TY - JOUR A1 - Knoche, Lisa A1 - Lisec, Jan A1 - Koch, Matthias T1 - Analysis of electrochemical and liver microsomal transformation products of lasalocid by LC/HRMS N2 - Rationale: Lasalocid (LAS), an ionophore, is used in cattle and poultry farming as feed additive for its antibiotic and growth-promoting properties. Literature on transformation products (TP) resulting from LAS degradation is limited. So far, only hydroxylation is found to occur as the metabolic reaction during the LAS degradation. To investigate potential TPs of LAS, we used electrochemistry (EC) and liver microsome (LM) assays to synthesize TPs, which were identified using liquid chromatography high-resolution mass spectrometry (LC/HRMS). Methods: Electrochemically produced TPs were analyzed online by direct coupling of the electrochemical cell to the electrospray ionization (ESI) source of a Sciex Triple-TOF high resolution mass spectrometer. Then, EC-treated LAS solution was collected and analyzed offline using LC/HRMS to confirm stable TPs and improve their annotation with a chemical structure due to informative MS/MS spectra. In a complementary approach, TPs formed by rat and human microsomal incubation were investigated using LC/HRMS. The resulting data were used to investigate LAS modification reactions and elucidate the chemical structure of obtained TPs. Results: The online measurements identified a broad variety of TPs, resulting from modification reactions like (de-)hydrogenation, hydration, methylation, oxidation as well as adduct formation with methanol. We consistently observed different ion complexations of LAS and LAS-TPs (Na+; 2Na+ K+; NaNH4 +; KNH4 +). Two stable methylated EC-TPs were found, structurally annotated, and assigned to a likely modification reaction. Using LM incubation, seven TPs were formed, mostly by oxidation/hydroxylation. After the identification of LM-TPs as Na+-complexes, we identified LM-TPs as K+-complexes. Conclusion: We identified and characterized TPs of LAS using EC- and LM-based methods. Moreover, we found different ion complexes of LAS-based TPs. This knowledge, especially the different ion complexes, may help elucidate the metabolic and environmental degradation pathways of LAS. KW - Mass Spectrometry KW - Electrochemistry KW - ECR KW - Lasalocid KW - Ionophore KW - Transformation products PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-553919 DO - https://doi.org/10.1002/rcm.9349 VL - 36 IS - 18 SP - 1 EP - 10 PB - Wiley online library AN - OPUS4-55391 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Riedel, Soraya A1 - Hülagü, Deniz A1 - Bennet, Francesca A1 - Carl, Peter A1 - Flemig, Sabine A1 - Schmid, Thomas A1 - Schenk, J. A. A1 - Hodoroaba, Vasile-Dan A1 - Schneider, Rudolf T1 - Electrochemical Immunomagnetic Ochratoxin A Sensing: Steps Forward in the Application of 3,3’,5,5’- Tetramethylbenzidine in Amperometric Assays N2 - Electrochemical methods offer great promise in meeting the demand for user-friendly on-site devices for Monitoring important parameters. The food industry often runs own lab procedures, for example, for mycotoxin analysis, but it is a major goal to simplify analysis, linking analytical methods with smart technologies. Enzyme-linked immunosorbent assays, with photometric detection of 3,3’,5,5’-tetramethylbenzidine (TMB),form a good basis for sensitive detection. To provide a straightforward approach for the miniaturization of the detectionstep, we have studied the pitfalls of the electrochemical TMB detection. By cyclic voltammetry it was found that the TMB electrochemistry is strongly dependent on the pH and the electrode material. A stable electrode response to TMB could be achieved at pH 1 on gold electrodes. We created a smartphonebased, electrochemical, immunomagnetic assay for the detection of ochratoxin A in real samples, providing a solid basis forsensing of further analytes. KW - Ochratoxin A KW - Amperometry KW - Cyclic voltammetry KW - Electrochemistry KW - Immunoassay PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-530421 DO - https://doi.org/10.1002/celc.202100446 N1 - Geburtsname von Riedel, Soraya: Höfs, S. - Birth name of Riedel, Soraya: Höfs, S. VL - 8 IS - 13 SP - 2597 EP - 2606 AN - OPUS4-53042 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Konthur, Zoltán T1 - Enzyme-Based Electrochemical Detection of Fumonisins Applying Amperometric Sensing N2 - Fumonisins represent a class of toxic secondary metabolites produced primarily by Fusarium species, notably F. verticillioides and