Free radical species generated through fluorescence photobleaching have been reported to effectively couple a water-soluble species to surfaces containing electron-rich sites (
1). In this report, we expand upon this strategy to control the patterned attach
ment of antibodies and peptides to surfaces for biosensing and tissue engineering applications. In the first application, we co
mpare hydrophobic attach
ment and photobleaching
methods to i
mmobilize FITC-labeled anti-M13K07 bacteriophage antibodies to the SiO
2 layer of a differential capacitive biosensor and to the polyester fila
ment of a feedback-controlled fila
ment array. On both surfaces, antibody attach
ment and function were superior to the previously e
mployed hydrophobic attach
ment. Further
more, a laser scanning confocal
microscope could be used for auto
mated, software-guided photoattach
ment che
mistry. In a second application, the cell-adhesion peptide RGDS was site-specifically photocoupled to glass coated with fluorescein-conjugated poly(ethylene glycol). RGDS attach
ment and bioactivity were characterized by a fibroblast adhesion assay. Cell adhesion was li
mited to sites of RGDS photocoupling. These exa
mples illustrate that fluorophore-based photopatterning can be achieved by both solution-phase fluorophores or surface-adhered fluorophores. The coupling preserves the bioactivity of the patterned species, is a
menable to a variety of surfaces, and is readily accessible to laboratories with fluorescence i
maging equip
ment. The flexibility offered by visible light patterning will likely have
many useful applications in bioscreening and tissue engineering where the controlled place
ment of bio
molecules and cells is critical, and should be considered as an alternative to che
mical coupling
methods.