A simple optical method using hollow-core photonic crystal fiber for protein detection has been described. In this study, estrogen receptor (ER) from a MCF-7 breast carcinoma cell lysates immobilized inside a hollow-core photonic crystal fiber was detected using anti-ER primary antibody with either AlexaTM Fluor 488 (green fluorescent dye) or 555 (red Fluorescent dye) labeled Goat anti-rabbit IgG as the secondary antibody. The fluorescence fingerprints of the ER protein were observed under fluorescence microscope, and its optical characteristics were analyzed. The ER protein detection by this proposed method is based on immuno binding from sample volume as low as 50 nL. This method is expected to offer great potential as a biosensor for medical diagnostics and therapeutics applications.
A dual-modality fiber scope probe that can simultaneously obtain the spectroscopic signature and images is proposed and illustrated. The photonic crystal fiber and micro CCD camera form the probe distal end. A preliminary experimental investigation using the developed probe has been carried out on phantom tissue stained with fluorophores. Both hollow-core and double-clad photonic crystal fibers have been used at the distal end in separate embodiments, and their collection efficiencies are compared. This proposed probe and methodology are expected to find potential biomedical diagnostics applications.