F. proliferatum, though Aspergillus niger can also produce these mycotoxins. They are most commonly found contaminating maize, but other grains are also at risk. Dietary exposure to fumonisins poses serious health risks to both humans and livestock, prompting the European Commission to set regulatory limits on their presence in food and animal feed. Traditional detection methods, such as chromatography, are often costly, are laboratory based and require specialized expertise. To address the need for simpler, more accessible detection methods, portable electrochemical biosensors present a promising solution. In this study, we introduce a novel enzymatic approach for fumonisin detection using amperometric sensing. Here, a recently discovered fumonisin amine oxidase (AnFAO) from Aspergillus niger, which catalyses the oxidative deamination of fumonisins and generates hydrogen peroxide, was produced recombinantly in Escherichia coli. In our hands, the enzyme exhibited higher specific activity toward Fumonisin B1 compared to Fumonisin B2 at the same substrate concentration (0.0037 U/mg and 0.0014 U/mg at 25 µM substrate, respectively). We demonstrated that enzyme activity correlates with both enzyme and substrate concentrations. To detect Fumonisin B1, the enzyme was covalently attached to magnetic particles, and hydrogen peroxide production was measured amperometrically in a flow injection system with Prussian blue carbon electrodes. This method enabled the quantification of Fumonisin B1 concentrations as low as 1.5 µM and proved that recombinant AnFAO effectively deaminated fumonisins even in its immobilized form. These results highlight AnFAO’s potential for developing an enzyme-based electrochemical biosensor to detect fumonisin contamination in food and feed products. T2 - ANAKON 2025 CY - Leipzig, Germany DA - 10.03.2025 KW - Immunoassay KW - Mycotoxin KW - Electrochemistry KW - Antibody KW - Biosensor PY - 2025 AN - OPUS4-63496 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Scholl, Juliane T1 - Fluorinated Additives used in LiBs: Forever Chemicals of Tomorrow? N2 - Fluorinated organic compounds (FOCs) are a type of man-made chemicals characterized by their robust carbon-fluorine bonds, which contribute to their chemical stability and resistance to degradation. This durability makes them valuable in various applications, such as lithium-ion batteries (LiBs) [1-3], could have a significant impact on the environment, but this potential has not yet been fully considered. This study examines the environmental impact of two fluorinated aromatics, tris(pentafluorophenyl)borane (TPFPB) and tris(pentafluorophenyl)phosphine (TPFPP), given their role in enhancing the performance of LiBs[4, 5]. In order to achieve this, a number of laboratory simulation methods were employed, including total oxidizable precursor assay, electrochemistry (EC), Fenton reaction, UV-C irradiation, and hydrolysis. Liquid chromatography and gas chromatography coupled with high-resolution mass spectrometry were employed for the identification of transformation products (TPs) and the prediction of their molecular formulae. Notwithstanding their structural similarities, TPFPB and TPFPP exhibited distinct differences in their electrochemical behavior and degradation pathways. TPFPB was readily transformed via hydroxylation and hydrolysis, resulting in a diverse range of 49 TPs. In total, 28 TPs were newly identified, including oligomers and highly toxic dioxins. In contrast, TPFPP degraded only under extreme conditions, highlighting the need to develop new conditioning protocols for EC. Overall, the simulation experiments produced 9 structurally unique compounds, including 7 previously unidentified partially defluorinated byproducts. This study emphasizes the potential hazards linked to the use of FOCs in lithium-ion batteries and enhances our understanding of the complex environmental interactions of these compounds. T2 - Adlershofer Forschungsforum 2024 CY - Berlin, Germany DA - 11.11.2024 KW - PFAS KW - Lithium-ion batteries KW - Fluorinated Compounds KW - Simulation methods KW - Liquid chromatography/ QTOF-MS KW - Gas chromatography/ QTOF-MS KW - Electrochemistry KW - Photochemistry KW - Top-Assay PY - 2024 AN - OPUS4-61681 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Scholl, Juliane T1 - Forever Chemicals of Tomorrow? Fate of Fluorinated Li-Ion Battery Additives N2 - Fluorinated organic compounds (FOCs) are a category of anthropogenic chemicals distinguished by their resilient