Seminars

Find out about all of the upcoming seminars in the Department of Chemistry.

Dainton Building
Off

Autumn-Winter 2023-24

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

September

Departmental seminar: From Polymer Chemistry to Space Science via Hypervelocity Physics

27 September 13:00
Richard Roberts Auditorium and Blackboard Collaborate

Speaker: Prof Steve Armes
(University of Sheffield)

Contact: Prof Anthony Meijer

Abstract

Cosmic dust is found throughout our Universe and typically travels at hypervelocities (> 1 km/s).
We have spent the past 25 years or so working in close collaboration with several teams of space scientists based in the UK, USA and Germany to gain a better understanding of the behaviour of cosmic dust.
For this talk I will discuss how we design and use microscopic particles that can be coated with an electrically conducting polymer (polypyrrole). This thin overlayer allows the efficient accumulation of surface charge and hence enables the efficient acceleration of such particles up to 10-20 km/s using a high voltage van der Graaf accelerator. These fast-moving particles can be either organic or inorganic in nature and have proved to be useful synthetic mimics for cosmic dust. Space scientists use these particles in laboratory-based experiments to calibrate cosmic dust detectors onboard unmanned spacecraft such as CASSINI and STARDUST. Such studies inform the interpretation of data obtained during such space missions.

October

Departmental Seminar:

11 October 13:00
Richard Roberts Auditorium

Speakers: Dr Julia Sarju
(University of York)

Contact: Dr Natalia Martsinovich

Abstract

Disabled scientists often face considerable barriers and exclusion in laboratory environments. In this talk, I will give an overview of the diversity landscape for disabled scientists (students and staff), amplify lived experiences, and share case studies where disabled scientists are informing and transforming lab environments and cultures for the better!


Departmental Seminar: Bioengineering, burns & cancer – what’s Chem go to do with it?

25 October, 13:00
Richard Roberts Auditorium

Speaker: Dr Sherry Khotari
(Plasma-4, Sheffield)

Contact: Prof Antony Meijer

Abstract

TBA

 

November

Departmental Seminar: Perovskite photovoltaics: ensuring high efficiency and long-term stability for next generation solar cells

8 November 13:00 
Richard Roberts Auditorium

Speaker: Dr Alex Ramadan
(University of Sheffield)

Contact: Prof Julia Weinstein

Abstract

Metal halide perovskites are an exciting emerging semiconductor technology which have been the subject of intense research efforts in the photovoltaic and optoelectronics research community for over a decade. As semiconductors, they are unusual due to their impressive defect tolerance, tunable bandgaps, and excellent optoelectronic properties. These properties have led to unprecedented developments and the power conversion efficiencies of single junction perovskite devices now rival those achievable with crystalline silicon. Now, demonstrating the operational stability of perovskite photovoltaics has become paramount to the successful deployment of this emerging technology.
In this talk I will outline the current state of perovskite photovoltaics and present an overview of the key challenges remaining on the road to commercialisation. I will present some of my work investigating the relationship between the chemistry of these materials, the difficulties faced when trying to study this, and how we currently believe this informs the performance of photovoltaic devices. Finally, I will discuss the operational stability of perovskite photovoltaics and share my opinion on how we can overcome the challenges we face in this area.


Departmental Seminar: Leveraging Technology and Alternative Assessment Approaches to Facilitate Student Learning and Lower Stress in Laboratory Courses: A Choose-Your-Own-Adventure Seminar

10 November 13:00
Dainton LT1

Speaker: Prof Renee Link
(University of California at Irvine)

Contact: Prof Anthony Meijer

Abstract

Laboratory courses have historically been an essential aspect of an education in chemistry. The urgent shift to emergency remote laboratory teaching at the beginning of the COVID-19 pandemic and the subsequent need to support students with little hands-on laboratory experience returning to in-person instruction has caused the chemical education community to rethink our approach to laboratory course pedagogy and assessment.
● In our large organic chemistry laboratory courses for students not focusing their studies on chemistry, we developed choose-your-own adventure online activities using the free, non-linear storytelling software, Twine, to introduce students to choices and the outcomes of their choices in remote labs.
● Upon returning to in-person instruction, we facilitated students’ first hands-on lab experiences by introducing an undergraduate Learning Assistant program as an additional layer of near-peer instruction in the physical laboratory space while also giving the students serving as Learning Assistants an opportunity to strengthen their laboratory skills and knowledge.
● We also created just-in-time technique reminders for use during laboratory sessions as short videos accessible by QR codes attached to relevant equipment.
● To ease the stress around assessment, we have implemented an alternative grading system called specifications grading that removes partial credit but allows students to meet assessment standards by revising and resubmitting work. Marking workloads are kept manageable by providing students with a limited number of virtual tokens that can be exchanged for opportunities such as late passes for work submitted after a due date or resubmissions of work after incorporating feedback on a previous attempt.
● We have also removed the stress of timed practical exams by having students record videos of themself completing techniques in the lab and submitting annotated versions of their work.
● Finally, we are working toward providing a teaching laboratory experience that more closely mimics the process of science by adopting Argument Driven Inquiry (ADI), in which students first learn a fundamental skill in a traditional, expository lab experiment. Then they use the knowledge gained to make procedural choices and collect data to answer an original investigation question. Students work in teams to create mini-posters and engage in an argumentation session with peer teams to refine their claims using their collected data as evidence.
As these varied improvements to our laboratory curriculum cannot possibly be discussed in a single talk, the audience will get to choose which of the innovative approaches they wish to hear more about.


