Optical fiber nanotips as carriers for molecular beacon-based biosensors

Here we present some preliminary results concerning the use of a fibre optical nanotip with a molecular beacon (MB) immobilized for cancer theranostics. The solid support chosen as substrate for the immobilization of the MB was a tip of an optical fibre tapered at nanoscale size, intended to be used in the future to probe directly inside the cytoplasm of living cells. The nanotip was fabricated by chemical etching, starting from 500 micron - diameter multimode optical fibre down to 100 nm at the tip. Next, the fibre tips were silanized, and MB attached via covalent-binding procedure.