Polysaccharide-coated beads platform for biomolecule analysis: Evolution of SiO2-based suspension arrays

Graphically encoded SiO2-based suspension arrays are often manufactured with the 2D matrixes by popular aldehyde–aminosilane chemistry for the attachment of a variety of biomolecules, including peptides, proteins, nucleic acid probes, etc. In view of the relatively low immobilization efficiency, we have developed a novel method to prepare polysaccharide-coated silica beads, which can increase the binding capacity of biomolecules on silica beads and improve the performance of the stability of biomolecules under various denaturing conditions. In this study, two kinds of representative polysaccharides, chitosan and sodium alginate (NaAlg), were used for the surface coating. And two procedures for the immobilization of protein on NaAlg-coated beads were also studied. Under the optimized experimental conditions, NaAlg-coated beads had excellent biomolecular binding capacities which increased the fluorescence signal by almost 80%. Attending to the results obtained, we believe that the proposed methods may have significant potential for novel SiO2-based suspension array technology.