carbon-fluorine bonds, which confer significant chemical stability and resistance to degradation. This durability makes them valuable in various applications, particularly in lithium-ion batteries (LiBs) [1,2]. However, the environmental implications of these compounds have not been thoroughly investigated. This study focuses on the environmental impact of two fluorinated aromatic compounds: tris(pentafluorophenyl)borane (TPFPB) and tris(pentafluorophenyl)phosphine (TPFPP), specifically regarding their roles in enhancing LiB performance [3,4]. To assess their environmental fate, we employed a range of laboratory simulation techniques generating transformation products (TPs), including total oxidizable precursor assays, electrochemistry (EC), Fenton reactions, UV-C irradiation, and hydrolysis. We utilized liquid chromatography and gas chromatography coupled with high-resolution mass spectrometry to identify TPs and predict their molecular formulas. Despite their structural similarities, TPFPB and TPFPP displayed differences in electrochemical behavior and degradation pathways. TPFPB underwent significant transformation through hydroxylation and hydrolysis, yielding a diverse array of 49 TPs, including 28 newly identified compounds, including oligomers and minor levels of highly toxic dioxins. In contrast, TPFPP underwent degradation only at extreme conditions, highlighting the necessity for new conditioning protocols in electrochemistry. Overall, our simulation experiments revealed 9 structurally unique compounds, including 7 previously unidentified partially defluorinated byproducts. This study underscores the potential environmental hazards associated with the use of FOCs in lithium-ion batteries and enhances our understanding of the complex interactions these compounds have with the environment. T2 - ANAKON 2025 CY - Leipzig, Germany DA - 10.03.2025 KW - High Resolution Mass Spectrometry (HRMS) KW - Lithium-Ion Batteries KW - Simulation methods KW - PFAS KW - Electrochemistry KW - Photochemistry KW - TOP assay PY - 2025 AN - OPUS4-62805 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Morcillo, Dalia T1 - High-resolution optical isotopic spectrometry as a tool for aging studies of Li-ion batteries N2 - Current activities on Department Analytical Chemistry, Reference Materials about optical isotopic spectrometry as a tool for aging studies of Li-ion batteries. T2 - Adlershofer Kolloquium - FB 1.6 CY - Online meeting DA - 18.05.2021 KW - High-resolution KW - Battery aging KW - Storage Technologies KW - Optical isotopic spectrometry KW - Lithium-ion batteries KW - Inorganic Reference Materials KW - Pouch cell KW - Anode KW - Cathode KW - Electrochemistry KW - Isotope PY - 2021 AN - OPUS4-53712 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Temgoua, Ranil C. T. T1 - Hyphenated Electrochemistry-Liquid Chromatography-Mass Spectrometry (EC-LC-MS) N2 - The coupling of electrochemistry with mass spectrometry (EC-MS) represents a revolutionary approach for studying redox-active compounds, which constitute over 90% of known chemical entities. This poster demonstrates the versatility of EC-MS as a rapid and environmentally friendly alternative to traditional in-vivo and in-vitro methods. Our focus encompasses three key applications: Simulation of drug metabolism pathways, investigation of environmental xenobiotic degradation/fate (eFate), and green synthesis of analytical standards. T2 - 56th annual conference of the DGMS (Deutschen Gesellschaft für Massenspektrometrie) CY - Göttingen, Germany DA - 04.03.2025 KW - Electrochemistry KW - Mass Spectrometry KW - Emerging pollutants KW - Transformation products PY - 2025 AN - OPUS4-63517 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Scholl, Juliane A1 - Lisec, Jan A1 - Haase, Hajo A1 - Koch, Matthias T1 - Identification of transformation products from fluorinated lithium-ion battery additives TPFPB and TPFPP: forever chemicals of tomorrow? N2 - AbstractFluorinated organic compounds (FOCs) represent a class of synthetic chemicals distinguished by their resilient carbon–fluorine bonds, which demonstrate an ability to withstand environmental degradation over an extended period. The integration of FOCs into cutting-edge applications, including lithium-ion batteries (LiBs), presents considerable potential for environmental harm that has not yet been sufficiently addressed. This study focuses on the environmental fate of two fluorinated aromatics, tris(pentafluorophenyl)borane (TPFPB) and tris(pentafluorophenyl)phosphine (TPFPP), given their important role in improving the performance of LiBs. To achieve this, laboratory simulation methods including total oxidizable precursor assay, electrochemistry (EC), Fenton reaction, UV-C irradiation, and hydrolysis were employed. Liquid chromatography and gas chromatography coupled with high-resolution mass spectrometry were used for identification of transformation products (TPs) and prediction of their molecular formulae. Despite the structural similarity between TPFPB and TPFPP, distinct differences in electrochemical behavior and degradation pathways were observed. TPFPB readily underwent hydroxylation and hydrolysis, resulting in a wide range of 49 TPs. A total of 28 TPs were newly identified, including oligomers and highly toxic dioxins. In contrast, TPFPP degraded exclusively under harsh conditions, requiring the development of innovative conditioning protocols for EC. In total, the simulation experiments yielded nine structurally different compounds, including seven previously undescribed, partially defluorinated TPs. This study highlights the potential risks associated with the use of FOCs in LiBs and provides insight into the complex environmental behavior of FOCs. KW - Mass Spectrometry KW - LiBs KW - POPs KW - Transformation products KW - Electrochemistry PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-611339 DO - https://doi.org/10.1007/s00216-024-05526-z SP - 1 EP - 15 PB - Springer Science and Business Media LLC AN - OPUS4-61133 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Riedel, Soraya T1 - Immunomagnetic ochratoxin a assay with electrochemical 3,3′,5,5′ tetramethylbenzidine detection N2 - The demand for miniaturized analytical devices monitoring important parameters in the food and medical industry has increased strongly in the past decades. With fast progress, smart technologies are finding their way into our everyday life. For the future, it is, therefore, a major goal to also link analytical methods with smart technologies to create user-friendly on-site devices. In food industry the monitoring of harmful substances such as dioxins, heavy metals or mycotoxins plays a key role, since the European Commission prescribes legal limits for various food products and beverages[1]. Therefore, companies often have their own laboratories and trained personnel. For one of the most abundant and toxic mycotoxins, Ochratoxin A (OTA) we want to present an electrochemical detection system in which the read-out can be performed with a smartphone connected via Bluetooth to a miniaturized potentiostat. The recognition of OTA is performed with specific antibodies in a competitive assay format. Anti-OTA-antibodies were captured on magnetic beads on which the competitive binding between OTA and an OTA horseradish peroxidase (HRP) tracer was performed. To quantify OTA, the enzymatic reaction of the tracer with 3,3′,5,5′-tetramethylbenzidine (TMB) and H2O2 is employed. Oxidized TMB, which is enzymatically produced by the reduction of H2O2, is quantified by amperometry with screen-printed electrodes in a custom-made flow system. The results of the electrochemical detection method are in good correlation with the photometric detection of TMB. To demonstrate the applicability, we tested our system with OTA-spiked beer and performed the measurement via smartphone. T2 - 23rd JCF-Frühjahrssymposium 2021 CY - Online meeting DA - 29.03.2021 KW - Ochratoxin A KW - Cyclic voltammetry KW - Amperometry KW - Electrochemistry PY - 2021 N1 - Geburtsname von Riedel, Soraya: Höfs, S. - Birth name of Riedel, Soraya: Höfs, S. AN - OPUS4-52390 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chen, Xinyue A1 - Dong, Ximan A1 - Zhang, Chuyan A1 - Zhu, Meng A1 - Ahmed, Essraa A1 - Krishnamurthy, Giridharan A1 - Rouzbahani, Rozita A1 - Pobedinskas, Paulius A1 - Gauquelin, Nicolas A1 - Jannis, Daen A1 - Kaur, Kawaljit A1 - Hafez, Aly Mohamed Elsayed A1 - Thiel, Felix A1 - Bornemann, Rainer A1 - Engelhard, Carsten A1 - Schönherr, Holger A1 - Verbeeck, Johan A1 - Haenen, Ken A1 - Jiang, Xin A1 - Yang, Nianjun T1 - Interlayer Affected Diamond Electrochemistry N2 - Diamond electrochemistry is primarily influenced by quantities of sp3‐carbon, surface terminations, and crystalline structure. In this work, a new dimension is introduced by investigating the effect of using substrate‐interlayers for diamond growth. Boron and nitrogen co‐doped nanocrystalline diamond (BNDD) films are grown on Si substrate without and with Ti and Ta as interlayers, named