Web Date: December 16, 2009
Without any fluorescent tags, a new bioanalytical technology can simultaneously measure multiple clinically relevant biomarkers from a single sample with no decrease in sensitivity. The technique could improve disease diagnostics.
Label-free biosensing technologies such as surface plasmon resonance spectroscopy appeal to researchers because they avoid interference from fluorescent or other tags. But these platforms can sometimes lose sensitivity when measuring multiple analytes simultaneously. Now, Ryan C. Bailey and students Adam L. Washburn, Matthew S. Luchansky, and Adrienne L. Bowman of the University of Illinois, Urbana-Champaign, have developed a system that has no such sensitivity trade-off.
The technology relies on an established type of silicon microstructure functionalized with antibodies. The structures, called silicon photonic micro-ring resonators, are highly sensitive to changes in refractive index that occur when a biomarker binds its corresponding antibody. The team used an array of resonators to quantify five disease biomarkers in a buffered sample at the same time (Anal. Chem., DOI: 10.1021/ac902451b).
The researchers are now testing chemical coatings and other strategies to reduce nonspecific protein binding to the array. "Our structures are made with standard semiconductor processing methods," so they could be mass produced, Bailey says.
The system "is a very promising platform for multiplexed protein detection with sensitivity that will rival surface plasmon resonance," says Thomas Kodadek, a chemical biologist at Scripps Florida.
- Chemical & Engineering News
- ISSN 0009-2347
- Copyright © American Chemical Society