Analytical Research Forum 2023 (ARF23)

Analytical Research Forum 2023 (ARF23) 8 June 2023, London, UK and online

8 June 2023, London, UK and online Analytical Research Forum 2023 (ARF23) #ARF2023

Book of abstracts

Registered charity number: 207890

Introduction

Dear colleagues, Welcome to the 2023 Analytical Research Forum (ARF), the flagship event of the Royal Society of Chemistry Analytical Science Community. This year’s event is a hybrid one-day event in London and online, we have aimed for a high impact scientific symposium with high profile speakers and opportunities for early career researchers to present their work. This year we have included a career panel discussion to showcase careers in analytical chemistry. Once again, we have a wide range of talks and posters reflecting the enormous breadth of analytical chemistry in terms of techniques as well as the many important applications of those techniques. Analytical science has a vital role in so many areas of life and our meeting today is one of the ways in which we can share our knowledge and advance our field. There are opportunities to discuss and share research, and we encourage you to participate fully in the discussions and network with each other throughout the event. Many thanks are due to all our presenters for sharing their research with us today. I would also like to thank our sponsors and supporters and my colleagues on the Scientific Committee and the Royal Society of Chemistry staff who have worked hard to make this meeting possible. Most of all I’d like to thank all of you, the participants at this meeting and especially those of you at an early stage in your analytical careers for your energy, ideas and enthusiasm!

Diane Turner President Royal Society of Chemistry Analytical Science Community and Chair of the Scientific Organising Committee

Meeting information

This e-book contains abstracts of the posters presented at Analytical Research Forum ARF 2023 . All abstracts are produced directly from typescripts supplied by authors. Copyright reserved. All sessions, excluding the posters, are available to access via the virtual lobby. Further information on how to join the meeting and best practice for an online event is detailed in the joining instructions. Oral Presentations and Discussions All delegates at the meeting, not just speakers, have the opportunity to make comments or ask questions during the sessions. If you would like to ask a question during the discussion type ‘question’ or ‘comment’ into the chat box at the relevant point during the session. Networking sessions There will be regular breaks throughout the meeting for socialising, networking and continuing discussions started during the scientific sessions. During the networking sessions you will be able to join existing networking rooms or initiate one-to-one chats. Existing networking rooms will be visible from the virtual lobby. To create a one-to-one chat, simply click on the name of the person you would like to speak to and select if you would like to have a private or public conversation. For a public conversation, other delegates can join your chat room. You can participate in the networking sessions with other delegates in the InEvent app. On the web version, you can only be in one session at a time (this includes networking rooms). It is recommended to use the app if you want network during the sessions. Posters The posters will be available to view throughout the day and will be in person only. There will be two dedicated poster sessions during the day at 12.15 and at 14.35. We would ask poster presenters to be by their poster at these times to be able to talk about their poster. Oral and Poster abstract prize The best oral and poster abstract prizes will be awarded to the best submissions as judged during the symposium by members of the Scientific Organising Committee and Analytical Science Community Council.

Our thanks to the following prize sponsors: • Analytical Chemistry Trust Fund (ACTF) • Royal Society of Chemistry journal Analyst

• Royal Society of Chemistry journal Analytical Methods • Royal Society of Chemistry journal Chemical Science We invite all participants to vote for their top poster. Please submit your votes on the day using the ballot box provided. Winners will be announced in the closing remarks session at 17.15.

Careers Panel Discussion – Thursday 08 June, 11:25-12:15

Robert Bowles, Career and Professional Development Adviser at the Royal Society of Chemistry will be chairing the Careers panel as part of this year’s Analytical Research Forum activities. In this interactive and informal session our panelists will share their career stories and answer your questions which could include how to get the most out of connections, what they’ve learnt or would have done differently at the start of their career, how to develop career resilience and share tools and advice for managing uncertainty and making career choices.

Career Panelists

Robert Bowles Royal Society of Chemistry, UK

After an early research career in marine biotechnology, Robert moved out of the lab, gaining five years’ experience in sales and marketing of educational software to schools. He joined the Royal Society of Chemistry sixteen years ago, and has managed a program of their successful education and careers projects. He recently provided careers input into the new RSC Pathfinder CPD planning and recording tool for members launching in Jan 2023 . https://pathfinder.rsc.org. As a qualified careers adviser, he currently works in the Royal Society of Chemistry’s Career Management team; offering careers advice to our membership and the wider chemistry community. www.rsc.org/careers

May Copsey Royal Society of Chemistry, UK

May Copsey is currently the Executive Editor for Royal Society of Chemistry’s flagship journal, Chemical Science. She joined the Royal Society of Chemistry in 2006 as an Assistant Editor and has worked on a variety of different journals during this time, including Dalton Transactions, CrystEngComm and Journal of Materials Chemistry. She was Executive Editor for the Analytical portfolio of journals for four years, before moving to take over the General Chemistry portfolio, including Chemical Science, ChemComm and Chemical Society Reviews in 2015. She has had the pleasure of leading an editorial team dedicated to Chemical Science since June of 2018. May is a main group chemist by training, as before joining the RSC she worked for three years as Post-doctoral Research Associate at the University of Calgary, after completing a PhD in main group chemistry at the University of Bristol.

Mark Parkin Eurofins Forensic Services, UK

Mark Parkin heads up the Toxicology Laboratory at Eurofins Forensic Services and is a Visiting Senior Lecturer at King’s College London. He is responsible for the day-to-day operation of the UK’s largest forensic toxicology laboratory that covers around 95% of the forensic toxicology casework in England and Wales. He has oversight of a team of 35 forensic chemists undertaking the analysis of around 2,000 casework samples per month. He is the former chair of the London Toxicology Group and the London Biological Mass Spectrometry Discussion Group and has spent the past twenty years working in the field of evidential analysis using mass spectrometry as the principal analytical tool. His current interests are introducing full end-to-end automation to the forensic bioanalytical process and the use of machine learning for the processing of forensic data.