BNDD/Si, BNDD/Ti/Si, and BNDD/Ta/Ti/Si, respectively. After detailed characterization using microscopies, spectroscopies, electrochemical techniques, and density functional theory simulations, the relationship of composition, interfacial structure, charge transport, and electrochemical properties of the interface between diamond and metal is investigated. The BNDD/Ta/Ti/Si electrodes exhibit faster electron transfer processes than the other two diamond electrodes. The interlayer thus determines the intrinsic activity and reaction kinetics. The reduction in their barrier widths can be attributed to the formation of TaC, which facilitates carrier tunneling, and simultaneously increases the concentration of electrically active defects. As a case study, the BNDD/Ta/Ti/Si electrode is further employed to assemble a redox‐electrolyte‐based supercapacitor device with enhanced performance. In summary, the study not only sheds light on the intricate relationship between interlayer composition, charge transfer, and electrochemical performance but also demonstrates the potential of tailored interlayer design to unlock new capabilities in diamond‐based electrochemical devices. KW - Nanocrystalline diamond KW - Interfaces KW - Electrochemistry KW - TOF-SIMS KW - SEM PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-621576 DO - https://doi.org/10.1002/smtd.202301774 SN - 2366-9608 VL - 9 IS - 2 SP - 1 EP - 10 PB - Wiley VHC-Verlag CY - Weinheim AN - OPUS4-62157 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Knoche, Lisa A1 - Lisec, Jan A1 - Schwerdtle, T. A1 - Koch, Matthias T1 - LC-HRMS-Based Identification of Transformation Products of the Drug Salinomycin Generated by Electrochemistry and Liver Microsome N2 - The drug salinomycin (SAL) is a polyether antibiotic and used in veterinary Medicine as coccidiostat and growth promoter. Recently, SAL was suggested as a potential anticancer drug. However, transformation products (TPs) resulting from metabolic and environmental degradation of SAL are incompletely known and structural information is missing. In this study, we therefore systematically investigated the formation and identification of SAL derived TPs using electrochemistry (EC) in an electrochemical reactor and rat and human liver microsome incubation (RLM and HLM) as TP generating methods. Liquid chromatography (LC) coupled to high-resolution mass spectrometry (HRMS) was applied to determine accurate masses in a suspected target analysis to identify TPs and to deduce occurring modification reactions of derived TPs. A total of 14 new, structurally different TPs were found (two EC-TPs, five RLM-TPs, and 11 HLM-TPs). The main modification reactions are decarbonylation for EC-TPs and oxidation (hydroxylation) for RLM/HLM-TPs. Of particular interest are potassium-based TPs identified after liver microsome incubation because these might have been overlooked or declared as oxidated sodium adducts in previous, non-HRMS-based studies due to the small mass difference between K and O + Na of 21 mDa. The MS fragmentation pattern of TPs was used to predict the position of identified modifications in the SAL molecule. The obtained knowledge regarding transformation reactions and novel TPs of SAL will contribute to elucidate SAL-metabolites with regards to structural prediction. KW - Salinomycin KW - Ionophore antibiotics KW - Transformation product KW - Electrochemistry KW - Rat/human liver microsomes KW - HRMS PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-542543 DO - https://doi.org/10.3390/antibiotics11020155 SN - 2079-6382 VL - 11 IS - 2 SP - 155 PB - MDPI CY - Basel AN - OPUS4-54254 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Devi, Sarita T1 - Metal-Organic Magnetic Framework-Based Immunosensor for Label-free Electrochemical sensing of NeuroToxin N2 - A metal-organic framework (MOF)-integrated microfluidic flow-cell (MFC) based electrochemical immunodetection of the tetanus toxoid (TT) is presented. The magnetic property of Fe-MOF helped to hold them on the working electrode (WE) at detection zone of MFC, surpassing the requirement of additional conjugation chemistry, and the conductive property was utilized to observe the change in signal efficiency in the presence of TT. The one-pot hydrothermal synthesis of iron-based MOF (Fe-MOF) was performed using the Fe3+/Fe2+ precursors as 1.2/1 mmol and dual ligands, tetrahydroxy-1,4-benzoquinone and 2 aminobenzene-1,4-dicarboxylic acid. The human anti-TT mAb SA13 was purified in-house from the cell