Chemistry seminars

Autumn-Winter 2024-25

Departmental Seminars are generally held on Wednesdays. Please always check the time as it might change for some speakers.

October

Departmental Seminar: The Changing Shape of DNA in Genes

2 October 12:00 DB-LT01

Speakers: Prof Zoe Waller
(University College London)

Contact: Prof Jim Thomas

Abstract

DNA is not always a double helix. Cytosine-rich DNA sequences are able to form i-motifs, four-stranded structures comprised of parallel-stranded DNA duplexes connected in an anti-parallel orientation by intercalated, cytosine–cytosine base pairs. i-Motifs are stabilised by acidic conditions, which promote C-C base pairing via hemi-protonation of the N3; folding is rapid and this property has been utilised in many different nanotechnological applications. It is often assumed that i-motif formation is dependent on low pH, but there have always been examples where they are still present under neutral conditions. i-Motif can form at neutral pH depending on the types of sequence, cations and the presence of ligands. i-Motif structures have been shown to form in cells and stabilisation of i-motif structures has been found to destabilise G-quadruplex DNA structures in cells, disrupt the action of the enzyme telomerase, inhibit DNA polymerase and enhance gene expression.

Here I describe recent work from our group towards understanding the relationship between GC-rich sequences in the human genome, the different structures they can form and their different biological functions.

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Departmental Seminar: Sustainable bio-sourced coatings for the food sector - preservation and sensing of food quality 

9 October 12:00 DB-LT01

Speaker: Dr Chester Blackburn
(University of Sheffield)

Contact: Prof Nick Turner

Abstract

The dairy industry in the UK is estimated to be worth around £8-9 Bn to the UK economy. However, at least a third of food production globally is estimated to be wasted, a driving force behind climate change. Dairy products are understood to retain quality and be fit for consumption past their “Best before” date, as the date is largely an indication of quality rather than safety; therefore, the consumer is encouraged to use sensory tests (smell, appearance etc.) to make a judgement on the quality of the food. However, as not all consumers are comfortable making this assessment, and given it is a subjective judgement, there is a significant amount of dairy produce food waste that otherwise could be consumed.

This talk will focus on an idea being proposed for a UKRI (FLF) Fellowship application. I will discuss my prior and current research experience. Proposing, the use of multi-functional sustainably sourced biopolymers and small molecules for incorporation into food packaging to function as both an anti-fouling layer and quality guide of dairy products, namely soft cheese and milk. 

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 Departmental Seminar: 2D Framework Materials for Energy Applications and Molecular Separations

16 October 12:00 DB-LT-01

Speaker: Prof Andreas Schneeman
(Technische Universität Dresden)

Contact: Dr Jona Foster

Abstract

Framework materials like metal-organic frameworks or covalent organic frameworks (COFs) are porous, crystalline materials constructed from molecular building blocks. In COFs, the building blocks are connected via covalent bonds, forming robust networks. If they are flat, highly symmetric molecules, two dimensional frameworks can be constructed, which are stacked in the third dimension by weak interactions for instance hydrogen bonds or π-π interactions. By functionalization of the framework backbone with aliphatic side chains the stacking is weakened and their surface properties drastically change, making them hydrophobic. This can be leveraged for instance in pyrene-based COFs, which can be exfoliated from organic solvents into nanosheets with average thicknesses below 1.5 nm, which were integrated into separator membranes for lithium-ion batteries. This concept was transferred to electrocatalytically active metalloporphyrin COFs and the inclusion of side chains improved their stability in alkaline media, increasing their stability during the oxygen evolution reaction and lowering the overpotential compared to non-functionalized analogues. Furthermore, the stacking-offset between adjacent layers in metalloporphyrin COFs can be adjusted by the type of attached side chain, as well as the degree of metalation.
Stacking-offsets can also be leveraged for molecular separations. Introduction of alkyne bridges into a pyrene-based 2D COF induced a shift between neighbouring layers, which created electron-rich pockets. These pockets are used for static bromine adsorption from the gas phase, as well as for the selective uptake of Br 2 from mixed Br 2 /I 2 solutions. Hydrophobization of the framework backbone can not only be achieved by installation of aliphatic side chains, but also by substituting aromatic linkers with saturated molecules. With this strategy, a cyclohexane-bridged COF was prepared, which featured an increased affinity towards the adsorption of saturated hydrocarbons, showing high adsorption selectivity towards ethane over ethylene.

