commercial portable Raman and Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR-FTIR) device. The novel methodology outperformed the spectroscopic techniques, correctly identifying all 15 street samples. Additionally, the electrochemical sensor predicted the purity of the tablets with a mean absolute error of 2.3%. Overall, this new, electrochemical detection strategy provides LEAs the rapid, low-cost, on-site detection and quantification of MDMA in suspicious samples, without requiring specialized training. |
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Wos |
000977060400001 |
Publication Date |
2023-03-31 |
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Edition |
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ISSN |
0026-265x; 0026-265x |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.8 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 4.8; 2023 IF: 3.034 |
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Call Number |
UA @ admin @ c:irua:195415 |
Serial |
8952 |
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Author |
Pastorelli, G.; Miranda, A.S.O.; Avranovich Clerici, E.; d'Imporzano, P.; Hansen, B.V.; Janssens, K.; Davies, G.R.; Borring, N. |
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Title |
Darkening of lead white in old master drawings and historic prints : a multi-analytical investigation |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Microchemical journal |
Abbreviated Journal |
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Volume |
199 |
Issue |
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Pages |
109912-10 |
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Keywords |
A1 Journal article; Antwerp X-ray Imaging and Spectroscopy (AXIS) |
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Abstract |
Old master drawings and historic prints often feature white highlights, which are typically painted using lead white, one of the most widely used historical white pigments. However, it has been observed that many of these highlights discolour over time, becoming dark brown or black due to unclear degradation processes. This phenomenon not only misrepresents the original artefacts, threatening their suitability for public display, but also diminishes their longevity. To ensure their preservation, it is essential to determine why some lead white highlights in these museum objects retain their light tones while others are prone to darkening. The objective of this study was to identify the relationships between the composition, provenance, and production methods of lead white pigments, and their role in the discolouration observed on drawings, lithographs and early photographs. Selected samples and artefacts were examined using a range of analytical techniques, namely X-ray fluorescence spectroscopy (XRF), X-ray powder diffraction (XRPD), and lead isotope analysis. While XRF analyses confirmed the presence of lead as the primary element in the majority of the highlights, XRPD measurements identified a variety of lead compounds such as the carbonates cerussite and hydrocerussite alongside galena-a black crystalline sulfide-and lead sulfates. Additionally, isotope analyses classified the lead raw materials into five main groups. Through these measurements, the examined lead white pigments were categorised based on their compositional properties in relation to the raw materials used, as well as their geographical and temporal origin. A significant finding is that lead white pigments from different production periods, spanning from older to more modern, may be characterised by varying proneness to discolouration irrespective of their provenance. |
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Wos |
001166502200001 |
Publication Date |
2024-01-03 |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0026-265x; 0026-265x |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
4.8 |
Times cited |
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Open Access |
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Notes |
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Most recent IF: 4.8; 2024 IF: 3.034 |
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Call Number |
UA @ admin @ c:irua:205450 |
Serial |
9197 |
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