Bio-functionalization of inner surfaces of all silica Hollow Core–Photonic Crystal Fibers (HC-PCF) has been
investigated. The approach is based on layer-by-layer self-assembly Peptide Nucleic Acid (PNA) probes, which is an
oligonucleotide mimic that is well suited for specific DNA target recognition. Two kinds of HC-PCFs have been
considered: a photonic Bragg fiber and a hollow core (HC-1060) fiber. After spectral characterization and internal
surface functionalization by using PNA probes, genomic DNA solutions from soy flour were infiltrated into the fibers.
The experimental results indicate that hybridization of the complementary strand of target DNA increases the thickness
of the silica layer and leads up to the generation of surface modes, resulting in a significant modulation of the
transmission spectra. Numerical analysis confirms such behavior, suggesting the possibility to realize biological