Improved antifouling properties and selective biofunctionalization of stainless steel by employing heterobifunctional silane-polyethylene glycol overlayers and avidin-biotin technology.

A straightforward solution-based method to modify the biofunctionality of stainless steel (SS) using heterobifunctional silane-polyethylene glycol (silane-PEG) overlayers is reported. Reduced nonspecific biofouling of both proteins and bacteria onto SS and further selective biofunctionalization of the modified surface were achieved. According to photoelectron spectroscopy analyses, the silane-PEGs formed less than 10 Å thick overlayers with close to 90% surface coverage and reproducible chemical compositions. Consequently, the surfaces also became more hydrophilic, and the observed non-specific biofouling of proteins was reduced by approximately 70%. In addition, the attachment of E. coli was reduced by more than 65%. Moreover, the potential of the overlayer to be further modified was demonstrated by successfully coupling biotinylated alkaline phosphatase (bAP) to a silane-PEG-biotin overlayer via avidin-biotin bridges. The activity of the immobilized enzyme was shown to be well preserved without compromising the achieved antifouling properties. Overall, the simple solution-based approach enables the tailoring of SS to enhance its activity for biomedical and biotechnological applications.

Cumulative prevalence of atopic eczema and related skin symptoms in a well-baby clinic: a retrospective cohort study.

The aim of the study was to assess the frequency and treatment policy of atopic eczema (AE) and related skin symptoms including rash, redness, dryness and itch in 0- to 5-year-old children. Health records of 320 children born in 1994 were systematically studied. The main results were that 77% of children suffered from skin symptoms during their first 5 years while the cumulative prevalence of AE was 16%, and 11% of children with skin symptoms were referred to a specialist. AE and related skin symptoms were common in the first 5 years of life, and were mostly temporary and responsive to topical treatment. Well-baby clinics play a key role in the treatment of skin-symptomatic children.