culture supernatant of SA13 hybridoma cells by Protein-A affinity. SDS-PAGE showed the high purity as of a band just above the 140kDa mark in the eluate lane. The hydrodynamic radius of 5.35 nm and thermal unfolding temperature of 73°C were typical for antibodies. Indirect ELISA confirmed the high binding affinity. The mAb was conjugated on the Fe-MOF/Phe surface with the help of ethylenediamine (Fe MOF/Phe/EDA/anti-TTmAb). A specifically tailored MFC, made of Poly(methyl methacrylate) substrate was crafted at the BAM workshop. The limit of detection (LOD) and analytical sensitivity of the TT biosensor was 9.4 ng/ml [y=1.93E-5 + (-1.86E-6)x] and 11.6 μA/ng ml-1cm-2, respectively. The good reproducibility, selectivity, and stability show the applicability of these Fe-MOFs for detecting various other toxins. T2 - European Materials Research Society (E-MRS) Spring Meeting CY - Strasbourg, France DA - 26.05.2025 KW - Magnetic Metal-Organic Framework KW - Tetanus toxoid KW - Antibody KW - Electrochemistry KW - Biosensor PY - 2025 AN - OPUS4-63492 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Temgoua, Ranil C. T. T1 - Mimicking Environmental Degradation of Carbendazim Pesticide by EC-MS N2 - Currently, there is a growing interest in the study of environmental degradation pathways of organic contaminants such as pesticides, with the objective to better understand their potential risk for environmental systems and living organisms. In this context, DFT (conceptual density functional theory) and predictive methods may systematically be used to simplify and accelerate the elucidation of environmental degradation. We report herein the electrochemical behavior/degradation of the carbendazim (CBZ) fungicide widely used to treat cereal and fruit crops. Oxidative degradation of CBZ was studied using an electrochemical flow-through cell directly coupled to a mass spectrometer for rapid identification of CBZ degradation products. The structural elucidation of CBZ oxidation products was based on retention time, accurate mass, isotopic distribution and fragmentation pattern by using LC-HRMS an LC-HRMS2. The most important chemical reactions found to occur in the transformation of CBZ were hydrolysis and hydroxylation. EC-LC-MS and EC-MS analysis has made it possible to highlight the identification of degradation products of CBZ. In addition to previously known transformation products common to those observed during environmental degradation (monocarbomethoxyguanidine, benzimidazole-isocyanate, 2-aminobenzimidazole, hydroxy-2-aminobenzimidazole, hydroxycarbendazim, CBZ-CBZ dimer), two new degradation products were identified in this work: a quinone imine and a nitrenium ion. Electrochemistry mass spectrometry hyphenated techniques represent an accessible, rapid and reliable tool to elucidate the oxidative degradation of CBZ, including reactive degradation products and conjugates. T2 - 36th Topical Meeting of the International Society of Electrochemistry CY - Šibenik, Croatia DA - 26.05.2024 KW - Electrochemistry KW - Mass Spectrometry KW - Emerging pollutants KW - Transformation products PY - 2024 AN - OPUS4-61062 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Temgoua, Ranil C.T. A1 - Lisec, Jan A1 - Koch, Matthias T1 - Recent Advances in Electrochemical Analysis of Phenylurea Herbicides N2 - Phenylurea herbicides (PUHs) are extensively used in modern agriculture due to their high efficiency in weed control; however, their widespread application has led to persistent environmental contamination and growing public health concerns. Reliable, sensitive, and selective analytical methods are therefore essential for monitoring these compounds in environmental and food matrices. Although several recent reviews have addressed electrochemical sensors and biosensors for a broad range of pollutants, there is currently no dedicated review focusing exclusively on PUHs while integrating electrochemical sensors, biosensors, molecularly imprinted polymers (MIPs), and electrochemical detection coupled with liquid chromatography (LC). This review provides a comprehensive and critical overview of electrochemical strategies developed for the analysis of PUHs. Core electroanalytical techniques, including cyclic voltammetry (CV), differential pulse voltammetry (DPV), square wave voltammetry (SWV), and chronoamperometry (CA), are discussed in terms of their fundamental principles, analytical roles, and suitability for mechanistic investigation, quantitative determination, and rapid