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We present radio-frequency (RF) heating-assisted nanoimprint lithography (NIL) for the rapid fabrication of nanostructured biochips. The chips were spin-coated using a RF-sensitive polymer film, namely polyethylene terephthalate glycol-modified (PETG). The RF heating process takes advantage of rapid temperature increases and cooling for NIL. Using a patterned nickel film as the mold, various nanostructures, such as nanowire, nanorod, and nanogrid arrays, were successfully fabricated within several seconds. For surface plasmon biosensing chips, the silver-coated nanowire arrays achieved a linewidth of 6.01 nm and wavelength sensitivity of 550 nm per refractive index unit. The functionality of the sensor was verified by observing the label-free antigen–antibody interactions.

We present the dynamic study of optical trapping of fluorescent molecules using high-density gold nanodisk arrays. The gold nanodisks were fabricated by electron beam lithography with a diameter of 500 nm and a period of 1 μm. Dark-field illumination showed ∼15 times enhancement of fluorescence near edges of nanodisks. Such enhanced near-field generated an optical trapping force of ∼10 fN under 3.58 × 103 W/m2 illumination intensity as calculated from the Brownian motions of 590 nm polystyrene beads. Kinetic observation of thiolated DNA modified with Cy5 dye showed different binding rates of DNA under different illumination intensity. The binding rate increased from 2.14 × 103 s−1 (I = 0.7 × 103 W/m2) to 1.15 × 105 s−1 (I = 3.58 × 103 W/m2). Both enhanced fluorescence and binding rate indicate that gold nanodisks efficiently improve both detection limit and interaction time for microarrays.