Polymer resonators sensors for detection of sphingolipid gel/fluid phase transition and melting temperature measurement

Abstract

This work describes a low-cost biophotonic sensor shaped by way of cheap processes as hybrid silicon/silica/polymer resonators able to detect biological molecule gel/fluid phase transition as lipids at very low concentration (sphingomyelin). The photonic structure is composed of specific amplified deep UV photoresist-polymer waveguides coupled by a sub-wavelength gap with racetrack microresonators allowing a low temperature-dependent operation ranging from 16 to 42 °C. The temperature dependent wavelength shift and the thermo-optic coefficient characterizing the quantified resonances and opto-geometric properties of the device have been evaluated, highlighting an enough low thermal features of the whole system for such application. With an appropriate vesicle lipid deposition process specific in biology associated to an apt experimental bio-thermo-photonic protocol (made of serial optical resonance spectra acquisitions with statistical treatments), the dynamic evolution of the sphingomyelin lipid phase transition was assessed: then, the ability to detect their own gel/fluid transition phase and melting temperature has been demonstrated with a mass product factor 10 7 lower than that of more conventional methods. The equilibrium of the regime of the resonators was highlighted as being broken by the dynamic of the sphingomyelin and its own phase transition prior relevant detection.

Microphotonics for monitoring the supramolecular thermoresponsive behavior of fatty acid surfactant solutions

“…[16]. On such devices, the thermal dependences of the main optical properties at the Si/SiO 2 /UV210/air configuration were presented, and it was concluded that the thermo-optical properties of the IO microresonator based on UV210 polymer have a high quality, verifying its high thermal stability [16]. Fig.…”

“…From previous studies focused on the detection of gel/fluid phase transition of biological compounds using polymeric microcavity, an extended experimental and computing protocol were presented in ref. [16]. On such devices, the thermal dependences of the main optical properties at the Si/SiO 2 /UV210/air configuration were presented, and it was concluded that the thermo-optical properties of the IO microresonator based on UV210 polymer have a high quality, verifying its high thermal stability [16].…”

“…On the other hand, in the second one, any cladding variation induces a change that can be detected by the resonator over the background signal. This cladding variation will induce a change in the effective refractive index n eff [12,13,16,17]. For the scope of this work, we will focused on the second sensing mechanism: the homogeneous sensing.…”

About monitoring the dynamics of phase transition in food and biology by micro-photonics: detecting soft-matter process

“…The fabrication of the structures is detailed. The experimental setup is presented and then relevant results on fatty acid [9] (cosmetic, food) and sphingomyelin [10] (biology) phase transitions are exposed and discussed.…”

Photonic micro-resonators for steam evaporation dynamic sensing

“…As miniaturizable and most accurate, photonic micro-resonator sensors come up as very efficient in following small-scale phenomena or in detecting sparsely concentrated chemical species [11]. These characteristics are most interesting for both environmental monitoring [12] and biology together with biomedical or biophysics [13] fundamental research (among other fields). However, with a large majority of scientific works using integrated micro-resonator sensors focusing on static phenomena [9,[11][12][13], most often the transduced signal of the photonic structure is monitored against concentration values of given species or versus temperature.…”