Fabrication and testing of surface-enhanced Raman spectroscopy substrates for the detection of biomolecules

Abstract

Biosensing involves the detection of analytes using biological elements as receptor agents for the specific binding of molecules to a surface. Surface-enhanced Raman spectroscopy (SERS), a surface-sensitive vibrational spectroscopy technique used to amplify Raman signals, provides unique advantages for biosensing. Unique Raman fingerprint spectra of targeted molecules allows for accurate identification of unknown samples. Inconsistencies in Raman signal enhancements, however, due to the irregularities of metallic features at the nanoscale, is a significant challenge with SERS. Nanofabrication technologies, including electron beam lithography (EBL) and nanoimprint lithography (NIL), provide resolution capabilities at the nanoscale. In this work, nanofabrication methods were used to fabricate SERS substrates for the detection of analytes using various immobilization strategies. Control over signal intensity and detection of biological bonding, with analytes in aqueous solutions was demonstrated. Investigations and testing of various aspects in the fabrication processes allowed for significant control over features at nanoscale dimensions.