Label-free detection of tumor angiogenesis biomarker angiopoietin 2 using bloch surface waves on one dimensional photonic crystals
File(s)
Author(s)
Type
Journal Article
Abstract
We describe the design and fabrication of biochips based on 1-D photonic crystals supporting Bloch surface waves for label-free optical biosensing. The optical properties of Bloch surface waves are studied in relation to the geometry of the photonic crystals and on the properties of the dielectric materials used for the fabrication. The planar stacks of the biochips are composed of silica, tantala, and titania that were deposited using plasma-ion-assisted evaporation under high-vacuum conditions. The biochip surfaces were functionalized by silanization, and appropriate fluidic cells were designed to operate in an automated platform. An angularly resolved ellipsometric optical sensing apparatus was assembled to carry out the sensing studies. The angular operation is obtained by a focused laser beam at a fixed wavelength and detection of the angular reflectance spectrum by means of an array detector. The results of the experimental characterization of the physical properties of the fabricated biochips show that their characteristics, in terms of sensitivity and figure of merit, match those expected from the numerical simulations. Practical application of the sensor was demonstrated by detecting a specific glycoprotein, Angio-poietin 2, that is involved in angiogenesis and inflammation processes. The protocol used for the label-free detection of Angiopoietin 2 is described, and the results of an exemplary assay, carried out at a relatively high concentration of 1 μg/ml, are given and confirm that an efficient detection can be achieved. The limit of detection of the biochips for Angiopoietin 2, based on the protocol used, is 1.5 pg/mm2 in buffer solution. The efficiency of the label-free assay is confirmed by independent measurements carried out by means of confocal fluorescence microscopy.
Date Issued
2015-06-25
Date Acceptance
2015-06-17
Citation
Journal of Lightwave Technology, 2015, 33 (16), pp.3385-3393
ISSN
1558-2213
Publisher
Institute of Electrical and Electronics Engineers (IEEE)
Start Page
3385
End Page
3393
Journal / Book Title
Journal of Lightwave Technology
Volume
33
Issue
16
Copyright Statement
© 2015 IEEE. Personal use is permitted, but republication/redistribution requires IEEE permission.
See http://www.ieee.org/publications standards/publications/rights/index.html for more information.
See http://www.ieee.org/publications standards/publications/rights/index.html for more information.
Sponsor
Commission of the European Communities
Identifier
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000359566000003&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
Grant Number
FP7-ICT-2011-8 318035
Subjects
Science & Technology
Technology
Physical Sciences
Engineering, Electrical & Electronic
Optics
Telecommunications
Engineering
Angiopoietin 2
APTES
Bloch surface waves
ELFA
Enzyme linked fluorescence assay
Label-free optical sensors
Optical biosensors
Optical multilayer systems
Photonic crystal
Protein G
Sensors
Biosensors
Optoelectronics & Photonics
Optical Physics
Electrical And Electronic Engineering
Communications Technologies
Publication Status
Published