Interactions, Interfaces and Sensing

Research in this section involves measurement, technique and instrument development and computation, with applications right across chemistry and with strong links to biosciences, chemical engineering, computer science, materials science, medicine and physics.

We have particular expertise and interests in analytical science; bio-nanotechnology; biophysical chemistry; catalysis; charge transfer and transport; clusters and nanoparticles; electrochemistry; environmental chemistry; fluorescence; magnetic resonance spectroscopy and imaging; optical sensors; scanning probe microscopy; self-assembly; simulation and modelling; single molecule imaging; soft matter; solvation effects; surface and interfacial chemistry; synchrotron-based characterisation; theoretical chemistry.

Research section leader

Areas of interest

Microscopy technique development, single molecule imaging, biophysical chemistry, molecular counting, fluorescent probe development

Representative publication: Live‐Cell Localization Microscopy with a Fluorogenic and Self‐Blinking Tetrazine Probe

P. Werther, K. Yserentant, F. Braun, N. Kaltwasser, C. Popp, M. Baalmann, D.-P. Herten and R. Wombacher
Angew. Chem. Int. Ed. (2020), 59, 804.

Illustration of Live‐Cell Localization Microscopy with a Fluorogenic and Self‐Blinking Tetrazine Probe

In this paper f‐HM‐SiR is presented as a small-molecule-based label with high functionalization allowing for excitation-independent super-resolution imaging with minimal phototoxicity in live-cell experiments. The probe is the first to combine fluorogenicity, photostability, high brightness, self-blinking, bio-orthogonal conjugation and far-red emission in a single label, making it highly favourable for single molecule localization microscopy in live cells. Using this probe greatly improved the imaging quality by reducing unspecific fluorescence (fluorogenicity) while allowing for long time imaging using low excitation powers (self-blinking).

Research section members

Areas of interest

Analytical chemistry; bio-nanotechnology; biophysical chemistry; catalysis; charge transfer and transport; clusters and nanoparticles; electrochemistry; scanning probe microscopy; self-assembly; single molecule imaging; soft matter; surface and interfacial chemistry

Representative publication: Unsupervised vector-based classification of single-molecule charge transport data

Mario Lemmer, Michael S. Inkpen, Katja Kornysheva, Nicholas J. Long & Tim Albrecht
Nature Communications (2016)  Article number: 12922 

In this paper, we outline a new approach to analysing single-molecule charge transport and other data, namely by Multi-Parameter Vector Classification (MPVC). This allows for largely unsupervised classification of large datasets, essentially without making any a priori assumptions of what they look like.

Areas of interest: 

Analytical chemistry; batteries; electrochemistry; magnetic resonance spectroscopy and imaging; simulation and modelling; soft matter

Representative publication: Operando visualisation of battery chemistry in a sodium-ion battery by 23Na magnetic resonance imaging

Joshua M. Bray, Claire L. Doswell, Galina E. Pavlovskaya, Lin Chen, Brij Kishore, Heather Au, Hande Alptekin, Emma Kendrick, Maria-Magdalena Titirici, Thomas Meersmann & Melanie M. Britton
Nature Communications 11 (2020) 2083

Illustration of Operando visualisation of battery chemistry in a sodium-ion battery by 23Na magnetic resonance imaging

Sodium ion batteries (NIBs) offer significant cost and sustainability benefits over current lithium ion batteries, while maintaining high energy densities. Yet, there remain many challenges preventing their commercialisation, which is driving the development of improved SIB electrodes and electrolytes, as well as better understanding of the solid-electrolyte interphase and dendrite formation.  Yet, the search for, and optimisation of, new sodium ion battery materials requires detailed measurement and characterisation, in operando, of each battery component, as well as the interactions and synergies between components and the causes of battery degradation. These detailed observations are currently lacking and inhibiting progress. This paper addresses this deficiency and reports the development of in operando 23Na magnetic resonance imaging (MRI) to enable, for the first time, direct visualisation of battery chemistry in a NIB, an exploration of the synergies between multiple components within the NIB and an assessment of the behaviour of a novel non-graphitic carbon SIB electrode material.  This paper reveals new information about the environment and distribution of sodium within the NIB, which is correlated with the electrochemical behaviour of the cell. We observe, for the first time, the formation of sodium dendrites during galvanostatic plating in a sodium-metal cell and, more surprisingly, metallic sodium species on hard carbon upon first charge (formation) in a full-cell configuration.

