Thermodynamic study of interactions between ZnO and ZnO binding peptides using isothermal titration calorimetry

Whilst material specific peptide binding sequences have been identified using a combination of combinato-rial methods and computational modelling tools, a deep molecular level understanding of the fundamental principles through which these interactions occur and in some instances modify the morphology of inorganic materials is far from being fully realized. Understanding the thermodynamic changes that occur during peptide-inorganic interactions and correlating these to structural modifications of the inorganic materials could be the key to achieving and mastering con-trol over material formation processes. This study is a detailed investigation applying isothermal titration calorimetry (ITC) to directly probe thermodynamic changes that occur during interaction of ZnO binding peptides (ZnO-BPs) and ZnO. The ZnO-BPs used are reported sequences G-12 (GLHVMHKVAPPR), GT-16 (GLHVMHKVAPPR-GGGC) and alanine mutants of G-12 (G-12A6, G-12A11 and G-12A12) whose interaction with ZnO during solution synthesis studies have been extensively investigated. The interactions of the ZnO-BPs with ZnO yielded biphasic isotherms comprising both an endo-thermic and an exothermic event. Qualitative differences were observed in the isothermal profiles of the different pep-tides and ZnO particles studied. Measured ΔG values were between -6 and -8.5 kcal/mol and high adsorption affinity val-ues indicated the occurrence of favourable ZnO-BP-ZnO interactions. ITC has great potential in its use to understand peptide-inorganic interactions and with continued development, the knowledge gained may be instrumental for simplifi-cation of selection processes of organic molecules for the advancement of material synthesis and design

In Search of a Trade Mark: Search Practices and Bureaucratic Poetics

Trade marks have been understood as quintessential ‘bureaucratic properties’. This article suggests that the making of trade marks has been historically influenced by bureaucratic practices of search and classification, which in turn were affected by the possibilities and limits of spatial organisation and technological means of access and storage. It shows how the organisation of access and retrieval did not only condition the possibility of conceiving new trade marks, but also served to delineate their intangible proprietary boundaries. Thereby they framed the very meaning of a trade mark. By advancing a historical analysis that is sensitive to shifts, both in actual materiality and in the administrative routines of trade mark law, the article highlights the legal form of trade mark as inherently social and materially shaped. We propose a historical understanding of trade mark law that regards legal practice and bureaucratic routines as being co-constitutive of the very legal object itself