Departmental Seminar: Photoactive Triazolyl Coordination Complexes: from Photochemistry to Sustainable Luminescent Materials

15 November 13:00
Richard Roberts Auditorium

Speaker: Dr Paul Scattergood
(University of Huddersfield)

Contact: Prof Julia Weinstein

Abstract

Photoactive transition metal coordination complexes have been extensively explored over the last few decades, finding uses in applications ranging from new light-emitting technologies to cellular imaging agents and solar cell devices. However, commonly employed metals such as Ru(II), Ir(III) and Pt(II) are not only expensive but are amongst some of the rarest elements found on Earth. Consequently, there is a clear and present need to develop new, sustainable molecules based upon inexpensive and Earth-abundant transition metal elements for light-driven applications. This talk will describe key steps on our journey away from photo-reactive complexes of precious metal elements to the development of new Cr(III) coordination chemistry and the investigation of photoactive complexes based upon this Earth-abundant element. The talk will showcase our most recent work in achieving efficient luminescence within the near infra-red region and describe our work to elucidate the fundamental excited state photophysical properties of these Cr(III)-centred molecules. The talk will conclude with a summary of work currently underway within our laboratory to further develop these systems as efficient luminophores, DNA-binding agents, and photocatalysts.


Departmental Seminar: Sustainable Methodologies for Synthesis

22 November 13:00
Richard Roberts Auditorium

Speaker: Dr Louis Morrill
(University of Cardiff)

Contact: Dr Ben Partridge

Abstract

TBA


Biophysica and photophysical / Chemical Biology Cluster Seminar: Challenges in Discovering Drugs that target Intrinsically Disordered Proteins

29 November 13:00
Richard Roberts Auditorium

Speaker: Dr Rahul Mishra
(Astrazeneca)

Contact: Dr Barbara Ciani

Abstract

ntrinsically Disordered proteins (IDPs) are proteins without any defined tertiary structures under physiological conditions. As IDPs are known to play a critical role in various biological functions and have relevance in various diseases, they are attractive therapeutic targets. However, because of their dynamic nature and complex interactions, application of conventional structure-based drug design methodology remains challenging. Targeting IDPs provides a great opportunity for the novel drug discovery space. Here, in this talk, I will summarize some of the past developments towards the drug design strategies and their successful implementation in targeting IDPs and possible solutions for the future drug development.

December

Departmental Seminar: Biocompatible Artificial Molecular Machines through Dynamic Covalent Chemistry

6 December 13:00
Richard Roberts Auditorium

Speaker: Dr Fredrik Schauffelberger
(KTH Stockholm)

Contact: Prof Anthony Meijer

Abstract

Nature employs molecular machines for almost every biological task, and uses nanoscale molecular movements to recognise, construct and transport biomolecules in extremely precise fashion. Inspired by this biological machinery, we use artificial molecular machines to address topical challenges in biomedicine.[1] By harnessing the same design concepts as biology itself, our group aims to create novel biosensors and therapeutics that are directly interfaced with molecular machines. In particular, artificial molecular machines based on mechanically interlocked molecules (MIMs) have huge potential in modern biomedicine as for example biosensors and drug delivery systems.[2] However, making and operating MIM-based machinery in biological environments is a huge challenge, since most weak interactions used for conformational control are disturbed by the aqueous environment and high concentration of biomolecules. Here, I will show how dynamic covalent chemistry is a useful way to control molecular movement of interlocked molecules in water.[3] We use dynamic covalent bonds both to control co-conformation in molecular shuttles as well as to introduce mechanical bonds around bioderived molecules[4]. These new methodologies can hopefully be used to make and operate novel biocompatible molecular machines with advanced therapeutic or diagnostic functions.