Areas of interest

Active colloids; colloidal open crystals; colloidal self-assembly; computation and theory of soft materials; discotic liquid crystals; hierarchical self-assembly; multifunctional materials; photonic band gap materials; rheology of soft matter; topological soft matter

Representative publication: Leveraging Hierarchical Self-Assembly Pathways for Realizing Colloidal Photonic Crystals

Abhishek B. Rao, James Shaw, Andreas Neophytou, Daniel Morphew, Francesco Sciortino, Roy L. Johnston and Dwaipayan Chakrabarti

ACS Nano 14 (2020) 5348-5359

Illustration of Leveraging Hierarchical Self-Assembly Pathways for Realizing Colloidal Photonic Crystals

This computational study demonstrates a novel route to a much sough-after photonic crystal, exploiting hierarchical self-assembly pathways for designer colloidal particles via uniform clusters to promote crystallisation. The versatility of this bottom-up route to yield a variety of colloidal open crystals has been established in a series of recent studies.

Image credit: Wesley Flavell and Andreas Neophytou

Group web page

Ruchi Gupta Group

Areas of interest

Analytical science, optical sensors, microfluidics, micro-/nano-fabrication.

Representative publication: Method for Determining Average Iron Content of Ferritin by Measuring its Optical Dispersion

R. Gupta, N.A. Alamrani, G.M. Greenway, N. Pamme, N.J. Goddard,
Analytical Chemistry, 2019, 91, 7366. DOI: 10.1021/acs.analchem.9b01231.

Illustration showing Method for Determining Average Iron Content of Ferritin by Measuring its Optical Dispersion

We report a method to determine the average iron content of ferritin based on optical dispersion i.e., how strongly the refractive index changes with wavelength of light. The method is a significant advance over the state of the art method, ELISA used in clinics, because it allows determining the average content of ferritin in a single step. The average iron content of ferritin is an important marker for conditions such as injury, inflammation, and infection.

Areas of interest

Biophysical chemistry; catalysis; charge transfer and transport; clusters and nanoparticles; electrochemistry; environmental chemistry; self-assembly; surface and interfacial chemistry; synchrotron-based characterisation

Representative publication:Effect of Deuteration on Phase Behaviour of Supported Phospholipid Bilayers: A Spectroelectrochemical Study

E. Madrid and S.L. Horswell
Langmuir 31 (2015) 12544-12551

This paper is a study of electric field-induced structural changes observed in asymmetric lipid bilayers, using in situ electrochemical PM-IRRAS. A key potential tool for discriminating between different components of lipid layers is selective deuteration, which is sometimes used in infrared spectroscopy and is standard in neutron studies. This IR study employs selective deuteration to study each half of the bilayer separately. Its significance is that we found that deuteration can alter properties of the ensemble of molecules. Our results mean that care has to be taken when utilising isotopic substitution because even if isotherms of monolayers seem to indicate similar properties in the condensed phases, differences in behaviour of bilayers from which they are formed are still possibilities that should be considered.

Areas of interest

DNA methyltransferases, epigenetics; fluorescence; biophysical chemistry and single molecule imaging

Representative publication: Site-selective and Re-writable Labeling of DNA through Enzymatic, Reversible and Click Chemistries

Andrew A. Wilkinson, Elodie Jagu, Krystian Ubych, Steven Coulthard, Ashleigh E. Rushton, Jack Kennefick, Qiang Su, Robert K. Neely and Paco Fernandez-Trillo, (2020)
ACS Central Science, 6, 4, 525-534

Illustration showing Site-selective and Re-writable Labeling of DNA through Enzymatic, Reversible and Click Chemistries

The paper, a collaboration with Dr Paco Fernandez-Trillo, describes a novel chemistry for the reversible modification of DNA at specific sites of interest. We show that DNA can, for example, be labelled sequentially with two different coloured flurophores. In the lab we are further developing the method to tag, capture and purify DNA for analysis using DNA sequencing. We hope this approach will find application in the early-stage diagnosis of many diseases in the future.

Areas of interest

Surface and interfacial chemistry, electrochemistry, catalysis, clusters and nanoparticles, analytical chemistry, sensors, bio-nanotechnology, self-assembly.

Representative publication: Role of the Adsorbed Oxygen Species in the Selective Electrochemical Reduction of CO2 to Alcohols and Carbonyls on Copper Electrodes

CS Le Duff, MJ Lawrence, P Rodriguez
Angewandte Chemie Int. Ed.129 (2017), 13099-13104

Chemistry diagram showing the Role of the Adsorbed Oxygen Species in the Selective Electrochemical Reduction of CO2 to Alcohols and Carbonyls on Copper Electrodes

This paper provides significant information about the role of oxygen in the electrochemical reduction of CO2 on Cu electrodes. This was achieved using single-crystal electrodes and pulsed voltammetry, since the pulse sequence can be programmed to guarantee reproducible initial conditions for the reaction. In contrast to the selectivity of CO2 reduction using cyclic voltammetry and chronoamperometric methods, a large selection of oxygenated hydrocarbons was found under alternating voltage conditions. Product selectivity towards the formation of oxygenated hydrocarbon was associated to the coverage of oxygen species, which is surface-structure-and-potential dependent.

Contact

Enquiries about specific aspects of their research areas should be addressed to individual research group leaders. For more general enquiries about working with the I2SUnit, please contact the Head of the Section.