Research project: Looking after our skin

Multi-scale constitutive modelling of skin

The research focus is on the development of structurally-based continuum constitutive models of skin and their efficient finite element implementation for various applications in medicine, cosmetics, pharmaceutics, consumer goods and military. Anisotropic growth models are used to investigate the mechanobiology of skin.

Staff: Dr. Georges Limbert

Sponsor: University of Southampton

Skin wrinkles

The goal of this research is to gain a mechanistic insight into the formation of skin wrinkles (for cosmetic applications) via the development of robust simulation tools based on multiphysics isogeometric finite element techniques.

Staff:

Dr. Georges Limbert

Nanoscale imaging of the skin ultrastructure and image based modelling

The goal of this research is to exploit recent advances in nanoscale imaging of biological structures to develop nano-micro-meso-macroscopic models of the skin.

Staff: Dr. Georges Limbert
          Dr. Anton Page

Sponsor: University of Southampton, Gatan, Oxford, UK

Finite element modelling of skin damage: microneedle penetration and drying stress

Because our skin is our biophysical interface to the internal and external environment it is involved in a wide range of interactions that affect its properties over short and long time scales. For example, variations in the properties of the stratum corneum occurring with age and/or as a result of particular environmental conditions (temperature, humidity, UV exposure, etc) can alter the ability to deliver transdermal therapies in the elderly population and/or those with delicate skin conditions. Of particular concern, are the drying stresses that develop in the stratum corneum and which lead to cracks and chaps.

The goal of this project is to address these types of problems using a combination of physical and computer experiments.

Staff: Dr. Georges Limbert

Students:
Mr. Clément Sart, SupMéca and Ecole Centrale Paris, France

Mr. Fabrice Tchanque-Njike, Ecole Nationale Supérieure des Techniques Avancées, Palaiseau, France

Sponsor: University of Southampton, EPSRC

Multi-physics modelling of skin microclimate

In 1984 and 2009 the percentage of the UK population aged 65 and over was 15 and 16% respectively, representing an increase of 1.7 million people. By 2035, it is projected that 23% of the UK population will be 65 and over (17% in 2010). The ageing process, combined or not with extrinsic effects, results in significant alterations of the biophysical properties of skin which lead to further complications such as skin tears and associated chronic wounds. Pressure sores―estimated to cost between 1.4 and 2.1 billion annually to the NHS (4% of its expenditure)―are directly related to the chemo-mechano-biological response of the skin against a surface. The local temperature and moisture conditions on and around the skin in the weight-bearing regions of the body are termed skin microclimate. Any treatment or device that could minimise―even in small proportion―the onset of superficial pressure sores and restore the functional state has the potential to be a huge staff time and money saver as well as improving significantly the quality of life. A clinically and experimentally validated mathematical/computational model of skin microclimate would be an invaluable tool to perform hypothesis driven research and unravel some of the complex non-linear mechanobiological mechanisms occurring during the formation of pressure ulcers and associated wound healing.

As a first step towards this goal, it is proposed to develop a finite element model of skin microclimate incorporating coupled thermo-mechanical constitutive equations together with an anatomically-based multi-layer structure for skin. The model will be used to simulate the mechanical pressure of a soft synthetic surface against the skin. Particular variables of interest are different types of surface loads (e.g. shear), thermo-mechanical conditions and humidity-dependent mechanical and friction properties (e.g. the stratum corneum softens with humidity while its coefficient of friction against a surface increases).

Staff: Dr. Georges Limbert

Collaborators: Prof. Amit Gefen and Ms Ayelet Levy, Department of Biomedical Engineering, The Iby and Aladar Fleischman Faculty of Engineering, Tel Aviv University, ISRAEL

Sponsor: University of Southampton, Royal Academy of Engineering