Vicky Hilborne University College London, UK

Dr Victoria Hilborne is a Lecturer (Teaching) at University College London (UCL), Department of Chemistry, her career spans both academia and industry. Her particular interests are embedding sustainability in chemistry education, developing analytical chemistry and data evaluation skills. Her research interests are analytical method, sensor development, data modelling and analytics in industrial processes and the environment. Vicky was awarded a BSc in Environmental Chemistry from Edinburgh University and did her PhD at London South Bank University with the Fire and Explosion research group on measuring and modelling contaminant dispersion in ventilated indoor air. She won a Pexa Award for her publication on this topic. She also gained a PGCHE qualification from London South Bank University. After leaving school, Vicky worked in paint manufacture quality control, then shampoo product development, while studying part time for a BTec HNC Chemistry. After graduating from Edinburgh University, she was a research assistant for the Institute of Terrestrial Ecology studying rural ozone then became a Health and Safety Scientist for Brewing Research International. She then worked at London South Bank University, running the analytical facilities, part time lecturer and studying part time for her PhD. Vicky was awarded a UCL Provost Teaching Award for excellence in teaching and learning in 2021.

About the RSC Analytical Science Community The Analytical Science Community is one of seven Science Communities of the Royal Society of Chemistry (RSC) which its Members can join. Each community encourages, assists and extends the knowledge and study of their discipline. The Analytical Science Community has around 11,000 members from across industry and academia across all career stages and is led by a Community Council elected by the membership to represent the analytical sciences community. Analytical Science Community activities include: • Organising an annual Analytical Research Forum • Supporting community-led scientific meetings and workshops • Recognising outstanding contributions to analytical science through our Prizes and Awards programme • Running the annual Schools’ Analyst competition with support from the Analytical Science Community Regions and funded by the Analytical Chemistry Trust Fund You can keep up to date with all our activities through our newsletter Analytical Matters . RSC members can join the Analytical Science Community by updating their details in the “My communities and subscriptions” tab of the My membership section of the online RSC membership area. Please visit the Members’ area Sign In (rsc.org) and add to your list of community groups. There is no additional charge for this membership. Find out more about us and our activities at Analytical Science Community (rsc.org) Analytical Methods Committee (AMC) Made up of Expert Working Groups (EWGs) and designated representatives, the AMC aims to participate in national and international efforts to establish a comprehensive framework for appropriate quality in chemical measurement by: • Assisting with the development and establishment of suitable performance criteria for analytical methods and instrumentation • Advising on the use and development of appropriate analytical methods • Working alongside accreditation services and governing bodies, such as DEFRA, the FSA and UKAS, to ensure best analytical practice •

Producing reports and Technical Briefs on a wide range of analytical topics to support continuing professional development (CPD) • Read more about the Analytical Methods Committee (rsc.org)

Supporters of the Analytical Science Community

Analytical Chemistry Trust Fund The ACTF is a charity established for the purposes of promoting, assisting and extending the science and study of Analytical Chemistry and of all questions relating to the analysis, nature and composition of natural and manufactured materials for the benefit of the public. Find out more about ACTF activities here.

Oral presentations

Online TGA-GCMS: a novel method for detecting tyre wear particles in road dusts Daniel Baqer University of Surrey, UK The makeup of makeup: Spectroscopic characterisation of facial cosmetics as associative trace evidence Katy Bruce University of Kent, UK Development of an industrial high throughput co-crystal screening workflow Jacob Danks Pharmaron UK, UK An electrochemical ovalbumin immunosensor based on nanocellulose and MXene nano-famework Faheem Kareem Universiti Brunei Darussalam, Brunei Darussalam

HPLC-ICP-MS and post-column isotope dilution analysis of the Fe protein profile for differential diagnosis of stroke: application to nasal

exudate and serum Marta Marina Latorre University of Oviedo, Spain

Imaging NMR for the quantitative study of protein-ligand interactions and enzymatic reactions in a single NMR tube Serena Monaco School of Pharmacy - University of East Anglia, UK NMR and MS analysis of 15N-labelled complex mixtures: investigation of chloramine disinfection by-products Justinas Sakas University of Edinburgh, UK Biosensor for rapid measurement of lactate in exhaled breath condensate Shulin Zhang Imperial College London, UK

Poster presentations

P01

A new GC-HRMS method for screening of phthalate esters and bis (2-ethylhexyl) adipate (DEHA) in atmospheric particles

Cristian Ryan Argamino Coventry University, UK

P03

Fast pKa determination for lead optimisation. Application of chemical shift imaging and chemical gradients into analysis of APIs. Krzysztof Baj University of Liverpool, UK Lead isotope ratio measurements of airborne particulates using ICP-MS/ MS for source attribution Hau Lam Jody Cheong National Physical Laboratory, UK Evaluation of pollution load on contaminated land in north east England using an unmanned aerial vehicle with a multispectral image camera John Dean Northumbria University, UK Use of machine learning for monitoring the growth stages of an agricultural crop informed by derived vegetation indices and spatial and temporal soil analyses. John Dean Northumbria University, UK Broadband cavity enhanced uv-vis absorption spectroscopy for picolitre liquid samples Worth Imogen Fermor-Worth University of Exeter, UK A new on-line SPE LC-HRMS method for simultaneous analysis of selected emerging contaminants in surface waters Omotola Folorunsho Centre for Agroecology and Water Resilience, Coventry University, UK Quick detection of interleukin-6 using functionalised gold nanoparticles Maria Gomes de Pinho Baptista University of East Anglia, UK

