The importance of understanding the interactions between nanoscale materials and living matter has now begun to be appreciated by an extraordinaryly large range of stakeholders, including ...researchers, industry, governments and society, all of whom appreciate both the opportunities presented by and challenges raised by this arena of research. Not only does it open up new directions in nanomedicine and nanodiagnostics, but it also offers the chance to implement nanotechnology across all industry in a safe and responsible manner. The underlying reasons for this arena as a new scientific paradigm are real and durable. Less than 100 nm nanoparticles can enter cells, less that 40 nm they can enter cell nucleus, and less that 35 nm they can pass through the blood brain barrier. These are fundamental length scales of biological relevance that will ensure that engineered nanoscience will impinge on biology and medicine for many decades to come. One important issue is the current lack of reproducibility of the outcomes of many experiments in this arena. Differences are likely a consequence of such things as uncontrolled nanoparticle aggregation leading to unpredictable doses being presented to cells, interference of the nanoparticles themselves with many of the tests being applied, differences in the degree of confluency of the cells used, and a host of other factors. NanoInteract has shown how careful control of all aspects of the test system, combined with round robin type approaches, can help resolve these issues and begin to ensure that the field can become a quantitative science. The basic principle of NanoInteract is that given identical nanomaterials, cells and biological materials, and using a common protocol, experiments must yield identical answers. Thus, any deviations result from errors in (applying) the protocol which can be tracked and eliminated, until quantitatively reproducible results are obtained by any researcher in any location. This paper outlines the NanoInteract programme, illustrates key advances, and highlights early successes. (www.nanointeract.net)
Using a simplified microstructural picture we show that interactions between thermosenstive microgel particles can be described by a polymer brush like corona decorating the dense core. The softness ...of the potential is set by the relative thickness \(L_0\) of the compliant corona with respect to the overall size of the swollen particle \(R\). The elastic modulus in quenched solid phases derived from the potential is found in excellent agreement with diffusing wave spectroscopy (DWS) data and mechanical rheometry. Our model thus provides design rules for the microgel architecture and opens a route to tailor rheological properties of pasty materials.
The role of proteins as the mediators of the interaction between engineered materials (biomaterials) and living systems has long been appreciated, but the subtleties and complexities introduced by ...changing surface curvature are only beginning to be understood. Thus, in implant devices, where the biomaterial is presented as a flat surface, a very limited range of proteins bind to the material, these being mainly albumin and fibrinogen. However, as the surface curvature increases (as we move towards micro and nano scale particles) novel effects are observed, and the materials begin to bind rarer specialized proteins with very high affinity, which has significant consequences for their biocompatibility and for their impacts on the biological system with which they interact. In the present work we present some findings from the EU project SIGHT in which the interactions of polymeric microballoons (gas-filled polymer-shelled devices that are being developed as contrast agents for theranostic applications) with plasma proteins are investigated, and the potential consequences for long term biocompatibility are discussed.
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