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 Departmental Seminar: TBA

23 October, 12:00 DB-LT01

Speaker: Dr Alex Cresswell
(University of Bath)

Contact: Dr Ben Partridge

Abstract

Alex's research combines photochemistry with organic synthesis. More specifically has explored combining visible light photocatalysis and Hydrogen Atom Transfer catalysis to generate unprotected alpha-amino radicals from primary amines. These nucleophilic radicals can then be trapped with electrophiles such as alkenes to generate complex C-tertiary amine products. His group has applied this approach to synthesise a range of interesting, medicinal-chemistry relevant chemicals.

November

Departmental Seminar: Developing Automated Experimentation for Delivering the next generation of Polymer Materials

6 November 12:00 DB-LT01

Speaker: Prof Nick Warren
(University of Sheffield)

Contact: Prof Steve Armes

Abstract

Applying enabling technologies such as automation and artificial intelligence (AI) in materials science is one of the only options when it comes to meeting the need for the next-generation materials required to sustain society. Despite considerable uptake of emerging technologies in small-molecule chemical synthesis, it is still yet to become commonplace within polymer science and there is little sign of a significant shift away from traditional ‘flask based’ techniques. By making advances in reactor design, online monitoring and automation our research explores technologies which have the potential to accelerate discovery and development of chemical products including but not limited to polymers. This talk outlines our progress to date, which focusses on the development and implementation of automated reactors equipped with online monitoring and computational intelligence. It is demonstrated that these platforms are capable of autonomously exploring reaction parameter space with minimal human interaction. This includes the ability to conduct automated kinetic screens or for AI-driven multi-objective self-optimisation of polymerization conditions. As a result, reaction optima and trade-offs inherent with the process can be autonomously identified. It is demonstrated that optimum reagents and conditions for the polymerisation of several monomers can be determined with no human interaction and minimal prior knowledge of the chemistry. By expanding reactor capability and augmentation of chemical models, we show that it is possible to further reduce the need for physical experimentation, which has significant implications with respect to efficiency and sustainability.

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Departmental Seminar: Nanoscale dynamics and organisation at solid-liquid interfaces: from single molecules to correlative group effects

13 November 12:00 ADB-LT02

Speaker: Prof Kislon Voïtchovsky

Contact: Prof Nadav Amdursky

Abstract

Liquid molecules behave differently at the surface of immersed solids compared to bulk liquid. This ‘interfacial liquid’ can control nanoscale processes, from molecular self-assembly to local electrostatics, molecular transfer and lubrication. In soft matter and in biosystems, the effect is further enhanced by the interfacial liquid’s ability tune the structure and properties of the solid, from the shaping of dissolved polymer molecules to the mechanics of living cells. 

Using bespoke experimental approaches based atomic force microscopy, it is possible to map the equilibrium organisation and local diffusion dynamics at solid-liquid interfaces with nanoscale precision. The results, complemented by computer simulations, show an interplay between local molecular organisation and the emergence of mesoscale phenomena over hundreds of nanometres though group effect. In bio-membranes, for example, water-stabilised ionic condensates can remain in place for tens of seconds, dramatically altering the local electrostatics and mechanical properties with consequences for the membrane shape. We also track the mobility of interfacial water and of the molecules within fluid membranes and show how correlated motion can control self-assembly. 

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Departmental Seminar: A journey through responsive systems that interact with light – from DNA to Dyes 

20 November 12:00 DB-LT01

Speaker: Dr Denis Hartman
(University of York)

Contact: Dr David Williams

Abstract

Light-matter interactions are crucial in the development of new technologies and currently find use in all areas of chemistry, from light-responsive systems in biology to modern optoelectronic devices. One area that this finds use in is in the remote control of biological function. I have developed photoresponsive systems that are able to control transcription and translation with light through modification of DNA. Due to the orthogonality of the photocages, simple logic gates could also be constructed and this was implemented in synthetic cells. Another area of interest is in chiroptical materials, which can find use as sensors, emitters and spintronic devices. Here, I have developed chiral switching supramolecular architectures based on perylene diimide dyes. These systems allowed for switching of chiroptical properties with external inputs, such as solvent or guest species, as well as state of matter.
In the talk I will be embarking on a journey through several ways that we can harness light, show some subtleties in the chemistry that governs this, and display the exciting potential that arises from the utilisation of such systems in a variety of contexts.