P04

P05

P06

P07

P08

P09

P10

Decoupling protein concentration and aggregate content using diffusion and water NMR Mark Grimes University of Cambridge, UK Introduction of a simple and effective analytical method for haloacetic acids in drinking water by reverse phase LC-MS/MS Polly Grundy Cranfield University, UK Mass spectroscopy: life at the interface. Hyphenated parallel (FTIR)-MS for unambiguous ID in complex samples Nathan Hawkins Spectrometrics Limited, UK Method for determining pKa of invisible small molecules using spatially resolved 1H NMR through pH gradient and proton absorption parameters alone Haider Hussain University of East Anglia, UK Electrochemical characterisation of actinorhodin from S. coelicolor culture extracts Perrine Lasserre University of Strathclyde, UK Development and use of simulated instruments to teach mass spectrometry to undergraduates Lavinia Mbongo Loughborough University, UK Comparison of chiral chromatography on SFC, and normal and reverse phase Ciara O'Doherty, presented by Josh Freem Pharmaron, UK Alternative methods for determining the nutritional effects of foods on the body Aliyah Saifuddin King's College London, UK Towards carbonate detection with a distance-based paper analytical sensor Zakia Tebetyo University of Hull, UK

P11

P12

P13

P15

P16

P18

P19

P20

P21

Measurement of the pKa values of organic molecules in aqueous-organic solvent mixtures by 1H NMR without external calibrants Matthew Wallace University of East Anglia, UK The application of LA-ICP-MS for quantified, high spatial resolution imaging of Pb isotopes in ferromanganese crusts Nathan Westwood Loughborough University, UK

P22

Online TGA-GCMS: A novel method for detecting tyre wear particles in road dusts Daniel Baqer 1 , Kieran Evans 2 , Patrick Sears 1 , Maya Al Sid-Cheikh 1 1 University of Surrey, UK, 2 PerkinElmer, Beaconsfield, UK The production of tyre wear particles (TWPs) from the abrasion of vehicle tyres on road surfaces has gained worldwide attention as it may be the primary source of microplastic pollution in the environment. However, the current reported experimental data contradicts these estimates of TWP emissions in the environment. This inconsistency may be due to a lack of environmental presence or an inadequacy in detection resulting from a lack of standardization in methodologies and the fact that TWPs do not respond well to conventional microplastic separation and detection techniques. In this study, we propose a method for identifying TWPs in road dust by online coupling of a thermogravimetric analyser (TGA) and gas chromatography mass spectrometry (GCMS) for rapid, high-throughput, and automated analysis. Various thermal degradation products of rubber elastomers were discovered in different car tyre brands, serving as common markers for TWP. Examination of the treads and sidewalls revealed unique rubber compositions that could indicate the origin of the rubber fragments. Additional analyses of road dust samples from two major UK highways and various roads in the London congestion zone verified the presence of TWP. This approach requires minimal to no sample preparation, lowering the risk of sample loss or contamination and reducing data variability among researchers that employ different sample preparation methods.

The makeup of makeup: spectroscopic characterisation of facial cosmetics as associative trace evidence Katy Bruce 1 , Simon W. Lewis 2 , Georgina Sauzier 2 , Donna Arnold 1 1 University of Kent, UK, 2 Curtin University, Perth, Australia Microtraces of a wide range of physical materials have been used in forensic casework to provide evidence of association, yet cosmetic microtraces remain underutilised 1 . It is highly likely that cosmetic microtraces will be transferred between people, locations, and objects in the course of criminal activity; this is particularly true during violent crimes. Therefore, these traces could provide a valuable form of associative trace evidence, especially where the cosmetic source is particularly distinctive, or products have been layered, resulting in unique combinations. Furthermore, cosmetic microtraces may allow interpretation of the circumstances of the transfer event, thus aiding reconstruction of the crime. Cosmetic use is independent of age, gender, ethnicity, and socio- economic status, making research in this area a globally relevant endeavour. Nonetheless, it is vital that cosmetic microtraces are comprehensively investigated and understood in order to be fully integrated into the criminal justice system. Violent crime is a significant societal issue; accordingly, any underutilised forms of trace evidence that might aid an investigation, should be exploited. This research aims to chemically characterise and compare a substantial selection of decorative facial cosmetics (foundation) for forensic purposes, and assess the impact of sample ageing. The composition of cosmetic products is complex, meaning their analysis benefits from a robust multi-technique approach. Light microscopy and Raman spectroscopy are used as the principal analytical techniques, complemented by infrared spectroscopy, X-ray fluorescence, X-ray diffraction, and scanning electron microscopy. To the best of the authors’ knowledge, this is the first study that combines the use of Raman spectroscopy with this cosmetic subclass. The results obtained are combined with chemometric methods to allow discrimination and classification according to cosmetic brand, type, or formulation, and to limit operator subjectivity and unconscious bias. Thereafter, an extensive collection of used sample spectra will be projected onto these chemometric models to identify trends within the data. Our research has highlighted significant differences in sample homogeneity – this is critical information for building interpretation frameworks – and a high spectral variability among samples. It is hoped that this research will increase awareness of and encourage acceptance of cosmetic microtraces in forensic casework, and initiate discussions on the most suitable methods of cosmetic microtrace recovery in the future. References 1. R.Chophi, S.Sharma, S.Sharma and R.Singh. Forensic Chemistry, 2019, 14: 100165

