| 초록 |
Surface-enhanced Raman scattering (SERS) is a promising molecular detection tool that provides strong Raman signals of molecules near metal nanostructures. Although it is difficult to deposit small target molecules on metal surface selectively, SERS-active microgels have solved this problem while effectively excluding large adhesives. However, poor reproducibility of SERS signals still remains unsolved. In this study, we fabricate microgels that contain highly-concentrated gold nanoparticles in the absence of agglomerates. We prepare water-in-oil-in-water double-emulsions that contain gold nanoparticles and hydrogel precursors in the water core using microfluidic devices and impose positive osmotic pressure. As water is pumped out through oil shell, core matters are highly concentrated by a factor of 10-50 and the gold nanoparticles are finally trapped in microgels through gelation. The microgels provide high detection sensitivity, molecular selectivity, and signal reproducibility. |