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Departmental Seminar: Ligand Design in Molecular Materials Chemistry

27 November 12:00 DB-LT01

Speaker: Dr David Herbert
(University of Manitoba)

Contact: Prof Julia Weinstein

Abstract

Abstract: The C=N bond is a critical structural piece of many N-donor ligand scaffolds and is central to the properties and reactivity of a number of important coordination complexes - for example, promoting charge transfer character in complexes of bipyridines (e.g., [Ru(bpy) 3 ] 2+) or the "redox non-innocence” of alpha-diimine complexes. Benzannulation can extend the conjugated C=N containing π-system of pyridine to quinoline (2,3-benzopyridine) to acridine (2,3-benzoquinoline), stabilizing the lowest unoccupied molecular orbital (LUMO) of the molecule and boosting electron-accepting properties, but the positioning of the benzannulation matters. For example, phenanthridine (3,4-benzoquinoline), an asymmetric isomer of acridine, bears a similarly electronically accessible extended π-system but more chemically isolated imine-like C=N moiety. In this presentation, the impact of such site-selective π-extension on the chemistry and properties of phenanthridine as a molecule and ligand will be discussed.

December

Departmental Seminar: Electrophilic borylation and alumination for the functionalisation of sp² and sp³ C-H bonds

4 December 12:00 DB-LT01

Speaker: Prof Michael Ingleson
(University of Edinburgh)

Contact: Dr Rob Dawson

Abstract

C-H borylation provides efficient access to organoboranes that are ubiquitous synthetic intermediates (e.g. in Suzuki-Miyaura couplings and beyond) and are also increasingly important functional molecules in their own right. Examples of the latter include boron-doped polycyclic-aromatic hydrocarbons as emissive materials and organoborane based bioactives (including for tackling antibiotic resistance – e.g., Xeruborbactam). Our group has an ongoing interest in developing inter- and intra-molecular C-H borylation reactions using boron Lewis acids in what is a Boron analogue of the Friedel-Crafts reaction. This can use simple boranes, e.g., BCl₃ and BBr₃, or for more challenging conversions bespoke boron cations. This talk will cover a selection from our recent work on using boron electrophiles in directed C-H borylation, specifically in O-directed borylation e.g., to make useful intermediates for accessing bioactives (e.g. A) and in borylation directed borylation for functionalising sp² C-H (e.g. to form B) and sp³ C-H (e.g. to form C) bonds. The latter involves an unusual sp³ C-H alumination.

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Departmental Seminar: TBA

11 December 12:00 DB-LT01

Speaker: Dr Geraint Morgan
(Open University)

Contact: Prof Nick Turner

Abstract

TBA

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Departmental Seminar: Single-Protein Electronics: from Molecular to BioMolecular Electronic

18 December 12:00 DB-LT01

Speaker: Prof Ismael Diez Perez

Contact: Prof Nadav Amdursky

Abstract

In this seminar, I will present our latest efforts on understanding and control charge transport in a single-protein junction, with an emphasis on how to harness enzymatic activity electrically in an individual enzyme. Our approach relies on trapping individual redox proteins in an electrochemically controlled tunneling junction to characterize their main electrical signatures. The method can capture very fine details of the charge transport mechanisms across proteins in an aqueous environment.
I will first introduce the methodology with a couple of examples of electrochemically controlled single-molecule wires with synthetic backbones, then introduce our studies on a benchmark redox protein model such as a bacterial blue Cu-Azurin. We will show first the main observed electrical signatures of these systems that make them particularly efficient in transporting charge. We then bioengineer the outer protein surface using point-site mutagenesis as a mean to get a more detailed picture of possible electron pathways through the protein backbone.
Finally, I will switch to our very recent charge transport studies on redox enzymes. Using the above electrochemically controlled single-protein methodologies, we demonstrate that when an individual redox enzyme is trapped on a nanoscale junction, a distinct telegraphic noise can be directly correlated to the enzymatic activity of the enzyme during the active bioelectrocatalytic conditions. The last study opens a new door for the fundamental studies of redox enzymatic catalysis and brings prospects to the high-resolution electrical detection of an enzymatic reactions.