Development of an industrial high throughput co-crystal screening workflow

Jacob Danks Pharmaron UK

One of the challenges faced by the pharmaceutical industry in the development of APIs (active pharmaceutical ingredients) is poor biorelevant solubility, which can lead to low bioavailability and hence affect the efficacy of the drug. 1 Typically, formation of a salt between the API molecule and a counterion is used as a method of improving the solubility, 2 however in cases where there is no ionisable functional group on the molecule, or salt formation is unsuccessful, co-crystal formation can be utilised. 3 A co-crystal is defined as a single phase solid where two or more different components are present, generally in a stoichiometric ratio, and is not a solvate or simple salt. 4 High throughput co-crystallisation experiments have recently begun development, typically centred around a multi-well plate, much like those employed in polymorph and salt screens. 5 However progress has been hindered by the number of variables associated with cocrystal formation, and so far there has been little attention paid to considerations associated with cocrystal screening in an industrial setting. 6 Through this investigation, a variety of high throughput co-crystallisation methods were performed on model co-crystal systems with carbamazepine, including evaporative crystallisation, resonant acoustic mixing and slurry crystallisation. Both the effectiveness of each co-crystallisation method and the feasibility of implementing it into a screening workflow based on key industrial requirements (e.g. material quantity and time), alongside its ability to be scaled up to enable further characterisation, were considered in the design of the workflow. The comparison of these methods led to the outlining of a high throughput co-crystal screening workflow that was then demonstrated on sulfasalazine, an example of a BCS Class IV API. 7 References

1. K. T. Savjani, A. K. Gajjar and J. K. Savjani, ISRN Pharmaceutics, 2012, 2012, 1–10. 2. D. Gupta, D. Bhatia, V. Dave, V. Sutariya and S. Varghese Gupta, Molecules, 2018, 23. 3. S. S. Buddhadev and K. C. Garala, Proceedings, 2020, 62, 14. 4. S. Aitipamula et al, Crystal Growth & Design, 2012, 12, 2147–2152.

5. T. Kojima, S. Tsutsumi, K. Yamamoto, Y. Ikeda and T. Moriwaki, International Journal of Pharmaceutics, 2010, 399, 52-59. 6. V. Luu, J. Jona, M. K. Stanton, M. L. Peterson, H. G. Morrison, K. Nagapudi and H. Tan, International Journal of Pharmaceutics, 2013, 441, 356-364. 7. S. Clarysse, J. Brouwers, J. Tack, P. Annaert and P. Augustijns, European Journal of Pharmaceutical Sciences, 2011, 43, 260–269.

An electrochemical ovalbumin immunosensor based on nanocellulose and MXene nano-famework Faheem Kareem, Minhaz Uddin Ahmed Universiti Brunei Darussalam, Brunei Darussalam A versatile and highly sensitive sensing platform based on nanocellulose (NCs) and MXene nanocomposite has been developed at the surface of glassy carbon electrode for ovalbumin (Ova) detection. Firstly, the dialdehyde group was introduced onto the surface of nanocellulose before being decorated with MXene nanosheet. Ovalbumin antibody was immobilized on the surface of functionalized NCs through the covalent bonding between amino groups of Ova and dialdehyde group of NCs. Moreover, the incorporation of MXene nanosheets can increase the electrochemical signal due to their high electrocatalytic characteristics, high specific surface area, outstanding electrical conductivity, and good biocompatibility. Key processing variables including antibody concentration, antibody binding time, pH, and time required for immunocomplex formation were optimized. Ova was electrochemically detected by using Differential Pulse Voltammetry (DPV) in 5mM K 3 Fe(CN 6 ) as a redox probe. The fabricated immunosensor exhibited higher sensitivity to Ova under optimal conditions, with a linear range of 0.01 pg/mL to 100 ng/mL and limit of detection (LOD) of 0.57 fg/ml. This novel immunosensor also demonstrated high selectivity, reproducibility, interference resistance and achieved excellent recoveries of Ova detection in spiked real food samples, displaying the potential applicability of the designed immunosensor. References 1. Shao, Y., et al., Two-dimensional MXene nanosheets (types Ti3C2Tx and Ti2CTx) as new ion-to-electron transducers in solid-contact calcium ion-selective electrodes. 2019. 186 (12): p. 1-9. 2. Zhang, Z., et al., Self-reduction synthesis of new MXene/Ag composites with unexpected electrocatalytic activity. 2016. 4 (12): p. 6763-6771.

HPLC-ICP-MS and post-column isotope dilution analysis of the Fe protein profile for differential diagnosis of stroke: application to nasal exudate and serum Marta Marina Latorre 1 , Marta Aranaz 1 , Claudia García-Revuelta 1 , Lara Lobo 1 , Héctor González-Iglesias 2 , Carmen García-Cabo 3 , Estefanía Costa-Rama 1 , M. Teresa Fernández-Abedul 1 and Rosario Pereiro 1 1 Department of Physical and Analytical Chemistry, University of Oviedo, Spain, 2 Department of Technology and Biotechnology of Dairy Products, IPLA-CSIC, Spain, 3 Central University Hospital of Asturias, Oviedo, Spain According to The World Health Organization (WHO) the cerebrovascular accident (CVA), or stroke, is the second cause of death worldwide. There is also a high morbidity associated with this pathology: about 50% of survivors end up chronically disabled. CVA can be classified as ischemic (caused by a blood clot) or hemorrhagic (produced by broken blood vessels), both causing a decrease in the blood flow to the brain. It is crucial a fast diagnosis of the CVA-type in order to start the proper treatment and thus to achieve a better recovery of the patients. Direct clinical parameters associated with the CVA in the brain is rather limited due to this organ is highly immunoprotected by the blood-brain barrier. However, the recent description of a lymphatic drainage from the brain to the nasal mucosa paves the way to investigate nasal exudate to provide information about CVA, being observed noticeable differences in total Fe concentration when comparing ischemic and hemorrhagic patients [1]. In this context, and aiming at the search of potential biomarkers allowing for a fast differential diagnosis of CVA, we have investigated the potential differences in the protein profile of Fe (this element is well known to be linked with CVA) between ischemic and hemorrhagic stroke patients. For such aim, a method based on size exclusion chromatography (SEC-HPLC) coupled to ICP-MS and quantitative analysis via post-column isotope dilution (IDA) has been developed for two types of biological fluids: serum (most common fluid used in diagnosis) and nasal exudate (as a source of direct information from the brain), and results compared for ischemic and hemorrhagic CVA patients as well as for controls. In addition, elemental analysis of iron concentrations has been carried out for both biological fluids. References 1. C. García-Cabo, P. Llano-Suarez, Clin. Chem. Lab. Med., 2019 , 58, 847-853.

