Optical Index Prism Sensitivity of Surface Plasmon Resonance Imaging in Gas Phase: Experiment versus Theory

Abstract

Recent advances in SPR-imaging detection in gas phase have led to the development of opto-electronic noses (opto-eNs) requiring the need for optical sensitivity characterization of such devices. Understanding of the optical contributions will have an implicit relevance on sensitivity enhancement of SPR-imaging in gas phase valuable to improve the performance of opto-eN and potentially open new applications as gas sensors. In this paper, we analyzed the optical contributions to the sensitivity of the SPR imaging prisms and potential insights into their contributing factors. We established a characterization method for the SPR prism sensitivity that is independent of the carrier gas considered. Then, by using this sensitivity parameter, the influence of two different kinds of adhesive layers, Cr and Ti, of the gold coated prisms were studied. Furthermore, we considered a theoretical model to rationalize our experimental results, which demonstrated the relevance of surface topography on the optical index 1 sensitivity. Those surface topographies were characterized experimentally and were implemented in the model free from any additional fitting parameters using a modified Maxwell-Garnet theory. Finally, the model was shown to predictively assess the experimentally measured effects of temperature on the prism sensitivity.

Enhancing the Sensitivity of Surface Plasmon Resonance Measurements Utilizing Polymer Film/Au Assemblies

“…A recent study by Weerakkody et al. used Maxwell Garnet mixing theory to generate an anisotropic effective permittivity that accounts for the effects of surface topology within a transfer matrix model . However, the mixing formula was derived assuming ellipsoidal inclusions .…”

“…A recent study by Weerakkody et al used Maxwell Garnet mixing theory to generate an anisotropic effective permittivity that accounts for the effects of surface topology within a transfer matrix model. 40 However, the mixing formula was derived assuming ellipsoidal inclusions. 41 For sparsely distributed microgels with a hemispherical profile and gold islands that follow the topology of the microgel surface, this ellipsoidal approximation is not accurate.…”

An Overview of Artificial Olfaction Systems with a Focus on Surface Plasmon Resonance for the Analysis of Volatile Organic Compounds

“…These systems were limited in terms of sensitivity and selectivity based on only one or few sensitive chemical layers. Since 2000, an increasing number of articles can be found in the literature using both biological and organic sensitive materials [185][186][187][188][189][190][191][192][193][194][195][196][197][198][199][200][201][202][203][204]. It has been demonstrated that SPR is very effective for sensing VOCs in the gas phase.…”

“…Furthermore, we investigated the optical contributions to the sensitivity of the SPR imaging [187]. For this, an original characterization method, which was independent of the carrier gas, was established for the SPR prism sensitivity based on pressure jumps [205].…”

Peptides, DNA and MIPs in Gas Sensing. From the Realization of the Sensors to Sample Analysis

“…One of the attractive features of peptides is the possibility to obtain a particular binding ability designing a sequence by molecular modeling. Using this concept and starting from a sequence in the P 30953 receptor protein (Swiss prot G databank) in 2011, Sankaran et al [ 67 ] obtained the synthetic peptide Ps17 designed for alcohols. Ps17 was immobilized onto 10 MHz QCMs by SAM and tested with hexanol and pentanol.…”