Skip to main content Skip to navigation

Understanding how molecules are delivered to biosurfaces from evaporating droplets

Supervisor: Patrick Unwin (Chemistry) & Co-supervisor: Stanley Lai (Syngenta)

This PhD project in collaboration with Syngenta, a global crop protection and seeds company, aims to understand the basic physical processes involved in the delivery (absorption and adsorption) of active ingredients (AIs) from tiny droplets. This process is central to the application of AIs that protect crops. Typically, agrochemicals are delivered to target crops through spraying applications. This leads to aqueous droplets containing the active ingredient (AI) and other formulation components on the surface of the crop, from which the AI needs to be absorbed by the plant surface to be biologically efficacious. However, once a droplet is on the plant surface, it can be subject to many physical and chemical processes, and the overall effect is challenging to understand and predict.

This project aims to visualise and track the concentrations of molecular species of interest (such as the AI) through electrochemical and optical (including confocal microscopy) monitoring after a droplet is applied. In particular, a key aim is to develop the methodology to track concentrations in situ in real spray-sized droplets, a unique capability which does not currently exist. Using this methodology, the various related factors which affect these concentrations can be disentangled (including droplet composition and characteristics, evaporation of the solvent, uptake of the molecular species by the plant surface, and chemical (e.g. degradation) and physical (e.g. volatilisation) losses) and new fundamental understanding on the processes involved in delivery from droplets can be generated. Armed with this understanding, strategies can then be developed to steer the desired (uptake) pathways and minimise the undesired (losses) effects.

This is an ideal project for a PhD student who enjoys problem solving and interdisciplinary research, involving analytical and physical chemistry, microscopy, modelling and data analysis. There will be a chance to learn many desirable scientific skills of wide applicability, embracing electrochemical methods, microscopy, instrumentation, surface chemistry, scientific programming and data visualization, as well as key transferable skills.

The project will be in the Warwick Electrochemistry and Interfaces Group (WEIG), which has outstanding facilities and reputation for the development and use of innovative (imaginative) techniques. The Warwick group has a longstanding relationship with Syngenta on the development of innovative methods for understanding the efficacy and mode of action of delivery systems. This project will provide a platform that will address an important general problem in agriscience (that also extends to the pharmaceutical area), and also provides a great opportunity for considerable advances in fundamental measurement science and surface/interfacial science.

This project is suitable for students with a background in the physical, mathematical and life sciences (Chemistry, Physics, Pharmacy, Maths, or Biology/Biochemistry) and the successful applicants will have a minimum of a 2:1 first degree in a relevant discipline/subject area.

For further details please contact Professor Patrick Unwin:

Start date: 27 September 2021

This position has now been filled.