Formation of nanoscale reaction field using combination of top-down and bottom-up nanofabricaiton

We present a novel and simple method of fabricating patterned arrays of gold (Au) nanoparticles on a nanoscale reaction field by combining electron beam lithography and self-assembly techniques. We succeeded in forming a nanoscale reaction field consisting of a single Au nanoparticle or Au nanoparticles on water-soluble dithiol self-assembled monolayer (SAM) nanopatterns such as line and space patterns and dot patterns. Spherical Au nanoparticles were immobilized above the Au nanopatterns with a gap of a few nanometers and supported by two types of water-soluble dithiols. A difference in the attachment behaviors of Au nanoparticles between 3,6-dioxa-1,8-octanedithiol and poly(ethylene glycol) (PEG) dithiol was clearly observed. The patterned nanoscale reaction field is highly controllable and we believe it will contribute to studies on the observation of single biomolecules such as DNA, peptides, nucleic acids, proteins, and cells.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights• We succeeded in the formation of nanoscale reaction field such as Au nanoparticles on the dithiol SAM nano-patterns such as line and space and dots. • This fabrication technique will contribute to studies on the observation of single biomolecules such as DNA, peptides, nucleic acids, proteins, and cells. • A difference in the attachment behaviors of Au nanoparticles in SAM chain lengths was observed.