Spring-Summer 2024-25

January

Departmental Seminar: Fourier transform voltammetry: what, why and how

22 January 12:00 DB-LT01

Speaker: Prof Alison Parkin
(University of York)

Contact: Dr Jim Reid

Abstract

The Parkin group are interested in the mechanisms of biological electron transfer, and how electrochemistry can be utilised to probe this chemistry, seeking to answer questions about enzyme structure and function and understand the evolutionary pressures that have led to certain proteins being selected over others. The requirement for a highly sensitive voltammetry technique led us to collaborate with Prof Alan Bond (Monash) to start integrating Fourier transform voltammetry into the protein film electrochemistry toolkit. This talk will describe the progress we have made in developing Fourier transform methods, what we have learnt about photosynthetic electron transfer proteins, how we are improving our theoretical understanding of our results, and why and how making such measurements can also be useful in sensing applications such as in whiskey testing.

February

Departmental Seminar: Down to Earth: From Sniffing Comets and Mars to Submarines, Whisky, Cars, Cancer and more…

5 February 12:00 DB-LT01

Speaker: Dr Geraint Morgan
(Open University)

Contact: Prof Nick Turner

Abstract

Dr Morgan will take you on a journey around the solar system, that is thirty years in the making – covering his career developing analytical instrumentation for the Rosetta and Beagle2 missions to the more recent application of the collective know-how to solve problems back here on Earth. This has included developing an award winning multi-disciplinary team to support the primary strategic defence capability of the UK, as well as providing solutions for academic and commercial partners. Partnerships with commercial instrument manufacturers has resulted the development of a range of novel non-targeted assays, using comprehensive gas chromatography-mass spectrometry (GCxGC-MS) and its associated machine learning classification software, to provide customers within novel insights into their complex samples – enabling improvements in their processes or mitigation of issues. Having led the knowledge exchange agenda at the OU, as well as being the director of several start-up companies, he will provide feedback on the lessons he has learnt along the way and his experiences of all the different knowledge transfer mechanisms available to academics, within and outside of the university, and their potential benefits.

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Departmental Seminar: Rational routes to porous carbons for sustainable energy applications

12 February 12:00 DB-LT01

Speaker: Prof Robert Mokaya
(University of Sheffield)

Contact: Dr Rob Dawson

Abstract

The talk will explore the conversion of biomass and other waste carbonaceous matter to porous carbons with optimised properties for use in energy storage applications, and specifically the storage of CO2, H2 or methane. The talk will describe how study of a wide range of biomass and non-biomass precursors has enabled the predictable and targeted preparation of porous carbons with optimised properties for such sustainable energy applications.

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Departmental Seminar: Your Chemistry has got Potential: Highly reactive intermediates without the “bang”

19 February 12:00 DB-LT01

Speaker: Prof Kevin Lam
(University of Greenwich)

Contact: 

Abstract

Chemistry thrives on highly reactive intermediates - remarkable tools for building complex molecules. But one might ask: shouldn't their synthesis involve fewer risks than a special life insurance policy? Synthetic organic electrochemistry, which has its roots in the pioneering work of Faraday and Kolbe on the electrolysis of aliphatic carboxylic acids, has become a powerful tool for sustainable chemical synthesis. Despite numerous successful industrial applications, its wider potential remains under-exploited. However, the increasing demand for greener, safer and more cost-effective synthetic methods has spurred the development of innovative electrosynthetic techniques. In this talk, we will review novel, safe, green and economically viable electrosynthetic methods for the preparation of highly reactive organic intermediates, including iso(thio)cyanates, isocyanides, carbocations and diazo compounds. These methods significantly reduce the inherent risks associated with traditional synthetic approaches, while improving efficiency and sustainability. We will also highlight the scalability of these processes through flow electrosynthesis and their impactful real-world applications within the pharmaceutical industry, with case studies in collaboration with GSK, AstraZeneca and Johnson & Johnson.

