Development of a Miniaturized Bio-Barcode Sensor Array for Detection of Biological Events

Various optical transduction methods have been developed for use with biosensor technologies. Currently, one of the promising methods that is utilized in this research are surface plasmon resonance (SPR)-based optical ones. Limited number of crucially-needed in vivo detection devices have been developed up to date. The main challenges that hinder development of such devices are the lack of adequate energy sources and reliable communication capabilities between the body and the external environment.

To overcome these challenges, we present a novel versatile bio-barcode optical sensor array for detection of biological event towards in vivo detection. The sensor comprising of nanocavities for confining the electromagnetic field to an area of ≈60 nm², nanoparticles and fluorescence, allows milti-detection of biological events using SPR and fluorescence lifetime.

Various designs of nanocavities were manufactured on a gold thin film utilizing Focused Ion Beam (FIB) milling instrumentation. GNPs were conjugated to the surface using PEGs and custom designed peptide that are cleaved by various enzymes at specific site. Fluorescein dye was conjugated to GNP using PEG.

The GNPs were removed from the surface using enzymes and change in signal was measured using confocal microscope and Fluorescence Life Time Imaging (FLIM) system. A change is SPR and FLIM was observed as a result of GNP removal, while each array displayed different spectrum forming a basis for multisensing of biological events on single substrate.

In this research we realized a miniaturized multisensting versatile platform to be utilized for detection of biological events. This is a first step towards realization of a more versatile system to be tested in vivo using NIR fluorescence. We believe that the proposed sensor array will pave the way towards next-generation biosensors, indicating early onset of conditions such as heart attack or cancer progression.