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Silk-elastin-like proteins (SELPs) are a family of genetically engineered recombinant protein polymers exhibiting mechanical and biological properties suited for a wide range of applications in the biomedicine and materials fields. They are being explored as the next generation of biomaterials but low productivities and use of antibiotics during production undermine their economic viability and safety. We have developed an industrially relevant, scalable, fed-batch process for the high level production of a novel SELP in E. coli in which the commonly used antibiotic selection marker of the expression vector is exchanged for a post segregational suicide system, the separate-component-stabilisation system (SCS). SCS significantly augments SELP productivity but also enhances the product safety profile and reduces process costs by eliminating the use of antibiotics. Plasmid content increased following induction but no significant differences in plasmid levels were discerned when using SCS or the antibiotic selection markers under the controlled fed-batch conditions employed. It is suggested that the absence of competing plasmid-free cells improves host cell viability and enables increased productivity with SCS. With the process developed, 12.8 g L−1 purified SELP was obtained, this is the highest SELP productivity reported to date and clearly demonstrates the commercial viability of these promising polymers.

Biometric technologies already play a major role in security systems contexts and are generally considered for identification and authentication. Some techniques are used in several services not only to ensure physical access to facilities but also to provide some thoroughness in access control. Users generally show concern about security and privacy, but at the same time, wish to use simple mechanisms that facilitate the authentication process in a particular system. Altogether, when implementing such systems it should be guaranteed the purpose of implementation, data protection principles, usability and security, beside taking in consideration the national and international legislation and standards. This study addresses the perception of users regarding the use of biometric authentication technologies in a particular environment, healthcare units. The results derived from a survey indicate a trend of acceptance of such technologies on the access control to health services.

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