Imaging NMR for the quantitative study of protein-ligand interactions and enzymatic reactions in a single NMR tube Serena Monaco 1 Jesus Angulo 2 , Matthew Wallace 1 1 University of East Anglia, UK, 2 Instituto de Investigaciones Químicas (IIQ), Spain NMR is a powerful tool to study protein-ligand complexes as it unveils atomic details of the interactions (and enzymatic reactions) in solution, while also allowing fully quantitative approaches, such as determination of binding dissociations, K D ‘sby titration of a protein with increasing concentrations of ligand. 1 Imaging NMR is a new technique enabling us to condense any titrations in a single NMR tube containing a gradient of the analyte of interest, extracting accurate parameters in a small fraction of the experimental time and material required for the manual approach. 2 Imaging NMR has the huge potential of accelerating drug discovery and fundamental research. We aimed at the development of: 1) K D and binding specificity, through the newly implemented Imaging Saturation Transfer Difference (STD) NMR experiment; and 2) the determination of enzymatic parameters K M and V Max from fitting the Michalis Menten equation. Both implementations are performed in a single NMR tube, with a huge reduction of time and resources compared to conventional methodologies. We prepare samples containing a controlled gradient of ligand against homogeneous concentration of protein, and developed for the first time Imaging STD NMR to obtain the K D of the complexes in a single tube. For 2) we prepared substrate gradients against homogeneous enzymes to extract K M and V Max . We prove that 1) Imaging STD NMR is an effective methodology to extract dissociation constant, obtaining values in good agreement with literature in 10%-20% of the experimental time relative to the manual STD NMR titration. Using the same approach, we can also assess the specificity of binding, following the evolution of the binding epitope upon increasing ligand excess. 3 We also demonstrated that 2) by Imaging NMR we can condense enzymatic assays in a single NMR tube. Whereas UV spectroscopy is the established technique for this, its main limitation is the need of a chromogen, often precluding direct detection and/or excluding physiological substrates. By Imaging NMR we manage to obtain accurate K M and V Max in a single sample and with no limitation on the nature of substrate. 4 References 1. J. Angulo, et al. Chemistry–A European Journal 16.26 (2010): 7803-7812. 2. M. Wallace, et al. Analytical chemistry 90.6 (2018): 4160-4166.

3. S. Monaco et al. Submitted. 4. S. Monaco et al. Unpublished.

NMR and MS analysis of 15N-labelled complex mixtures: investigation of chloramine disinfection by-products Justinas Sakas, Maria Vorka and Dušan Uhrín University of Edinburgh, UK

Chloramination is a water disinfection method used around the world to provide potable water. The addition of chloramine (NH 2 Cl) kills pathogens, however it also reacts with naturally dissolved organic matter (DOM) and anthropogenic contaminants to produce a complex mixture of disinfection by-products (DBPs), which are known to be cytotoxic, genotoxic and carcinogenic. 1 Although the level of some of these compounds is regulated, the majority of by-products are unregulated and more than 70% of chloramination DBPs are unknown. 2 Additionally, it has been shown that the total toxicity of DBPs cannot be accounted by regulated compounds alone. 3 Therefore, it is necessary to elucidate the structures of all DBPs in order to find out if they pose any health risks. Unfortunately, the structure elucidation of complex mixtures is an arduous task as they contain hundreds or even thousands of compounds that cannot be easily separated using chromatographic techniques. Fourier- transform ion cyclotron resonance mass spectrometry (MS) offers extremely high sensitivity and resolution and thus can be used for untargeted analysis of complex mixtures, bypassing the customary chromatographic step. To complement the information obtained from mass spectra, nuclear magnetic resonance (NMR) spectroscopy can be used to provide detailed structural information. NMR analysis of complex mixtures can be simplified by targeting specific moieties present in a subset of molecules in order to achieve spectroscopic ‘separation’. Recent examples include structure elucidation using NMR experiments designed for compounds tagged with −O 13 CH 3 and fluorinated compounds. 4,5 In this work, we have implemented new MS formula assignment procedures using the CoreMS Python library 6 for compounds containing halogens and 15 N atoms without the need for comparison to unlabelled data. Information about the reaction types occurring during chloramination is extracted from the detected molecular formulae using various statistical techniques, including the PageRank algorithm (also used by Google to rank search results). 7 Finally, new NMR experiments were designed to aid structure elucidation of 15 N-containing DBPs, such 1 H, 15 N constant-time HMQC-COSY in which proton-proton correlations are obtained between adjacent CH and 15 NH groups. We believe this suite of new methods will be applicable to other fields analysing 15 N-labelled mixtures, such as metabolomics. References 1. X. Li and W. A. Mitch, Environ. Sci. Technol. , 2018, 52 , 1681–1689. 2. G. Hua and D. A. Reckhow, Water Res. , 2007, 41 , 645–651. 3. R. Mian, G. Hu, K. Hewage, M. J. Rodriguez and R. Sadiq, Water Res. , 2018, 147 , 112–131. 4. N. G. A. Bell, A. A. L. Michalchuk, J. W. T. Blackburn, M. C. Graham and D. Uhrín, Angew. Chem. Int. Ed. , 2015, 54 , 8382–8385. 5. A. J. R. Smith, R. York, D. Uhrín and N. G. A. Bell, Chem. Sci. , 2022, 13 , 3766–3774. 6. Y. E. Corilo, W. R. Kew and L. McCue, EMSL-Computing/CoreMS: CoreMS 1.0.0, 2021. 7. Zenodo. DOI: 10.5281/zenodo. 4641553.L. Page, S. Brin, R. Motwani and T. Winograd, The PageRank Citation Ranking: Bringing Order to the Web , The Web Conference, 1998.

