Fabrication of glyconanoparticle microarrays

Abstract

We report a new type of microarray, based on glyconanoparticles (GNPs), to study glycan-lectin interactions. GNPs, synthesized by conjugating carbohydrate ligands on silica nanoparticles, were printed on a photoactive surface followed by covalent immobilization by light activation. The GNP microarrays could be probed by lectins labeled with fluorescein as well as fluorescein-doped silica nanoparticles (FSNPs). Results showed that FSNP as the label enhanced the signals for the higher affinity ligands than the lower ones.

Figure 1

Fluorescence intensity of Man-GNP microarrays probed with FSNP-Con A (I) or FITC-Con A (II). In III and IV, no polymer coating was used and the Man-GNP microarrays were incubated in BSA before treating with FSNP-Con A (III) or FITC-Con A (IV). The data points were connected with lines to aid visualization.

Figure 2

(a) Fluorescence images of GNP microarrays probed with FSNP-Con A (i) or FITC-Con A (iii), and carbohydrate microarrays probed with FSNP-Con A (ii) or FITC-Con A (iv). (b) Fluorescence intensity of the four arrays in (a). Each data point was the average of the 3 spots in (a), and the error bars were omitted for clarity.

Scheme 1

Preparation of GNP microarrays and interactions with FSNP-Con A or FITC-Con A.