Szunerits S.,UniversiteLille 1 |
Shalabney A.,Ben - Gurion University of the Negev |
Boukherroub R.,UniversiteLille 1 |
Abdulhalim I.,Ben - Gurion University of the Negev |
Abdulhalim I.,Nanyang Technological University
Reviews in Analytical Chemistry | Year: 2012
Surface plasmon resonance (SPR) sensors have matured over the last 2 decades into very powerful tools for the study of biomolecular interactions, chemical detection and immunoassays. The performance of the sensor depends on several parameters, such as the choice of the metal thin fi lm where the plasmonic wave propagates, the excitation wavelength and the refractive index (RI) of the glass prism. Next to these physical parameters, the strategy selected to bind the desired receptors to the SPR chip, has a strong infl uence on the overall sensitivity and selectivity of the device. This review focuses on the advancement made using lamellar SPR structures, where a thin dielectric layer is deposited onto the surface plasmon active metal thin fi lm. Silver-based SPR interfaces can be developed using this approach, as these overlayers allow an effi cient protection of the underlying silver fi lm. At the same time, these interfaces open the scope for new surface functionalization schemes, which can be employed for anchoring ligands to the SPR sensor chip. While self-assembled monolayers (SAMs) are widely used, due to the possibility of easily incorporating carboxylate, amine or hydroxyl groups, the drawbacks of such fi lms include limited chemical and electrochemical stability. Moreover, a poor orientation and potential problems of protein adsorption and fouling, is often encountered if no synthetic effort in the synthesis of more sophisticated thiols is made. In addition, while the surface chemistry developed on gold has been of great value, the limitations of working on gold are becoming more noticeable, with increasingly complex fabrication requirements for biometric systems and arrays. Lamellar SPR interfaces represent an alternative route. Finally, the contribution of the thin dielectric top layer to the sensitivity of SPR sensors will be discussed. © 2012 by Walter de Gruyter.
Mysoet J.,Universitelille Nord Of France |
Mysoet J.,UniversiteLille 1 |
Canu M.-H.,Universitelille Nord Of France |
Canu M.-H.,UniversiteLille 1 |
And 6 more authors.
PLoS ONE | Year: 2014
A chronic reduction in neuromuscular activity through prolonged body immobilization in human alters motor task performance through a combination of peripheral and central factors. Studies performed in a rat model of sensorimotor restriction have shown functional and biochemical changes in sensorimotor cortex. However, the underlying mechanisms are still unclear. Interest was turned towards a possible implication of Insulin-like Growth Factor 1 (IGF-1), a growth factor known to mediate neuronal excitability and synaptic plasticity by inducing phosphorylation cascades which include the PI3K-AKT pathway. In order to better understand the influence of IGF-1 in cortical plasticity in rats submitted to a sensorimotor restriction, we analyzed the effect of hindlimb unloading on IGF-1 and its main molecular pathway in structures implied in motor control (sensorimotor cortex, striatum, cerebellum). IGF-1 level was determined by ELISA, and phosphorylation of its receptor and proteins of the PI3K-AKT pathway by immunoblot. In the sensorimotor cortex, our results indicate that HU induces a decrease in IGF-1 level; this alteration is associated to a decrease in activation of PI3K-AKT pathway. The same effect was observed in the striatum, although to a lower extent. No variation was noticed in the cerebellum. These results suggest that IGF-1 might contribute to cortical and striatal plasticity induced by a chronic sensorimotor restriction. © 2014 Mysoet et al.