Biosensor for rapid measurement of lactate in exhaled breath condensate Shulin Zhang and Danny O'Hare Imperial College London, UK Lactate concentration plays an important role in disease diagnostics. Higher lactate concentrations are associated with sepsis and septic shock [2] , trauma [3] , tissue hypoxia due to acute lung injury [4] , and respiratory diseases [5] . Lactate level is also widely used in monitoring athletes’ training and fitness as long-term exhausting exercise leads to a rapid increase in lactate level and result in muscle weakening and fatigue [6] . Compared with the traditional blood sample media which is invasive and capillary blood monitoring is not suitable for routine clinical use, the exhaled breath condensate (EBC) is simple and non-invasive method with no potential for adverse effects for lactate analysis. In this presentation, a point-of-care electrochemical biosensor is introduced for the EBC lactate analysis. This disposable and low-cost sensor is aimed to be inserted in an EBC collection device developed by our team that enables real-time monitoring and rapid measurements of EBC lactate level. The sensor measurement is done directly after EBC sample collection, that minimizes the risk of sample degradation and is cheaper than the traditional laboratory techniques such as fluorometry or mass spectrometry. The sensor is modified with poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS), Prussian blue (PB) and lactate oxidase (LOD) enzyme. Lactate concentration is measured from amperometric current response generated by the redox reactions on sensor surface. The enzyme gel formulation is optimized based on rotating disk electrode (RDE) experiments and kinetics analysis, investigating the effect of LOD concentration and gel thickness, and was then applied to disposable sensors. Finally, human EBC analysis is conducted on healthy subjects at rest and after 30 min of intense aerobic cycling exercise. Sensor’s results in real EBC lactate measurements demonstrate a good correlation with fluorometry and mass spectrometry calibrations and exhibit high stability and sensitivity in both short-term and long-term use. Mass production of the sensor is done by robotic gel dispensing using a Biodot aspirate dispensing machine. Note: This presentation is based on the corresponding author's recent publication ‘Rapid Measurement of Lactate in the Exhaled Breath Condensate: Biosensor Optimization and In-Human Proof of Concept’ in ACS Sensors (doi.10.1021/acssensors.2c01739) [1] References 1. Zhang, S. Rapid Measurement of Lactate in the Exhaled Breath Condensate: Biosensor Optimization and In-Human Proof of Concept. ACS Sens. 2022 . 2. Arnold, R. C. Multicenter study of early lactate clearance as a determinant of survival in patients with presumed sepsis. Shock 2009 , 32 , 35-39. 3. Régnier, M. Prognostic Significance of Blood Lactate and Lactate Clearance in Trauma Patients. Anesthesiology 2012 , 117 , 1276-1288. 4. Rathee, K. Biosensors based on electrochemical lactate detection: a comprehensive review. Biochemistry and biophysics reports 2016 , 5 , 35-54. 5. De Backer, D. Lactate Production by the Lungs in Acute Lung Injury. Am J Respir Crit Care Med 1997 , 156 , 1099-1104. 6. Marek, E. M. Measurements of lactate in exhaled breath condensate at rest and after maximal exercise in young and healthy subjects. J. Breath Res. 2010 , 4 , 017105.

A new GC-HRMS method for screening of phthalate esters and bis(2-ethylhexyl) adipate (DEHA) in atmospheric particles Cristian R. A. Argamino 1,2 , Anna Bogush 1 , Svetlana Stevanovic 2 and Ivan Kourtchev 1 1 Coventry University, UK, 2 Deakin University, Australia Phthalate esters (PAEs) and bis(2-ethylhexyl) adipate (DEHA) are ubiquitous chemicals often used as plasticizers in consumer and industrial products. Scientific evidence has linked these compounds to several human diseases (i.e., reproductive, cardiovascular, neurological, respiratory). Thus, the level of certain PAEs (e.g., di-n-butyl phthalate (DBP), and bis(2-ethylhexyl) phthalate (DEHP) are regulated in plastic products, toys, drinking water, and water bodies. Meanwhile, other PAEs (e.g., di-n-octyl phthalate (DOP)) are often used as substitutes but were recently added to a list of new and emerging pollutants (NEPs) due to their potential adverse toxic effects. There is growing concern on the occurrence of PAEs in inhalable particles since regulatory bodies have not set limits on their atmospheric levels. PM 2.5 (particulate matter with aerodynamic diameter < 2.5 µm), which can be enriched with PAEs, has the potential to elicit multi-system human toxicity as they can reach extrapulmonary tissues like the heart, intestines, and reproductive system through blood circulation. The aim of the work is to develop and validate a sensitive GC-HRMS method that can be used for the targeted screening of regulated PAEs (i.e., DBP, DEHP, benzyl butyl phthalate (BBP)) including DEHA, and PAEsthat are considered as NEPs (i.e., dimethyl phthalate (DMP), diethyl phthalate (DEP), and DOP), in PM 2.5. Gas-chromatography high-resolution mass (GC- HRMS) is commonly used for untargeted analysis but has the potential to be applied for targeted screening of trace pollutants in complex environmental samples. Analytical aspects that are important for implementing this method have been assessed, including the selection of extraction solvents, pre-concentration steps, and GC injector parameters to reduce matrix effects. High sensitivity and selectivity of the method was achieved by optimizing MS/MS parameters including widening the quadrupole isolation window and increasing multiplex count. Method provided good linearity for all analytes (i.e. r 2 >0.99) across a wide linear range (up to 0.5 ng/uL). The method passed the accuracy and precision test across four concentration levels (i.e., within +/- 20 %RE and %CV). The method was successfully applied for the screening of PM 2.5 samples from an urban environment (City of Curitiba, Paraná, Brazil) where several PAEs (including those belonging to NEPs) were detected above the LOD.

