In situ monitoring of polysaccharide-polynucleotide interaction using a schizophyllan-immobilized QCM device

Schizophyllan belongs to the β-(1 → 3)-d-glucan family and is well known as a triple helix polysaccharide. It is already known that the single chain of schizophyllan (s-SPG) can specifically form a complex with particular polynucleotides. As an application of this recognition capability, a novel schizophyllan derivative connected with a disulfide bond through a long methylene spacer was synthesized, and its interaction with polynucleotides was directly monitored with a self-assembled monolayer on QCM. The gold-coated QCM electrode was covered in ca. 60% as a monolayer of s-SPG. The QCM resonator showed sensitive mass increases for poly(C) and poly(U) in the presence of K⁺ ion, which are consistent with our previous results. The present results indicate that the schizophyllan-immobilized QCM resonator can be a new sensing device for biomolecules.