The interface between hard matter (such as minerals, metals, semiconductors) and soft-matter (organic molecules such as polymers and proteins) unites two aspects of the same problem. If we take a mineral surface as given and consider the adsorption of the soft matter upon it, we are addressing aspects of recognition and adaptation of the soft matter, as it accommodates to the environment presented by the mineral surface. The range of soft-matter considered here spans single peptide molecules all the way up to the binding of cells onto surfaces, and includes arrays of soft-matter, covering issues such as epitaxial matching between the soft and hard matter at the interface. This leads to applications in the areas of toxicology of nanoparticles and, ultimately, to the area of bio-remediation in soils. The other side of this problem is to consider the soft-matter as given (e.g. in an array or scaffold) and consider how a hard inorganic material may nucleate and grow at this interface. This process of biomineralisation involves stages of nucleation, templating, confinement effects, inhibition and aggregation. These stages cover a range of time-scales and length-scales, and at each stage, the interface between the soft-matter and hard-matter is crucial. Important applications include the biomimetic design of materials with unique properties, the role of calcium carbonate in carbon capture and oil recovery technologies, and medical applications of interfaces with calcium phosphates, which are major constituents of teeth and bone.
Progress in these areas can only come from dialogue between simulators and experimentalists on an equal footing. Therefore a key feature of our proposal is the large number of invited experts in techniques such as small-angle X-ray scattering and in-situ atomic force microscopy and transmission electron microscopy (used to study nucleation), real-time X-ray microtomography and cryo-TEM (to study surface structure), solid-state NMR (for protein structures), quantitative colloidal force microscopy using AFM probes and time-resolved (emission) anisotropy measurements (for biological cell-surface interactions), SEM, EXAFS, XPES, IR, Raman microscopy, amongst others.
We anticipate that each workshop attendee will find significant interest in at least several of the sessions listed (see Objectives, below). The types of challenges to be discussed in each session could include (but are not limited to) the following:
* What are the most appropriate time- and length-scales in relation to experimental measurements? How may these be addressed by different kinds of simulation?
* Force-field development, in the inorganic material, the organic molecules, and the interface between them. Are our force-fields really up to the job[1,2]? How can we coarse-grain the interactions over the required scales?
* Can enhanced simulation methods or sampling techniques save us [4,5]? They need to address sensitive and specific issues such as biomolecular folding induced by adsorption at the inorganic surface, or directed crystallization under the influence of soft molecular assemblies.
* How can we relate molecular interactions and motion with much longer-time events such as nanoparticle-nanoparticle association and aggregation[7,8]?
The formal talks, and the discussions, will be closely structured around the above themes and all speakers will be expected to address challenges of the above kind as well as simply presenting their recent results. Each session will have designated rapporteurs, with the intention of producing a document summarizing the current state of the field as well as pointers to future research directions.