[1] Erbas-Cakmak et al. Chem. Rev. 2015, 115, 10081-10206. [2] Beeren et al. Chem, 2023, 9, 1378-1412. [3] Yu et al. Eur. J. Org. Chem. 2022, e202201130 [4] Yu et al. ChemRxiv, 2023, 10.26434/chemrxiv-2023-v95p8.

Departmental Seminar: Shining light on chemical and biophysical dynamics—from the bulk to single particle, from fs to μs

13 December 13:00
Richard Roberts Auditorium

Speaker: Dr Joe Beckwith
(University of Cambridge)

Contact: Prof Julia Weinstein

Abstract

All of chemical reactivity can, arguably, be encapsulated in two questions: how are molecules oriented and moving, and how are electrons moving? If we answer these questions with high spatiotemporal resolution, then we can understand any chemical reaction occurring in an observed volume. Such a technique that answers this question at single molecule and single particle sensitivity remains out of reach, but I will present two investigations aimed at answering these questions. First, an investigation into how solvent can affect charge transfer, which we studied using bulk solution-phase transient electronic spectroscopy. Second, an investigation in which we show an experiment that measures a single particle's 3D translation with a time resolution of 10 μs and a spatial resolution of ~10 nm in all 3 directions, and measures 3D orientation with 250 μs time resolution. This investigation also naturally opens up investigation into biophysical phenomena, which occur in complex environments on similar timescales. We will close with a vision of future work to enable the spectroscopic interrogation of any non-fluorescent single molecule or nanoparticle as it freely moves in solution.

Spring-Summer 2023-24

January

RSC "2023 Analytical Science mid-career Prize": Sensing the Gut: Monitoring mucosal signalling molecules

19 January 13:00 Dainton Building LT1
 

Speaker: Prof Bhavik Patel
(University of Brighton)

Contact: Prof Nick Turner

Abstract

The bowel has vital functions in the human body, of which one of core functions is to store and expel waste. Therefore, the intestinal tract deals with harsh environments that often make them subjective to acute and chronic inflammation. The bowel is subjective to long-term chronic inflammatory conditions such as ulcerative colitis and Crohn’s Disease. The mucosa epithelium acts as a barrier to toxins and waste, but also plays a critical role in communication to the underlying muscles to direct them to store and expel the waste. This process is governed by signalling molecules serotonin and melatonin. Our research has focused on the development of novel electrochemical sensing devices that allow the means monitor the real time release of serotonin and melatonin from single villi to the entire colon. Our studies have allowed the means to understand the regulation of the EC cell and important understand how this alters with disease. The relationship, interplay, and impact of chronic inflammation and the signalling molecules within the bowel is a complex story which will be explored within this presentation. 


Departmental Seminar: Action spectroscopy of gas-phase ions

31 January 13:00
Richard Roberts Auditorium

Speaker: Dr James Bull
(University of East Anglia)

Contact: Dr Simon King

Abstract

Action spectroscopy, usually performed in the gas phase, encompasses a range of spectroscopic techniques that monitor the ‘actions’ of molecules resulting from the absorption of light. Potential actions include ejection of an electron (e.g. photoelectron and photodetachment spectroscopy), fragmentation of the molecule (photodissociation spectroscopy), and isomerisation or changes in molecular shape (photoisomerisation spectroscopy). Our laboratory seeks to develop new action spectroscopy instrumentation and techniques, based on measuring several actions, and apply these methods to investigate fundamental processes and properties, including: (1) understanding the structure and function of photoactive biological chromophores, (2) high-precision molecular structure and property determination, and (3) probing the photochemistry of atmospherically and astrochemically relevant molecules.

The first part of this talk will introduce the technique of photoisomerisation action spectroscopy, which employs elements of ion mobility spectrometry and electronic spectroscopy to prepare and study isomer-selected ions (such reactant selectivity is rarely achievable in solution-based studies) and to probe isomerizations directly. When coupled with other action spectroscopy techniques, including photoelectron, photodetachment, and their femtosecond time-resolved variants, we can obtain unparalleled insight into the detailed excited state dynamics, for example measuring isomeric product distributions, internal conversion routes, and competitive dynamical timescales, and fingerprinting the presence of barriers in excited-state reactions. The second part of the talk will focus on astrochemistry-related studies performed in a cryogenic cooling (T ≈ 13 K) environment under ultrahigh vacuum (P ≈10-14 mbar), providing ‘molecular cloud in a box’ conditions. Experiments on target species, including carbon cluster anions and cations of naphthalene, azulene, cyanonaphthalene and indenyl, provide characterisation of heat- and light-induced cooling dynamics over the ultraslow timescale (millisecond to seconds). The measured dynamics include monitoring the competitions between statistical dissociation, recurrent fluorescence, and infrared (vibrational) cooling. Understanding the dynamical interplay of these cooling processes is central to predicting molecular stability and, in turn, abundance of these molecules in space.

February

Departmental Seminar: Biomimetic engineering: innovations inspired by nature.

7 February 13:00
Dainton Building LT1

Speaker: Dr Marloes Peeters
(University of Manchester)

Contact: Prof Nick Turner

Abstract

Molecularly imprinted polymers (MIPs), porous materials containing high-affinity binding sites for the analyte of interest, can rival natural recognition elements in terms of affinity but are cost-effective and possess superior thermal and chemical stability. We have incorporated MIPs as synthetic receptors into sensors used for a range of applications in challenging diagnostic media, such as food extracts and nose and throat swabs, as these materials are more robust compared to antibodies that denature under the influence of pH and temperature. The MIPs were electrografted onto screen-printed electrodes (SPEs), carbon electrodes that are highly reproducible and enable disposable use due to their low-cost. These MIP-functionalised SPEs were then embedded into a home-made thermal device that facilitated detection in the low nanomolar range for a range of bioanalytes. This thermal technique, coined the Heat-Transfer Method, measures target concentration via monitoring the heat-transfer resistance at the solid-liquid interface; binding of targets to the cavities of the MIP has shown to lead to an increase in both the electrical and thermal resistance. However, this portable device still requires the use of a laptop equipped with LabView software to run and the thermocouples that are used are bulky and costly. Thus, we have developed a novel thermo-electric technique that uses thermistors instead; thermistors offer better resolution, can be miniaturised, and can serve as disposable materials. In this presentation, I will showcase how my group will use this method for early diagnosis of heart attacks via measuring of biomarker concentrations in serum. Moreover, I will show the dual functionality of MIPs can be exploited for them to be used as drug nanocarriers and improve chemotherapeutic treatment.


Departmental Seminar: Light and Metal Chromophores: Ultrafast Photochemistry, Bioimaging, and Photocatalysis

14 February 13:00
Richard Roberts Auditorium

Speaker: Prof Julia Weinstein
(University of Sheffield)

Contact: Prof Anthony Meijer

Abstract

Light absorption by molecules and materials initiates a plethora of reactions on the ultrafast timescale. A particularly exciting process is photoinduced electron transfer, which is the primary step in photosynthesis and many applications related to photocatalysis, PDT, or antibacterial water treatment.  We combine light with light-absorbing molecules – transition metal complexes – to work in a number of directions:

Our methods: Ultrafast photochemical reactions involve electronic, structural, and spin dynamics of many excited states. To understand those entangled processes, we use a combination of femtosecond optical laser spectroscopies – for example, electronic transient absorption, time-resolved infrared and 2DIR, fluorescence upconversion, and resonance Raman spectroscopies. Recent exciting development of femtosecond X-ray free electron lasers opened up the way to follow structural changes in molecules in their excited state directly, using X-ray equivalents of optical spectroscopies – X-ray absorption, emission, or scattering – which literally allows one to make a “molecular movie” to watch chemistry happen.


Departmental Seminar: Radiopharmaceutical development: the journey from new radiolabelling technologies to multi-isotope nuclear imaging 

21 February 13:00
Richard Roberts Auditorium

Speaker: Prof Steve Archibald
(Kings College London)

Contact: Prof Jim Thomas

Abstract

The development of theranostic radiopharmaceuticals, particularly for applications in oncology, is a rapidly expanding field with continued commercial growth predicted over the next decade. However, challenging radiochemistry is often required in the manufacture of radiopharmaceuticals, creating a roadblock to the widespread accessibility of theranostics. Results will be presented on microreactor technologies, supramolecular radiochemistry, theranostic radiopharmaceutical design and in vivo multi-radiotracer imaging protocols that offer potential solutions to these challenges.

(1) Microfluidics offer a route into efficient dose-on-demand production of radiopharmaceuticals. Efficient processes and simplified reactor design generate opportunities for either fluorination reactions or high molar activity labelling with radiometals. We have focussed on novel design of key components of these reactors to offer high yielding chemical syntheses that are compatibility with the small scale reactions typical of radiopharmaceutical production.

(2) Significant interest has emerged in the use of supramolecular constructs for nuclear imaging. The CageTag platform that we have developed with Paul Lusby (Edinburgh) is a reagentless, rapid and simple method that could allow the development of “off-the-shelf” theranostic kits. It relies on self-assembling, kinetically robust CoIII4L6 tetrahedral cages, that can be easily and rapidly radiolabelled through non-covalent encapsulation of a radioisotope.

