Surface Generated Acoustic Wave Biosensors for the Detection of Pathogens: A Review

This review presents a deep insight into the Surface Generated Acoustic Wave (SGAW) technology for biosensing applications, based on more than 40 years of technological and scientific developments. In the last 20 years, SGAWs have been attracting the attention of the biochemical scientific community, due to the fact that some of these devices - Shear Horizontal Surface Acoustic Wave (SH-SAW), Surface Transverse Wave (STW), Love Wave (LW), Flexural Plate Wave (FPW), Shear Horizontal Acoustic Plate Mode (SH-APM) and Layered Guided Acoustic Plate Mode (LG-APM) - have demonstrated a high sensitivity in the detection of biorelevant molecules in liquid media. In addition, complementary efforts to improve the sensing films have been done during these years. All these developments have been made with the aim of achieving, in a future, a highly sensitive, low cost, small size, multi-channel, portable, reliable and commercially established SGAW biosensor. A setup with these features could significantly contribute to future developments in the health, food and environmental industries. The second purpose of this work is to describe the state-of-the-art of SGAW biosensors for the detection of pathogens, being this topic an issue of extremely importance for the human health. Finally, the review discuses the commercial availability, trends and future challenges of the SGAW biosensors for such applications

Réflexion sur l'introduction de l'enseignement des microsystèmes dans les différentes filières

Suite au démarrage de l'industrie des microsystèmes, se pose la question de savoir comment préparer les étudiants à travailler dans ce domaine. En France, différentes filières d'enseignement ont introduit depuis peu des enseignements sur les microsystèmes. Un bilan des différentes formations existant dans le domaine est présenté et l'exemple mené à Bordeaux concernant un enseignement théorique et une initiation à la CAO (conception assistée par ordinateur) des microsystèmes du premier au troisième cycle est exposé. Nous proposons quelques réflexions concernant l'apport de l'enseignement de cette nouvelle discipline que sont les microsystèmes et présentons les difficultés rencontrées

Surface Modifications of Love Acoustic Waves Sensors for Chemical and Biological Detection

International audienc

Acoustic, electrochemical and microscopic characterization of interaction of Arthrospira platensis biofilm and heavy metal ions

This study examines a biofilm of Arthrospira platensis and its interactions with cadmium and mercury, using electrochemical admittance spectroscopy technique combined with highly sensitive Love wave platform for the real-time detection in liquid medium. Spirulina cells were immobilized via multilayers of polyelectrolyte (PEM) on Si/SiO2 surface of both transducers and characterized using atomic force microscopy (AFM). Scanning electron microscopy (SEM) cell images revealed a first defense mechanism against cadmium at 10−12 M and it immediately takes place after 4 s from injection. The cyanobacteria biofilm becomes more conductive, due to an increase of polyphosphate bodies. An increase of density induces a decrease of frequency. Response time τ90% of the biofilm toward Cd2+ was between 6 and 8 min, while it did not exceed a few seconds toward Hg2+ at 10−12 M. However, the initial rapid stage of mercury adsorption took 40 s to reach the saturated stage. Once external sorption reached the saturated stage, internal mercury uptake began; cations were transported across the cell membrane into the cytoplasm and a beta-HgS precipitation took place, inducing conductivity biofilm decrease, and generating an increase of density, and thus a frequency decrease. SEM images revealed the beginning cell damage at 10−06 M of cadmium and mercury.Immunocapteur à ondes de Love ultra-sensible pour la détection rapide de micro-organismes dans l'eau, visant la réalisation d'un dispositif d'alert

Acoustic, electrochemical and microscopic characterization of interaction of Arthrospira platensis biofilm and heavy metal ions

This study examines a biofilm of Arthrospira platensis and its interactions with cadmium and mercury, using electrochemical admittance spectroscopy technique combined with highly sensitive Love wave platform for the real-time detection in liquid medium. Spirulina cells were immobilized via multilayers of polyelectrolyte (PEM) on Si/SiO2 surface of both transducers and characterized using atomic force microscopy (AFM). Scanning electron microscopy (SEM) cell images revealed a first defense mechanism against cadmium at 10−12 M and it immediately takes place after 4 s from injection. The cyanobacteria biofilm becomes more conductive, due to an increase of polyphosphate bodies. An increase of density induces a decrease of frequency. Response time τ90% of the biofilm toward Cd2+ was between 6 and 8 min, while it did not exceed a few seconds toward Hg2+ at 10−12 M. However, the initial rapid stage of mercury adsorption took 40 s to reach the saturated stage. Once external sorption reached the saturated stage, internal mercury uptake began; cations were transported across the cell membrane into the cytoplasm and a beta-HgS precipitation took place, inducing conductivity biofilm decrease, and generating an increase of density, and thus a frequency decrease. SEM images revealed the beginning cell damage at 10−06 M of cadmium and mercury.Immunocapteur à ondes de Love ultra-sensible pour la détection rapide de micro-organismes dans l'eau, visant la réalisation d'un dispositif d'alert