기능성 압타머 프로브를 이용한 혈관내피세포성장인자 정량분석

Abstract

Angiogenesis is a highly-regulated process of forming new blood vessels. It is known that VEGF (vascular endotherial growth factor) is a prominent regulator for both of the physiological and pathological angiogenesis. Thus, VEGF is considered to be a very useful marker for a tumor angiogenesis. In this study, we developed a new class of Au/Ag core/shell nanoparticles encapsulated with CV and applied these nanoparticles to the ELISA-based bioanalysis. The VEGF aptamer-embedded Au/Ag core/shell nanoparticles were manufactured as follows. The Raman reporters were bound onto the gold nanoparticle by electrostatic interaction. Thiolated aptamer was bound to the gold surface in a particular orientation without losing its affinity for VEGF. Then this particle was coated with silver for a stronger SERS enhancement than bare gold. This silver layer is also working for the protection of the adsorbed Raman reporters from being desorbed from the nanoparticle surface. The proposed VEGF aptamer-embedded Au/Ag core/shell nanoparticle is evaluated to be used as an immunoassay. It successfully detected VEGF antigen as low as 5 ng/mL. Our optical probe is believed to be further utilized to cancer-cell imaging.