Integrated optical devices for lab‐on‐a‐chip biosensing applications

Polyethylene imine (PEI) based immobilization of antibodies is described and the concept is proved on the label free assay of C-Reactive Protein (CRP). This novel immobilization method is composed of a hyperbranched PEI layer which was deposited at a high pH (9.5) on the sensor surface. The free amino groups of PEI were derivatized with neutravidin by Biotin N-hydroxysuccinimide ester and the biotinylated anti-CRP antibody immobilized on this layer. Direct binding assay of recombinant CRP was successfully performed in the low µg/ml concentrations using a label free optical waveguide biosensor.

Section: Figuresupporting

confidence: 94%

Polyethylene imine-based receptor immobilization for label free bioassays

Kurunczi

Hainard

Juhász

et al. 2013

“…The need for reliable, cheap, disposable lab-on-a-chip and point-of-care devices is on the rise [1][2][3][4][5]. These systems are utilized in biotechnology, medical treatment and diagnosis, and in basic research as well [6,7].…”

Section: Introductionmentioning

confidence: 99%

Microfluidic channels laser-cut in thin double-sided tapes: Cost-effective biocompatible fluidics in minutes from design to final integration with optical biochips

Patko

Mártonfalvi

Kovács

et al. 2014

A simple, reliable and cost-effective fluidic channel, fabricated by using double-sided pressure-sensitive tapes, is demonstrated here. A laser-cutting method is applied to engrave structures in sheets of the tapes. After peeling off the tape liners, the structures could be easily integrated at room temperature with label-free optical waveguide biochips without further modifications or additional processing steps. It is shown that the well-defined and controllable height of the channels is advantageous for stopped-flow measurements of analyte binding.The easy fabrication of a fully transparent integrated sensor unit -tape cuvette system is also demonstrated for parallel microscopic investigations. The transparent unit was used to on-line monitor the surface adhesion of Salmonella cells on poly-L-lysine-coated biochip surfaces, followed by the straightforward microscopic visualization of the adhered bacterial cells. The material of the double sided tape is stable in aqueous solutions. Furthermore, its material is biocompatible, making it ideal for biological applications. Excellent, stable and reversible bonding of the microstructured tapes to biocompatible plastic and glass is also demonstrated.The simplicity of the fabrication at ambient temperatures makes the developed processes appealing for lab-on-a-chip applications, particularly if the bonded biochips are precious. / 12

“…In the last expression r| 2 and r^3 are the complex Fresnel coefficients between boundaries and fi* is given by Eqs. (2)(3)(4)(5) where d 2 is the thickness of the second layer, k is the wavelength, n lt n 2 , k\, 1(2 are the real and imaginary parts of the refractive index of the first and second media and 6\, the incident angle.…”

Section: í Id Model Explanationmentioning

confidence: 99%

“…In particular, detecting non-labeled analytes [1 ] have particular interest, mainly due to the simplicity of the sensing protocol, compared with labeled sensors. The most developed tools are based on surface plasmon resonance (SPR) principle broadly reported in the scientific literature [2] as well as interferometry, using for example Mach-Zehnder [3], ring resonator interferometers [4], Young interferometers [5], among many others [6] operating with a variety of waveguides for the sensing optical readout. The complexity of coupling the light from a fiber to these waveguides, and also for taking the bioanalyte to the sensing surface, by means of complex microfluidic circuit might be often considered to be a drawback, although promising results are continuously improving these typologies of biosensors.…”

Section: Introductionmentioning

confidence: 99%

Efficient design and optimization of bio-photonic sensing cells (BICELLs) for label free biosensing

Lavín¹,

Casquel²,

Sanza³

et al. 2013

In previous works we demonstrated the benefits of using micro-nano patterning materials to be used as bio-photonic sensing cells (BICELLs), referred as micro-nano photonic structures having immobilized bioreceptors on its surface with the capability of recognizing the molecular binding by optical transduction. Gestrinone/anti-gestrinone and BSA/anti-BSA pairs were proven under different optical configurations to experimentally validate the biosensing capability of these bio-sensitive photonic architectures. Moreover, Three-Dimensional Finite Difference Time Domain (FDTD) models were employed for simulating the optical response of these structures. For this article, we have developed an effective analytical simulation methodology capable of simulating complex biophotonic sensing architectures. This simulation method has been tested and compared with previous experimental results and FDTD models. Moreover, this effective simulation methodology can be used for efficiently design and optimize any structure as BICELL. In particular for this article, six different BICELL' S types have been optimized. To carry out this optimization we have considered three figures of merit: optical sensitivity, Q-factor and signal amplitude. The final objective of this paper is not only validating a suitable and efficient optical simulation methodology but also demonstrating the capability of this method for analyzing the performance of a given number of BICELLs for label-free biosensing.