screening. Electrochemical impedance spectroscopy (EIS) is also examined, particularly for its application in the characterization of electrode interfaces and in electrochemical biosensor development. Furthermore, the integration of electrochemical methods with mass spectrometry is highlighted as a powerful approach for elucidating redox mechanisms and identifying electrochemical transformation products. More than one hundred electrochemical sensors and biosensors reported between 1993 and 2025 are critically evaluated, with emphasis on electrode materials, surface modification strategies, detection mechanisms, analytical performance, and applicability to real samples. The advantages and limitations of electrochemical sensors, biosensors, and MIP-based platforms are systematically discussed in the context of sensitivity, selectivity, response time, and matrix effects. By synthesizing current advances and identifying remaining challenges, this review aims to provide clear guidance for future research and to support the development of robust, efficient, and application-oriented electrochemical methods for PUHs analysis. KW - Mass Spectrometry KW - Phenylurea herbicides KW - Electrochemistry PY - 2025 DO - https://doi.org/10.1016/j.snr.2025.100431 SN - 2666-0539 VL - 11 SP - 1 EP - 67 PB - Elsevier B.V. AN - OPUS4-65286 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Temgoua Tonleu, Ranil C. A1 - Koch, Matthias T1 - Simulation of the Environmental Degradation of TBBPA by EC-LC-MS N2 - Oxidative degradation processes of tetrabromobisphenol A (TBBPA), a brominated flame retardant (BFR) in wood, plastics and electronics, were investigated by electrochemistry (EC) coupled online to electrospray ionization mass spectrometry (ESI/MS). Oxidative phase I and II metabolites production was achieved using an electrochemical flow-through cell equipped with a boron doped diamond electrode. Structural elucidation and prediction of oxidative metabolism pathways of TBBPA according to type II ipso-substitution were based on retention time, m/z ratio in negative mode and fragmentation pattern. Using the data obtained through high resolution MS analysis and the identification of single electron transfer (SET) as the initial step of a two-electron oxidation provided the necessary information to propose a mechanism for the electrochemical oxidation of TBBPA. Oxidation reactions involving aromatic hydroxylation and β-scission were the main degradation observed when studying the electrochemical behavior of TBBPA. Computational chemistry experiments using density functional theory (DFT) allowed to identify mono-hydroxylated reaction intermediate and dismissed the mechanism involving two concurrent hydroxylation. TBBPA oxidation products were compared to known metabolites of its biological and environmental degradation confirming the ability of electrochemistry to simulate β-scission reactions. T2 - Mass Spectrometry Forum 2024 CY - Vienna, Austria DA - 21.02.2024 KW - Emerging pollutants KW - Chemical characterization KW - Electrochemistry KW - Chemical and material safety KW - Mass spectrometry KW - Environment-material interactions PY - 2024 AN - OPUS4-59571 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Temgoua, Ranil C. T. T1 - Understanding the behavior of phenylurazoletyrosine- click electrochemical reaction N2 - The electrochemical behavior of 4-phenylurazole (Ph-Ur) was studied and the latter was used as a molecular anchor for the electrochemical bioconjugation of tyrosine (Y). Cyclic voltammetry (CV) and controlled potential coulometry (CPC) allowed to generate in situ from phenylurazole the PTAD (4-phenyl-3H-1,2,4-triazole-3,5(4H)-dione) species on demand for tyrosine electrolabeling. To evaluate the performance of tyrosine electrolabeling, coulometric analyses at controlled potentials were performed on solutions of phenylurazole and the phenylurazole-tyrosine mixture in different proportions (2:1, 1:1, and 1:2). The electrolysis of the phenylurazole-tyrosine mixture in the ratio (1:2) produced a charge of 2.07 C, very close to the theoretical value (1.93 C) with high reaction kinetics, a result obtained here for the first time. The products obtained were identified and characterized by liquid chromatography coupled to high-resolution electrospray ionization mass spectrometry (LC-HRMS and LC-HRMMS). Two products were formed from the click reactions, one of which was the majority. Another part of this work was to study the electrochemical degradation of the molecular anchor 