Open Access
Optical fiber sensors based on indium tin oxide surface plasmon resonance supporting coatings
(SPIE, 2009-10-05) Ruiz Zamarreño, Carlos; Hernáez Sáenz de Zaitigui, Miguel; Matías Maestro, Ignacio; Arregui San Martín, Francisco Javier; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In this work, surface plasmon resonance (SPR) based optical fiber sensors are revisited by using a transparent conductive coating, Indium Tin Oxide in our case, as the SPR supporting layer. The utilization of these coatings shifts the plasmon resonance band to the infra-red region and allows the tunability of the SPR wavelength by adjusting the film fabrication parameters. Here, we study the fabrication process of these novel devices and characterize their response to variations in the refractive index of the external medium opening the door to a wide range of applications.
Open Access
Femtomolar detection by nanocoated fiber label-free biosensors
(American Chemical Society, 2018) Chiavaioli, Francesco; Zubiate Orzanco, Pablo; Del Villar, Ignacio; Ruiz Zamarreño, Carlos; Giannetti, Ambra; Tombelli, Sara; Trono, Cosimo; Arregui San Martín, Francisco Javier; Matías Maestro, Ignacio; Baldini, Francesco; Institute of Smart Cities - ISC; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa; Gobierno de Navarra / Nafarroako Gobernua
The advent of optical fibre-based biosensors combined with that of nanotechnologies has provided an oppor-tunity for developing in situ, portable, lightweight, versatile and high-performance optical sensing platforms. We report on the generation of lossy mode resonances by the deposition of nm-thick metal oxide films on optical fibres, which makes it possible to measure precisely and accurately the changes in optical properties of the fibre-surrounding medium with very high sensitivity compared to other technology platforms, such as long period gratings or surface plasmon resonances, the gold standard in label-free and real-time biomolecular interaction analysis. This property, combined with the application of specialty structures such as D-shaped fibres, permits enhancing the light-matter interaction. SEM and TEM imaging together with X-EDS tool have been utilised to characterise the two films used, i.e. indium tin oxide and tin dioxide. More-over, the experimental transmission spectra obtained after the deposition of the nanocoatings have been numerically cor-roborated by means of wave propagation methods. With the use of a conventional wavelength interrogation system and ad-hoc developed microfluidics, the shift of the lossy mode resonance can be reliably recorded in response to very low analyte concentrations. Repeated experiments confirm a big leap in performance thanks to the capability to detect femtomolar concentrations in human serum, improving the detection limit by three orders of magnitude when compared with other fibre-based configurations. The biosensor has been regenerated several times by injecting sodium dodecyl sul-phate, which proves the capability of sensor to be reused.
Open Access
High sensitive refractometers based on lossy mode resonances (LMRs) supported by ITO coated D-shaped optical fibers
(Optical Society of America, 2015) Zubiate Orzanco, Pablo; Ruiz Zamarreño, Carlos; Del Villar, Ignacio; Matías Maestro, Ignacio; Arregui San Martín, Francisco Javier; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
Tin doped indium oxide (ITO) coatings fabricated onto D-shaped optical fibers are presented as the supporting medium for Lossy Mode Resonances (LMRs) generation. The characteristic geometry of ITO-coated D-shaped optical fibers enables to observe experimentally LMRs obtained with both TM and TE polarized light (LMRTM and LMRTE). This permits to obtain a maximum transmission decay of 36 dB with a LMR spectral width of 6.9 nm, improving that obtained in previous works, where the LMRs were a combination of an LMRTM and an LMRTE. Surrounding medium refractive index (SMRI) sensitivity characterization of LMRTM has been performed obtaining a maximum sensitivity of 8742 nm/RIU in the range 1.365-1.38 refractive index units (RIU) which overcomes that of surface plasmon resonance-based optical fiber devices presented in recent works.
Open Access
Optical fiber refractometers based on indium tin oxide coatings with response in the visible spectral region
(Elsevier, 2011) Ruiz Zamarreño, Carlos; López, S.; Hernáez Sáenz de Zaitigui, Miguel; Del Villar, Ignacio; Matías Maestro, Ignacio; Arregui San Martín, Francisco Javier; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa; Gobierno de Navarra / Nafarroako Gobernua
This work presents the fabrication of optical fiber refractometers based on indium tin oxide (ITO) coatings with response in the visible spectral region. ITO thin-films have been sputtered by employing a rotating mechanism that enables the fabrication of smooth homogeneous coatings onto the optical fiber core. The ITO coated optical fiber devices present several resonances in the visible and infra-red region. These resonances show high optical power attenuations (more than 10 dB) in the visible spectral region, which produces changes in the colour of the output visible light. Therefore, since these resonances shift as a function of the surrounding medium refractive index (SMRI), it is feasible to determine the refractive index of the outer medium in contact with the ITO coating by simply monitoring the chromatic coordinates of the visible output light.
Open Access
A fiber optic ammonia sensor using a universal pH indicator
(MDPI, 2014) Rodríguez Rodríguez, Adolfo Josué; Ruiz Zamarreño, Carlos; Matías Maestro, Ignacio; Arregui San Martín, Francisco Javier; Cruz, René; May Arrioja, Daniel A.; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
A universal pH indicator is used to fabricate a fiber optic ammonia sensor. The advantage of this pH indicator is that it exhibits sensitivity to ammonia over a broad wavelength range. This provides a differential response, with a valley around 500 nm and a peak around 650 nm, which allows us to perform ratiometric measurements. The ratiometric measurements provide not only an enhanced signal, but can also eliminate any external disturbance due to humidity or temperature fluctuations. In addition, the indicator is embedded in a hydrophobic and gas permeable polyurethane film named Tecoflex®. The film provides additional advantages to the sensor, such as operation in dry environments, efficient transport of the element to be measured to the sensitive area of the sensor, and prevent leakage or detachment of the indicator. The combination of the universal pH indicator and Tecoflex® film provides a reliable and robust fiber optic ammonia sensor.
Open Access
Ultra-low detection limit lossy mode resonance-based fibre-optic biosensor
(Optica Publishing Group, 2018) Chiavaioli, Francesco; Zubiate Orzanco, Pablo; Del Villar, Ignacio; Ruiz Zamarreño, Carlos; Giannetti, Ambra; Tombelli, Sara; Trono, Cosimo; Matías Maestro, Ignacio; Arregui San Martín, Francisco Javier; Baldini, Francesco; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Institute of Smart Cities - ISC
We report on ultra-low detection limit lossy mode resonance-based fibre-optic biosensor coated with nm-thick tin dioxide film, which allows measuring fibre-surrounding medium changes with very high sensitivity for label-free and real-time biomolecular interaction analysis
Open Access
Generation of surface plasmon resonance and lossy mode resonance by thermal treatment of ITO thin-films
(Elsevier, 2014) Del Villar, Ignacio; Ruiz Zamarreño, Carlos; Hernáez Sáenz de Zaitigui, Miguel; Sánchez Zábal, Pedro; Arregui San Martín, Francisco Javier; Matías Maestro, Ignacio; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
Silicon wafers coated with IndiumTinOxide (ITO) by application of sputtering technique have been characterized after different post-annealing techniques, showing that this last factor is critical for the quality of the thin-film and for the creation and tuning of both surface plasmon resonances and lossy mode resonances. By adequate selection of the ITO thin-film thickness both resonances can be tracked in the same spectrum, which can be used in sensor and optical communications fields.
Open Access
Generation of lossy mode resonances with absorbing thin-films
(IEEE, 2010) Del Villar, Ignacio; Ruiz Zamarreño, Carlos; Hernáez Sáenz de Zaitigui, Miguel; Arregui San Martín, Francisco Javier; Matías Maestro, Ignacio; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
The generation of lossy mode resonances with absorbing thin-films is analyzed with electromagnetic theory. The main differences with surface plasmon resonances are presented and some rules are given towards an optimum design of sensing devices based on absorbing thin-film coated silica substrates. The material selected for the absorbing thin-film is ITO, which is adequate for supporting both surface plasmon resonances and lossy mode resonances.
Open Access
Rheumatoid arthritis miRNA biomarker detection by means of LMR based fiber-optic biosensor
(IEEE, 2020) Imas González, José Javier; Ruiz Zamarreño, Carlos; Zubiate Orzanco, Pablo; Campión, J.; Sánchez-Martín, L.; Matías Maestro, Ignacio; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, PJUPNA26
Development of miRNA optical biosensors for disease diagnosis and monitoring has acquired relevance in recent years, due to the clinical importance of miRNA and the inherent advantages of optical sensors. Here, we present the utilization of a fiber optic sensor based on Lossy Mode Resonance (LMR) for the detection of miRNA hsa-miR-223, a promising biomarker for the diagnosis of rheumatoid arthritis (RA).
Open Access
Optical sensors based on lossy-mode resonances
(Elsevier Science, 2017) Matías Maestro, Ignacio; Ascorbe Muruzabal, Joaquín; Acha Morrás, Nerea de; López Torres, Diego; Zubiate Orzanco, Pablo; Sánchez Zábal, Pedro; Urrutia Azcona, Aitor; Socorro Leránoz, Abián Bentor; Rivero Fuente, Pedro J.; Hernáez Sáenz de Zaitigui, Miguel; Elosúa Aguado, César; Goicoechea Fernández, Javier; Bariáin Aisa, Cándido; Corres Sanz, Jesús María; Ruiz Zamarreño, Carlos; Arregui San Martín, Francisco Javier; Del Villar, Ignacio; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa; Institute of Smart Cities - ISC