Characteristic investigation of scanning surface plasmon microscopy for nucleotide functionalized nanoarray

Area of Science:

• Physics
• Materials Science
• Nanotechnology

Background:

• Surface plasmon coupling is crucial for optical phenomena in nanostructures.
• Maxwell-Garnett equation models effective optical properties of composite materials.
• Scanning Surface Plasmon Microscopy (SSPM) offers high-resolution surface analysis.

Purpose of the Study:

• To develop a calculation method for predicting coupling angle shift and thin film thickness using SSPM.
• To investigate the refractive index sensitivity and lateral resolution of the SSPM system.
• To demonstrate the capability of SSPM in imaging nanostructures and functionalized nanoarrays.

Main Methods:

• Calculations based on surface plasmon coupling conditions and the Maxwell-Garnett equation.
• Analysis of coupling angle shifts for determining thin film thickness.
• Investigation of system sensitivity and resolution using ZnO thin films and gold nanodiscs.

Main Results:

• The SSPM system achieved a limit of detection of 0.01° and limit of quantification of 0.03° for angle shifts.
• Sensitivity was approximately 0.12° shift per nm ZnO film for thicknesses below 22.6 nm.
• The system successfully resolved two partially connected gold nanodiscs (1.1 μm separation) and imaged nanostructure defects and a virus-probe functionalized nanoarray.

Conclusions:

• The developed calculation method enables accurate prediction of thin film thickness and coupling angle shifts in SSPM.
• SSPM demonstrates high sensitivity and resolution suitable for nanostructure analysis.
• The technique holds significant potential for future applications in nanobiosensing.