Photobleaching induced damage of biomolecules: Streptavidin as ‘bio’-photoresist

2-dimensional patterning of surfaces in order to address biological questions is of central interest for the investigation of cell–surface interactions and biosensing. e report on an approach which makes use of photobleaching of fluorescently-labelled surface-immobilized streptavidin as ‘bio’-photoresist in order to locally in situ interact with surfaces. Reactive oxygen created during the photobleaching process is likely to be involved in this novel surface manipulation process and its effect on surface-immobilized moieties was investigated by Optical Waveguide Lightmode Spectroscopy (OWLS) and on pre-patterned surfaces using fluorescent microscopy. The creation of bio-patterns as an application of this effect was demonstrated by locally exchanging streptavidin and phospholipid vesicles. ovel surface modification method is interesting from the engineering point of view since no harsh conditions are required and therefore the ‘bio’-photoresist streptavidin allows for the manipulation of surfaces in situ in aqueous solutions e.g., for cell studies.