In-fiber Photo-immobilization of Bioactive Surfaces: An Optimization Study

Bioactive surface formation within photonic crystal fibers (PCFs) was demonstrated via photochemical means in our earlier work. The bioactive surface consisted of streptavidin bound to a biotin-functionalized layer of protein. Here, we address the issue of non-specific binding between streptavidin molecules and any exposed silica surfaces within the PCF. Increasing the protein coverage mitigated this problem, where a denser coverage was achieved by repeating the protein passivation. Subsequent study on improving the specific binding was also performed by increasing the duration of photobleaching, which resulted in more photochemically bound biotin. Optimal parameters were then selected based upon practicality and repeatability of results.