Rapid detection of S-adenosyl homocysteine using self-assembled optical diffraction gratings

Ghanashyam Acharya, Purdue University
Chun-Li Chang, Purdue University
David Preston Holland, Purdue University - Main Campus
David H. Thompson, Department of Chemistry, Purdue University
Cagri Savran, Birck Nanotechnology Center and School of Mechanical Engineering, Purdue University

Abstract

Quantitative characterization of biomolecules is critical for molecular diagnostics and drug development.[1, 2] Several assays based on spectrophotometry,[3, 4] fluorometry,[5] chemiluminescence,[ 6] and electrochemical immunoassays have been reported for biomolecular detection.[7–9] These methods are often slow owing to multiple sample pretreatment steps that increase analysis time and cost. Immunoassays that combine high sensitivity with fast, robust, and inexpensive methods for biomolecular detection are of growing importance.[ 10] Herein the development of a self-assembled optical diffraction biosensor is described which is devoid of microfabrication[ 11] or enzymatic amplification[12] for the rapid detection of S-adenosyl homocysteine (SAH), a potential diagnostic marker for cardiovascular disease,[13] with a sensitivity limit of 24.5pg mL.