4-phenylazole (Ph-Ur). Four stable degradation products of phenylurazole were identified (C7H9N2O, C6H8N, C6H8NO, C14H13N4O2) based on chromatographic profiles and mass spectrometry results. The charge generated during the electrolysis of phenylurazole (two-electron process) (2.85 C) is inconsistent with the theoretical or calculated charge (1.93 C), indicating that secondary/parasitic reactions occurred during the electrolysis of the latter. In conclusion, the electrochemically promoted click phenylurazole-tyrosine reactions give rise to click products with high reaction kinetics and yields in the (1:2) phenylurazole-tyrosine ratios, and the presence of side reactions is likely to affect the yield of the click phenylurazole-tyrosine reaction. T2 - Les Journées d’Électrochimie 2024 CY - Saint-Malo, France DA - 01.07.2024 KW - Electrochemistry KW - Mass Spectrometry KW - Simulation PY - 2024 AN - OPUS4-61063 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Scholl, Juliane A1 - Lisec, Jan A1 - Bagheri, Abbas A1 - Meiers, Emelie A1 - Russo, Francesco Friedrich A1 - Haase, Hajo A1 - Koch, Matthias T1 - Unveiling aging mechanisms of electrolytes in commercial end-of-life lithium-ion batteries N2 - In this study, 77 end-of-life (EOL) commercial lithium-ion batteries (LIBs) of various formats were systematically analyzed to investigate electrolyte degradation and the influence of pristine electrolyte compositions on aging behavior. Comprehensive chemical characterization was conducted using targeted and non-targeted mass spectrometry (MS), employing LC-MS/MS, GC-MS, and high-resolution MS (HRMS). This integrated approach enabled the identification of confirmed pristine components and complex degradation products. The results show that rechargeable pouch and cylindrical cells often deviate from conventional model systems, containing mixed lithium salt anions, ionic liquids (ILs), and high concentrations of triflates, triflimides, and bis(fluorosulfonyl)imide (FSI). These function as solvents, salts, or safety-enhancing additives. Specific IL degradation products were identified, and hypotheses formulated on previously unreported pathways. Furthermore, a novel series of oligomerization products of propylene carbonate (PC) was detected. In contrast, non-rechargeable coin cells revealed widespread use of per- and polyfluoroalkyl substances (PFAS) in their original electrolytes. Based on ex situ analyses, hypothetical PFAS degradation mechanisms are proposed here for the first time. The absence of carbonate oligomers and lithium salt-derived products, alongside the presence of standard carbonates, indicates lithium counterion coordination as a key factor in Lewis acid-catalyzed degradation. This study offers valuable insights into real-world battery aging. KW - Transformation products KW - Lithium-ion batteries KW - Fluorinated Compounds KW - Gas chromatography/ QTOF-MS KW - HILIC-LC-MS/MS KW - PFAS KW - Electrochemistry PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-644991 DO - https://doi.org/10.1016/j.jpowsour.2025.238613 SN - 0378-7753 VL - 661 SP - 1 EP - 10 PB - Elsevier B.V. AN - OPUS4-64499 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Temgoua, Ranil C. T. T1 - Voir les choses sous un autre angle : Comment l’électrochimie analytique aide à révolutionner l'analyse chimique N2 - As part of the "Journées de Chimie Analytique, JCA Dschang 2024", this plenary scientific conference will explore how analytical electrochemistry is fundamentally changing modern chemical analysis methods. We will highlight key innovations such as wearable/handheld sensors, lab-on-a-chip, lab-on-paper, lab-on-a-glove, integrated detection systems with artificial intelligence, and point-of-care (POC) technologies. We will also address the couplings between analytical electrochemistry and various analytical techniques such as mass spectrometry (EC-MS), chromatography (EC-LC), spectroscopy [EC-spectroscopy (UV-VIS, Raman, IR, NMR)], microscopy [EC-microscopy (EM, AFM)], and capillary electrophoresis (EC-CE). These advances enable faster, more accurate, and more accessible analyses, opening new perspectives for research and practical applications in environmental science, food and agriculture, public health, and advanced materials. T2 - Journées de Chimie Analytique 12th Edition CY - Dschang, Cameroon DA - 28.08.2024 KW - Organic Trace Analysis KW - Electrochemistry KW - Mass Spectrometry PY - 2024 AN - OPUS4-61064 LA - fra AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -