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Design and Optimization of SiON Ring Resonator-Based Biosensors for Aflatoxin M1 Detection.

Guider R, Gandolfi D, Chalyan T, Pasquardini L, Samusenko A, Pucker G, Pederzolli C, Pavesi L - Sensors (Basel) (2015)

Bottom Line: Sensitivities and limit of detection (LOD) were also measured using glucose-water solutions and compared with expected results from simulations.We were able to detect the binding of aflatoxin for concentrations as low as 12.5 nm.The results open up the path for designing cost-effective biosensors for a fast and reliable sensitive analysis of AFM1 in milk.

View Article: PubMed Central - PubMed

Affiliation: Nanoscience Laboratory, Department of Physics, University of Trento, Via Sommarive 14, Povo (TN) 38123, Italy. romain.guider@unitn.it.

ABSTRACT
In this article, we designed and studied silicon oxynitride (SiON) microring-based photonic structures for biosensing applications. We designed waveguides, directional couplers, and racetrack resonators in order to measure refractive index changes smaller than 10-6 refractive index units (RIU). We tested various samples with different SiON refractive indexes as well as the waveguide dimensions for selecting the sensor with the best performance. Propagation losses and bending losses have been measured on test structures, along with a complete characterization of the resonator's performances. Sensitivities and limit of detection (LOD) were also measured using glucose-water solutions and compared with expected results from simulations. Finally, we functionalized the resonator and performed sensing experiments with Aflatoxin M1 (AFM1). We were able to detect the binding of aflatoxin for concentrations as low as 12.5 nm. The results open up the path for designing cost-effective biosensors for a fast and reliable sensitive analysis of AFM1 in milk.

No MeSH data available.


Optical characterization of the directional coupler for L2 and L5 samples. The optical output ratio represents the optical power at the output waveguide (Pa) versus the sum of the optical power of both output waveguides (Pa + Pb). (inset) Scheme of a directional coupler.
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sensors-15-17300-f005: Optical characterization of the directional coupler for L2 and L5 samples. The optical output ratio represents the optical power at the output waveguide (Pa) versus the sum of the optical power of both output waveguides (Pa + Pb). (inset) Scheme of a directional coupler.

Mentions: As the previous results were really promising concerning the 1000 nm waveguide, we decided to focus the rest of our analysis on waveguides of such dimensions. Concerning the directional coupler measurements, we injected the light into one arm for each directional coupler and check the optical power at the outputs of the same waveguide (Pa) and of the parallel one (Pb). A scheme of the directional coupler device is presented in the inset of Figure 5. The ratio between output power Pa and the sum of output powers (Pa + Pb) is represented in Figure 5 for wafers L2 and L5.


Design and Optimization of SiON Ring Resonator-Based Biosensors for Aflatoxin M1 Detection.

Guider R, Gandolfi D, Chalyan T, Pasquardini L, Samusenko A, Pucker G, Pederzolli C, Pavesi L - Sensors (Basel) (2015)

Optical characterization of the directional coupler for L2 and L5 samples. The optical output ratio represents the optical power at the output waveguide (Pa) versus the sum of the optical power of both output waveguides (Pa + Pb). (inset) Scheme of a directional coupler.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4541935&req=5

sensors-15-17300-f005: Optical characterization of the directional coupler for L2 and L5 samples. The optical output ratio represents the optical power at the output waveguide (Pa) versus the sum of the optical power of both output waveguides (Pa + Pb). (inset) Scheme of a directional coupler.
Mentions: As the previous results were really promising concerning the 1000 nm waveguide, we decided to focus the rest of our analysis on waveguides of such dimensions. Concerning the directional coupler measurements, we injected the light into one arm for each directional coupler and check the optical power at the outputs of the same waveguide (Pa) and of the parallel one (Pb). A scheme of the directional coupler device is presented in the inset of Figure 5. The ratio between output power Pa and the sum of output powers (Pa + Pb) is represented in Figure 5 for wafers L2 and L5.

Bottom Line: Sensitivities and limit of detection (LOD) were also measured using glucose-water solutions and compared with expected results from simulations.We were able to detect the binding of aflatoxin for concentrations as low as 12.5 nm.The results open up the path for designing cost-effective biosensors for a fast and reliable sensitive analysis of AFM1 in milk.

View Article: PubMed Central - PubMed

Affiliation: Nanoscience Laboratory, Department of Physics, University of Trento, Via Sommarive 14, Povo (TN) 38123, Italy. romain.guider@unitn.it.

ABSTRACT
In this article, we designed and studied silicon oxynitride (SiON) microring-based photonic structures for biosensing applications. We designed waveguides, directional couplers, and racetrack resonators in order to measure refractive index changes smaller than 10-6 refractive index units (RIU). We tested various samples with different SiON refractive indexes as well as the waveguide dimensions for selecting the sensor with the best performance. Propagation losses and bending losses have been measured on test structures, along with a complete characterization of the resonator's performances. Sensitivities and limit of detection (LOD) were also measured using glucose-water solutions and compared with expected results from simulations. Finally, we functionalized the resonator and performed sensing experiments with Aflatoxin M1 (AFM1). We were able to detect the binding of aflatoxin for concentrations as low as 12.5 nm. The results open up the path for designing cost-effective biosensors for a fast and reliable sensitive analysis of AFM1 in milk.

No MeSH data available.