(3) Due to its involvement in cell trafficking and over-expression in several types of cancer, imaging of CXCR4 chemokine receptor (along with ACKR3) expression levels in cancers has potential as a prognostic marker or for informing treatment selection. We have targeted CXCR4 using a novel configurationally restricted azamacrocyclic transition metal complexes with nanomolar receptor affinity and long receptor residence times, using the theranostic isotope pair of copper-64 and copper-67.

(4) The in vivo imaging of multiple isotopes simultaneously is relevant to combination therapies and stability profiling in radiotracer validation. Logistical constraints around isotope supply and radiotracer production have stymied this development. Improved isotope availability and the need for simultaneous assessment of multiple biological targets requires novel multiple isotope imaging protocols. We have validated a triple isotope protocol that shows simultaneous imaging from a single injection in preclinical animal models.

March

Departmental Seminar: Exploring molecular design in the age of automation and ML

6 March 13:00
Richard Roberts Auditorium

Speaker: Dr Fernanda Duarte
(University of Oxford)

Contact: Prof Nick Williams

Abstract

The accurate modelling of chemical transformations stands as a significant challenge in computational chemistry, limiting molecular design. Conventional approaches to characterizing reactivity and selectivity while routine, remain time-consuming and non-systematic, hindering progress as systems grow in complexity and demand the exploration of numerous potential reaction pathways simultaneously. In this talk, I will present our team’s efforts to tackle these challenges by integrating molecular modelling, automation, and machine learning methods. Our goal is to develop computational tools that enable the exploration of novel molecules and their synthetic routes. 

I will showcase our work on automating the exploration of reaction mechanisms using our open-source tool autodE, designed to reduce technical barriers while increasing efficiency and accuracy. Highlighting its broad applicability and current challenges. Additionally, moving towards increasingly complex systems, I will discuss our efforts in modelling reactions in solutions using machine learning potentials (MLPs) as efficient surrogates for traditional ab initio methods. Our methodology facilitates the generation of data-efficient training sets that sufficiently sample the conformational spaces and achieve high accuracy in complex systems. Finally, in scenarios where mechanistic exploration is impossible and data availability is limited, we demonstrate the efficacy of combining available datasets and chemistry knowledge to develop predictive models that facilitate property prediction and the exploration of new molecular scaffolds.​​


Departmental Seminar: Protein-nucleic acid interactions in Plasmodium apicoplast

13 March 13:00
Richard Roberts Auditorium

 

Speaker: Dr Indrajit Lahiri
(University of Sheffield)

Contact: Prof David Williams

Abstract

Protein-nucleic acid interactions are central to several essential cellular processes, including all the steps of the central dogma. Unsurprisingly, these interactions are key to understanding thepathology of several life-threatening diseases and finding potential cures for them. We are interested to use structural and biochemical approaches to decipher how protein-nucleic acid interactions enable essential biological reactions. I will discuss our research program at the University of Sheffield geared towards understanding the molecular mechanisms of organellar nucleic acid transactions in human pathogens. Our current focus is directed towards Plasmodium, the pathogen responsible for causing malaria. Although many anti-malarial drugs exist, drug-resistant Plasmodium strains are on the rise, underscoring the need to have a better understanding of the Plasmodium-specific processes. We are interested in a unique non-photosynthetic plastid harboured by this pathogen called the apicoplast. Apicoplasts maintain their own genome with the help of dedicated bio-machinery. The essential nature of these nano-machines makes them potential drug targets. However, a dearth of mechanistic insight into the apicoplast-specific nucleic acid processes has been a major hindrance. I will talk about how we plan to use cryo-EM in conjunction with kinetic and smFRET approaches to look at apicoplast replication and genome organisation.


Departmental Seminar: TBA

20 March 13:00
Richard Roberts Auditorium

Speaker: Prof Duncan Browne
(University College London)

Contact: Prof Joe Harrity

Abstract

TBA

April

Departmental Seminar: TBA

17 April 13:00
Richard Roberts Auditorium

Speaker: TBA

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May

Departmental Seminar: TBA

1 May 13:00
 

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Departmental Seminar: TBA

8 May 13:00
 

Speaker: TBA

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Departmental Seminar: TBA

 22 May 13:00
 

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Departmental Seminar: TBA

29 May 13:00
 

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June

2022 Faraday Division early career award (Marlow Award): TBA

5 June 13:00 Dainton Building LT1

Speaker: Dr Basile Courchod
(University of Bristol)

Contact: Dr Grant Hill

Speaker: TBA

Contact: 

Abstract

TBA

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