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Fast pKa determination for lead optimisation. Application of chemical shift imaging and chemical gradients into analysis of APIs Krzysztof Baj 1 , Alexandra Hindle 2 , Stephen P. Marsden 2 , James Brammer 1 , Nichola Davies 3 , Sylvain Demanze 3 , Matthew Wallace 4 , Jonathan A. Iggo 1 1 University of Liverpool, UK , 2 University of Leeds, UK , 3 Oncology R&D, AstraZeneca, UK , 4 University of East Anglia, UK H Chemical Shift Imaging 1 with a chemical gradient (CSI-CG) provides an efficient, one-shot method for the determination of pKa. 2 This Poster will describe its application to measurements in DMSO-d6 for the purpose of understanding basicity patterns in homologous series of bridged anilines followed by density-functional theory(DFT) geometry optimisation, Figure 1. 3,4 Several pulse sequences for water suppression have been evaluated, and automation routines developed to allow the use of sample changers for high throughput of data acquisition in an industrial setting. 5 Water signals are suppressed using excitation sculpting, while pre-saturation can be used to suppress a second solvent peak if required, Figure 2. That allowed method extension to mixed solvents with zero organic solvent extrapolation and obtaining pKa aq for poorly water-soluble analytes using little material. Employing 19 F would streamline the data processing of particularly complex analytes with very crowded 1 H spectra. This requires the simultaneous acquisition of both 1 H and 19 F images, i.e. a multi-receiver instrument not available to the group. We have, therefore, adopted an alternative approach in which an HFH sandwich is acquired. The pH in each slice of the 19 F-CSI is obtained by interpolation from two 1 H-CSI experiments. Finally, we explore adapting the one-shot method to study pH and solvent-dependent conformational changes. The project's ultimate goal is to provide a tool for measuring multiple structural properties in a function of any variable if the gradient of the latter is obtainable in an NMR tube.

Figure1. Reduced electrostatic potential on bridged anilines free electron pair in homologous series follows the drop in measured pKa value using CSI-CG.

Figure 2. Pulse sequence for double solvent suppression 1 H Chemical Shift Imaging. References 1. P. Trigo-Mourino, C. Merle, M. R. Koos, B. Luy and R. R. Gil, Chemistry, 2013, 19, 7013-7019.M. Wallace, D. J. Adams and J. A. Iggo, Anal. Chem., 2018, 90, 4160-4166. 2. A. D. Bochevarov, E. Harder, T. F. Hughes, J. R.Greenwood, D. A. Braden, D. M. Philipp, D. Rinaldo, M. D. 3. Halls, J. Zhang and R. A. Friesner, Int. J. Quantum Chem. 2013, 113, 2110-2142; Schrödinger Release 2023-1: Maestro, Schrödinger, LLC, New York, NY, 2021. 4. Hindle, A., Baj, K., Iggo, J., Cox, D., Pask, C., Nelson, A., Marsden, S., 2023. Modular Synthesis of Bicyclic Twisted Amides and Anilines. https://doi.org/10.26434/chemrxiv-2023-g1b0dG. Schenck, K. Baj, J. A. Iggo and M. Wallace, Anal. Chem., 2022, DOI: 10.1021/acs.analchem.2c00200.

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Lead isotope ratio measurements of airborne particulates using ICP-MS/MS for source attribution Hau Lam Jody Cheong, Emma C. Braysher, Richard J.C. Brown, Andrew S. Brown National Physical Laboratory, UK Heavy metal pollution is a serious environmental problem that affects humans, animals, and other organisms. With the growth of environmental awareness around the globe, monitoring and controlling the levels of heavy metals in airborne particulates has become an important activity. In addition to running the UK Heavy Metals Monitoring Network for the Environment Agency and Department for Environment, Food and Rural Affairs for regulatory compliance, NPL has developed isotope ratio measurement methods for airborne particulate samples with the use of tandem inductively coupled plasma mass spectrometry (ICP-MS/MS) to provide information about the sources of the pollution. Although leaded petrol is banned in the UK and ambient concentrations have subsequently dropped over the past 20 years since this ban, they are still significantly higher than the urban background levels. Gaining knowledge of the source of lead (Pb) in these urban settings will help government to develop better strategies for the abatement of emissions. This work will outline the development and validation of an ICP-MS/MS method for Pb isotope ratio measurements. The ratios between 204 Pb, 206 Pb, 207 Pb and 208 Pb have been studied and different instrument parameters, including the detector settings and interferences removal modes, optimised to ensure measurements of sufficient precision to draw useful conclusions. By comparing ambient particulate samples from a wide range of rural and urban locations throughout the UK with one another and the emission values from the literature, we have been able to make progress towards attributing ambient Pb pollution to specific sources.

