Bulk and surface sensitivity of a resonant waveguide grating imager

Design of grating couplers and MMI couplers on the TriPleX platform enabling ultra-compact photonic-based biosensors

“…LoC platforms based on high Q micro-ring resonators (MRRs) in particular have been proved to be capable of being combined with microfluidic structures and detecting a large variety of analytes with very high sensitivity in the change of the refractive index on biochemically modified surfaces, which is in the order of 10 −6 -10 −7 refractive index units (RIU) [5]. Compared to other interferometric devices based on reverse symmetry waveguides [6], resonant grating structures [7] and grating coupled optical waveguides [8], as well as devices based on optical waveguide lightmode spectroscopy (OWLS) [9], the MRR-based devices offer a similar level of sensitivity for the detection of small molecules, but they are much simpler in their operating principle and their implementation, and have a much larger potential for the integration of the photonic part and the miniaturization of the sensor systems. So far, MRR-based biosensors have been demonstrated mostly on polymer [5] and silicon-on-insulator (SOI) [10] photonic platforms due to the promise of the specific platforms for low-cost photonic integrated circuits (PICs fabricate MRRs on the TriPleX platform and to biochemically modify the surface of these MRRs and combine them with microfluidic elements was also demonstrated [11].…”

Modeling of Label-Free Optical Waveguide Biosensors with Surfaces Covered Partially by Vertically Homogeneous and Inhomogeneous Films

“…These techniques can also be combined with absorption spectroscopy [11][12][13]. Nowadays, these methods are well established and also available in highthroughput format [8,9,[14][15][16].…”

“…One drawback of the traditional OWLS technique is that it does not have imaging capabilities, like imaging ellipsometry, imaging SPR [15,16], or the recently introduced resonant waveguide gratings [8,14,23]. However, an important advantage of OWLS is that it can measure the effective refractive indices of two optical resonances, corresponding to the zeroth order transverse electric (TE) and transverse magnetic (TM) modes.…”

Sample handling in surface sensitive chemical and biological sensing: A practical review of basic fluidics and analyte transport

“…Biosensing technologies enabling label-free detection at a solid-liquid interface include surface plasmon resonance (SPR) (and SPR imaging, SPRi) [3,4,5], quartz crystal microbalance (QCM) [6], dual polarization interferometry (DPI) [7,8], grating-coupled interferometry (GCI) [9,10,11,12], the high-throughput compatible resonant waveguide grating biosensing [13,14,15], and optical waveguide lightmode spectroscopy (OWLS) [8,16,17,18]. OWLS instruments are currently among the most sensitive commercial label-free biosensors which enable the monitoring of various processes accompanied by refractive index changes 100-200 nm above a sensor surface .…”