Limits...
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.


(Left) Sensitivity of the L2 sample; (Right) Sensitivity of the L5 sample.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4541935&req=5

sensors-15-17300-f008: (Left) Sensitivity of the L2 sample; (Right) Sensitivity of the L5 sample.

Mentions: According to the high quality factors measured on covered resonators, we also designed and measured uncovered rings fabricated on the same wafers. These resonators are used as sensors, as the removal of the top cladding layer allows their functionalization. In order to characterize them, we measured their sensitivity as S = Δλ/Δn. To determine the sensitivity of the ring resonator sensors, we monitored the shift of the WGM resonances while exposing the sensor to several glucose-water solutions of different concentrations. More details on this experiment are available in [13]. Figure 8 represents the bulk sensitivity of the L2 and L5 wafers as a function of the polarization.


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)

(Left) Sensitivity of the L2 sample; (Right) Sensitivity of the L5 sample.
© Copyright Policy
Related In: Results  -  Collection

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

sensors-15-17300-f008: (Left) Sensitivity of the L2 sample; (Right) Sensitivity of the L5 sample.
Mentions: According to the high quality factors measured on covered resonators, we also designed and measured uncovered rings fabricated on the same wafers. These resonators are used as sensors, as the removal of the top cladding layer allows their functionalization. In order to characterize them, we measured their sensitivity as S = Δλ/Δn. To determine the sensitivity of the ring resonator sensors, we monitored the shift of the WGM resonances while exposing the sensor to several glucose-water solutions of different concentrations. More details on this experiment are available in [13]. Figure 8 represents the bulk sensitivity of the L2 and L5 wafers as a function of the polarization.

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.