The website "Materials Views China" introduces our recent work (Y.-L. Sun, Small, 2015) on the protein based optical fiber through femtosecond laser technique. Laborious chemical modifying procedures, biosensing probe proteins (e.g. avidin) were covalently photo-crosslinked and "one-step" FsLDW-customized into all-protein-nanowire optical waveguides for specific biotin-detection.
Excellent designability and repetitiveness were sufficiently demonstrated along with satisfactory morphology (~5-nm roughness average), various designed sizes (as small as ~150 nm) and complex device geometries. Importantly, a transmission window of the protein nanowires were proved to be prceisely near human tissues' (around ~ 680 nm; about 0.05~0.06 dB∙ per μm transmission loss in air for 633 nm light).
As a result, good biocompatibility, adjustable high biosensitivity (0.2 ppb or sensitivities even higher) can be readily realized for these all-protein-based single-nanowire optical biosensors, which might offer new opportunities for novel environment monitoring and biomedical applications.