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RSC 2024 Corday-Morgan Mid-Career Prize for Chemistry: Mapping microscopic viscosity and temperature using molecular rotors

26 February 12:00 DB-LT01

Speaker: Professor Marina Kuimova
(Imperial College)

Contact: 

Abstract

Viscosity is one of the main factors which influence diffusion in condensed media. In a cell viscosity can play a role in several diffusion mediated processes, such as drug delivery, signalling and mass transport. Previously, alterations in viscosity in cells and organs have been linked to malfunction; however, mapping viscosity on a single-cell scale remains a challenge. We have imaged viscosity and crowding inside lipid mono- and bi-layers, in cells and in vivo using fluorescent probes, called molecular rotors. In molecular rotors the speed of rotation about a sterically hindered bond is viscosity-dependent, which strongly affects fluorescence lifetime or spectra of rotors, allowing fluorescence imaging. This approach enabled us to measure both the microscopic viscosity and temperature as well as the presence of unusual DNA topologies, G-quadruplexes, and monitor their temporal changes in real time. The talk will cover our recent developments of this technique, such as genetic and passive targeting of rotors and applications to monitoring disease.

March

Departmental Seminar: Chemical strategies for biomolecule-material conjugation

5 March 12:00 DB-LT01

Speaker: Dr Chris Spicer
(University of York)

Contact: Prof Nadav Amdursky

Abstract

3D biomaterials can be used to scaffold the growth of human cells into in vitro models of tissues, for studying health and disease. A key property of these materials is there ability to provide biochemical signals to the growing cells, to direct and accelerate tissue growth. In this talk, I will talk about our efforts to functionalise biomaterials with the signalling peptides and proteins needed to induce this biochemical signalling, with a focus on the underlying chemistries we are developing to site-selectively modify native proteins, and to mediate late-stage modification of peptides.

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RSC Corday-Morgan Prize: Chemical CryoBiology. Molecular strategies to deliver frozen biologics

12 March 12:00 DB-LT01

Speaker: Prof Matt Gibson
(University of Manchester)

Contact: 

Abstract

The cold chain is essential to deliver therapeutics intact to patients: From frozen stem cells for leukaemia treatment to emerging mRNA vaccines (e.g. COVID-19). Cryoprotectants are essential to ensure they survive the passage from ambient to frozen, and back again. We are developing small molecules and polymers which can mitigate cold stress to allow ‘the unfreezable to be frozen’ and to reduce or replace the current organic-solvent based cryoprotectants. In this talk I will highlight our approach which spans the discovery of polymers and nanomaterials which can bind ice crystals, or even induce the formation (nucleate) of new ice crystals and recent work on site-selective bio-conjugation of cryoprotecting polymers to proteins. I will also show how we are cryopreserving complex 3D cell-based models with the aim of reducing animal testing.

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RSC Tilden Prize: TBA

19 March 12:00 DB-LT01

Speaker: Prof Alessandro Troisi
(University of Liverpool)

Contact: 

Abstract

TBA

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Departmental Seminar: TBA

26 March 12:00 DB-LT01

Speaker: Prof Börje Sellergren
(Malmo University)

Contact: 

Abstract

TBA

April

RSC Bourke-Liversidge Prize: TBA

2 April 12:00 DB-LT01

Speaker: Prof Scott Habershon
(University of Warwick)

Contact: 

Abstract

TBA

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Departmental Seminar: TBA

30 April 12:00
TBC

Speaker: Dr Michaela Matta
(King's College London)

Contact: Prof Anthony Meijer

Abstract

TBA

May

Departmental Seminar: TBA

7 May 12:00
TBC

Speaker: 

Contact: 

Abstract

TBA

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Departmental Seminar: TBA

21 May 12:00
TBC

Speaker: 

Contact: 

Abstract

TBA

June

Departmental Seminar: TBA

June 12:00
TBC

Speaker: 

Contact: 

Abstract

TBA