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Evaluation of pollution load on contaminated land in north east england using an unmanned aerial vehicle with a multispectral image camera John Dean, Ibrahim Salaudeen, Edmond Sanganyado, Catherine E. Nicholson, Justin J. Perry Northumbria University, UK There has been great concern about the continuous surge in the level of hazardous contaminants being introduced into the environment consciously or unconsciously, mostly through anthropogenic activities. For example, heavy metal accumulations in soil from anthropogenic sources with subsequent consequences constitute a major global environmental problem. However, industrial revolution, urbanization, large-scale agricultural practices and consistent growth in human population constitute major drivers of environmental issues; this has resulted in devastation to the soil environment, with run-off leading to low-quality water due to the effects of pollution by toxic, persistent, and bio-accumulative contaminants, such as, heavy metals (e.g. Pb) 1 , organic contaminants (pesticides, petroleum hydrocarbons and PAHs) and other important emerging pollutants. Furthermore, in other to set quality standards and identify the hazards to human health, food safety and the environment, it is required to describe the sources and the levels of heavy metals in environmental media including the soil because environmental pollution caused by heavy metals is persistent, covert, and long-term. This project will investigate the pollution status of two sites in NE England, one a current ‘live’ industrial complex and the other, the site of a redundant coal mine (and now a country park) using a combination of remote sensing techniques (UAV) and laboratory-based analytical techniques to assess the contaminant load within the sites. Specifically, these studies will collect multispectral image data and field samples to assess the sites for both heavy metals and organic compounds present in the soil. The analytical techniques to be deployed are energy dispersive X-ray fluorescence (ED-XRF) and gas & liquid chromatography-mass spectrometry (GC- MS, LC-MS), respectively. The research will ascertain if continuous usage of the sites potentially poses any ecotoxicological risk on the users, as well as investigate the innovation of using multivariate statistical modelling of multispectral image remote sensing data 2 as an environmental validation tool. References 1. Ma, R. and Dean, J. R. (2022). Health risk assessment of lead in soils from an historic industrial site in North-East England. Separations , 9: 1-11. 2. Ahmed, S., Nicholson, C. E., Muto P., Perry, J. J., and Dean J. R. (2021). Applied aerial spectroscopy: a case study on remote sensing of an ancient and semi-natural woodland. PLOS ONE, 16: 1-19.

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Use of machine learning for monitoring the growth stages of an agricultural crop informed by derived vegetation indices and spatial and temporal soil analyses Shara Ahmed, Nabanita Basu, Catherine E. Nicholson, Simon R. Rutter, John R. Marshall, Justin J. Perry and John R Dean Northumbria University, UK Oats ( Avena sativa L .) is Europe’s fifth largest crop and the sixth most grown cereal worldwide. Further, oat production in the UK reached 825 thousand tonnes in 2022, making it one of the most significant cereal crops grown in the UK. Therefore, to increase the crop yield of oats in response to this high demand, effective crop management strategies are required. Hence, the current study utilised an unmanned aerial vehicle (UAV) with multispectral image sensors to predict winter oats yield by the spectral indices of the normalised difference vegetation index (NDVI) and the chlorophyll index green (CI green) across three different growth stages of the oats crop. In addition, ground truth data relating to the actual crop yield, as well as soil health indicators and crop quality were collected. A hierarchical multinomial logistic regression machine learning model was incorporated to determine if the oats yield could be predicted using the soil health indicators and crop quality. The outcome of the machine learning approach provides a proportional range of soil nutrient levels and crop quality that farmers can use to anticipate the final oat grain yield prior to harvesting. The findings of this research study will be particularly valuable within a Precision Agriculture management strategy to anticipate soil interventions that lead to an enhanced oat crop yield.

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Broadband cavity enhanced UV-VIS absorption spectroscopy for picolitre liquid samples Imogen Fermor-Worth 1,2 and Catalin Chimerel 1 1 Transilvania University of Brasov, Romania, 2 University of Exeter, UK Absorption spectroscopy is a widely used analytical technique due to its label-free nature. However, its application to small liquid samples is hampered by the associated short absorption pathlengths, limiting sensitivity. A concept for the development of an ultrasensitive broadband absorption spectrometer optimised for thin liquid films is presented. We implemented an optical cavity within a fibre-based absorption spectrometer, to enhance sensitivity of the absorbance measurements. In the setup, light propagates multiple times through the sample of interest resulting in greatly increased sensitivity. The bandwidth of the instrument is determined by the choice of two dielectric mirrors forming the optical cavity and, in this implementation, has been set to be optimised for UV detection (250-450 nm). The sensing volume of the spectroscope is prescribed by the choice of optical fibres employed to deliver light to the sample, here we employed 400 µm diameter fibres, giving a sensing volume of 630 picolitres for a thin film of 5 µm in thickness. As a proof-of-concept, we have used our platform for the ultrasensitive detection of the antifungal drug Amphotericin B. Cavity enhancement factors, the equivalent pathlength increase over classical absorption spectroscopy, in the range of 200X have been achieved across a broad wavelength range. Taking advantage of the extended path length the limit of detection for Amphotericin B in a 5 µm thick aqueous film has been dropped from ~125 µg/ml to ~20 µg/ml [1] . We envision multiple applications of our technology ranging from low concentration nucleic acid quantification to label-free cellular drug uptake. References 1. Fermor-Worth, Imogen M., and Catalin Chimerel. "Broadband cavity enhanced UV-VIS absorption spectroscopy for picolitre liquid samples." Analyst (2023).

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