Locally Functionalized Short-Range Ordered Nanoplasmonic Pores for Bioanalytical Sensing

Abstract

Nanoplasmonic sensors based on short-range ordered nanoholes in thin metal films and discrete metal nanoparticles are known to provide similar sensing performance. However, a perforated metal film is unique in the sense that the holes can be designed to penetrate through the substrate, thereby also fulfilling the role of nanofluidic channels. This paper presents a bioanalytical sensing concept based on short-range ordered nanoplasmonic pores (diameter 150 nm) penetrating through a thin (around 250 nm) multilayer membrane composed of gold and silicon nitride (SiN) that is supported on a Si wafer. Also, a fabrication scheme that enables parallel production of multiple (more than 50) separate sensor chips or more than 1000 separate nanoplasmonic membranes on a single wafer is presented. Together with the localization of the sensitivity to within such short-range ordered nanoholes, the structure provides a two-dimensional nanofluidic network, sized in the order of 100 x 100 microm(2), with nanoplasmon active regions localized to each individual nanochannel. A material-specific surface-modification scheme was developed to promote specific binding of target molecules on the optically active gold regions only, while suppressing nonspecific adsorption on SiN. Using this protocol, and by monitoring the temporal variation in the plasmon resonance of the structure, we demonstrate flow-through nanoplasmonic sensing of specific biorecognition reactions with a signal-to-noise ratio of around 50 at a temporal resolution below 190 ms. With flow, the uptake was demonstrated to be at least 1 order of magnitude faster than under stagnant conditions, while still keeping the sample consumption at a minimum.

Chapter 13. Nanostructured Materials for Biosensor Applications: Comparative Review of Preparation Methods

“…162 At first, a thin metal film with nanoholes is fabricated by colloidal lithography on a Si wafer coated with SiN ( Figure 13.11, i-iv). In the subsequent step, the whole nanostructure is covered with a second SiN layer ( Figure 13.11, v) for the purpose of protection during wet etching of Si wafer.…”

DNA translocation through a periodically patterned nanoprobe

“…The photonic force required to manipulate the biological molecules such as DNA and micron size cells should be ~ 200 pico-newtons [12][13][14][15]. The plasmonic metallic nano-pore can be utilized as a single molecule bio-sensor due to the huge increase of the surface enhanced Raman signal intensity [16][17][18][19][20]. The plasmonic nanochannel on the pyramidal probe can be utilized for biomolecule sensor due to "plasmonic hot spot" formed at the Au nanometer aperture [18,19].…”

“…The plasmonic metallic nano-pore can be utilized as a single molecule bio-sensor due to the huge increase of the surface enhanced Raman signal intensity [16][17][18][19][20]. The plasmonic nanochannel on the pyramidal probe can be utilized for biomolecule sensor due to "plasmonic hot spot" formed at the Au nanometer aperture [18,19]. The microfabricated V-groove cavity type reactor can be utilized for individual bioreactor.…”

Fabrication of photonic force devices for biomolecule dynamics

“…Recently, the DNA translocation experiments using SiN nanopore with electrical bias presented that the electrical force with 100 pN is required to overcome the entrapping force and other resistant force for applied electrical bias of 100 mVolts. [7][8][9][10][11][12][13][14] The nanopore array with 10 nm diameter or less is drilled on thin SiN membrane utilizing high energy electron beam of TEM. However, all of DNA translocation experiments are performed using electrical characterization.…”