Surface Enhanced Raman Spectroscopy Detection of Biomolecules Using EBL Fabricated Nanostructured Substrates

Abstract

Fabrication and characterization of conjugate nano-biological systems interfacing metallic nanostructures on solid supports with immobilized biomolecules is reported. The entire sequence of relevant experimental steps is described, involving the fabrication of nanostructured substrates using electron beam lithography, immobilization of biomolecules on the substrates, and their characterization utilizing surface-enhanced Raman spectroscopy (SERS). Three different designs of nano-biological systems are employed, including protein A, glucose binding protein, and a dopamine binding DNA aptamer. In the latter two cases, the binding of respective ligands, D-glucose and dopamine, is also included. The three kinds of biomolecules are immobilized on nanostructured substrates by different methods, and the results of SERS imaging are reported. The capabilities of SERS to detect vibrational modes from surface-immobilized proteins, as well as to capture the protein-ligand and aptamer-ligand binding are demonstrated. The results also illustrate the influence of the surface nanostructure geometry, biomolecules immobilization strategy, Raman activity of the molecules and presence or absence of the ligand binding on the SERS spectra acquired.

Aptamer-modified nanomaterials: principles and applications

“…The most popular material, chosen not only for its intrinsic properties but also due to facile and well-characterized immobilization of oligonucleotides, is probably gold. While it is being widely utilized as planar material for functionalcoating or as electrode material [65], researchers have also increased efforts in studying gold nanostructures due to their plasmonic properties as well as absorbance, coupling and scattering properties which are depending on their geometry [29,30,37]. Chemisorption of thiols to elemental gold is a wellknown mechanism resulting in stable self-assembled monolayers (SAM) [66,67].…”

Enhanced Biosensing Activity of Bimetallic Surface Plasmon Resonance Sensor

“…Rusmini et al described in depth the various schemes involved in the immobilization of protein [26]. A strong affinity towards the noble metal surfaces is exhibited by the thiol groups which allow the formation of a covalent bond between the metallic atom and the sulphur head group of thiol [27][28][29].…”

Комбинационное Рассеяние Света Молекулами Красителя Метилового Оранжевого На Поверхности Кремния С Ионно-Синтезированными Наночастицами Серебра

“…Однако неоднородность размеров и морфологии частиц, обра-зующихся в растениях, а также проблема извлечения наночастиц из них затрудняют использование этого ме-тода. Помимо химических методов синтеза наночастиц благородных металлов на практике активно используют-ся и физические подходы, такие как лазерная абляция в растворе [11], электронно-лучевая литография [12], ионная имплантация [13] и др.…”