Yves Moser - Profile on Academia.edu (original) (raw)

Papers by Yves Moser

Design and testing of the MOONS fibre positioning units

MOONS (Multi-Object Optical and Near-infrared Spectrograph) is a third-generation visible and nea... more MOONS (Multi-Object Optical and Near-infrared Spectrograph) is a third-generation visible and near-infrared spectrograph for the ESO Very Large Telescope currently under construction. The instrument’s spectroscopic capabilities are multiplexed via a fibre positioning module (FPM) which configures the location of 1001 fibres. The fibre positioning units (FPUs) have been jointly developed by the UK Astronomy Technology Centre (UKATC) and MPS Microsystems (MPS) to optimise instrument efficiency by providing excellent transmission and an open-loop positioning strategy, allowing a tightly packed focal plane to be rapidly reconfigured. The mechanism geometry enables all positions in the focal plane to be observed in conjunction with a companion sky fibre at close separation. A description of the as manufactured design and production process of the FPUs is presented, along with a discussion of the performance proven to date, including achievement of the critical pupil alignment and positio...

MOONS fibre positioning module: instrument build overview

Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation V

Magnetic particle dosing, release and separation in a microfluidic chip with magnetic actuation

TRANSDUCERS 2009 - 2009 International Solid-State Sensors, Actuators and Microsystems Conference, 2009

Separation of functionalized magnetic particles or magnetically-labeled entities is an important ... more Separation of functionalized magnetic particles or magnetically-labeled entities is an important tool in the field of bioanalysis. We present a novel integrated microfluidic magnetic bead separation device. On-chip manipulation of superparamagnetic beads is performed in a microfluidic channel under the influence of a highly focused magnetic field. Integrated magnetic microtips are used for retaining a defined amount of magnetic particles in a localized plug. This plug is released in a wellcontrolled way for subsequent particle separation with respect to their size and magnetic volume.

A quadrupolar magnetic actuation system for superparamagnetic particles

TRANSDUCERS 2009 - 2009 International Solid-State Sensors, Actuators and Microsystems Conference, 2009

We report on an innovative quadrupolar magnetic actuation system designed for performing immunoas... more We report on an innovative quadrupolar magnetic actuation system designed for performing immunoassays on-chip. Integrated magnetic microtips enable the retention and manipulation of functionalized superparamagnetic particles in a microfluidic channel. Actuation of dynamic bead plugs results in improved perfusion with sample solution thus enhanced analyte capture. The magnetic field parameters and kinetic properties of the bead plugs are discussed in detail. Improved protein capture efficiency is demonstrated with a model assay by means of fluorescent detection.

AIP Conference Proceedings, 2010

We present a method for magneto-microfluidic three-dimensional focusing of magnetic microparticle... more We present a method for magneto-microfluidic three-dimensional focusing of magnetic microparticles from a dense plug into a single streamline with longitudinal inter-particle spacing. Plug formation on-chip is induced by a highgradient magnetic field generated at the sidewall of a microchannel by an integrated micromachined magnetic tip that is connected to an external electromagnet. Controlled release of the microparticles is achieved using an exponential damping protocol of the magnetic retention force in the presence of an applied flow.

Three-dimensional hydro-magnetic focusing and in-flow separation of superparamagnetic beads

Sensors and Actuators B: Chemical, 2011

Separation of functional magnetic particles or magnetically labeled entities is a key feature for... more Separation of functional magnetic particles or magnetically labeled entities is a key feature for bioanalytical or biomedical applications and therefore also an important component of lab-on-a-chip devices for biological applications. We present a novel integrated microfluidic magnetic bead manipulation device, comprising dosing of magnetic particles, controlled release and subsequent magnetophoretic size separation with high resolution. The system is designed to meet the requirements of specific bioassays, in particular of on-chip agglutination assays for the detection of rare analytes by particle coupling as doublets. Integrated soft-magnetic microtips with different shapes provide the magnetic driving force of the bead manipulation protocol. The magnetic tips that serve as field concentrators of an external electromagnetic field, are positioned in close contact to a microfluidic channel in order to generate high magnetic actuation forces. Mixtures of 1.0 m and 2.8 m superparamagnetic beads have been used to characterize the system. Magnetophoretic size separation with high resolution was performed in static conditions and in continuous flow mode. In particular, we could demonstrate the separation of 1.0 m single beads and doublets in a sample flow.

Miniaturized Flexible Temperature Sensor

Journal of Microelectromechanical Systems, 2007

We realize a flexible temperature sensor based on a micropatterned thin-film platinum resistor. T... more We realize a flexible temperature sensor based on a micropatterned thin-film platinum resistor. The sensor is situated at the end of a 100-mum-wide and 7-cm-long probe. The latter consists of a biocompatible high-temperature-resistant polyimide (U-Varnish-S, UBE Industries, Tokyo, Japan) in which the platinum resistor and the electrical contact leads are embedded. The sensor is operational from 0degC up to 400degC

Analytical Chemistry, 2011

This thesis was carried out in the frame of the European project DetectHIV aiming the development... more This thesis was carried out in the frame of the European project DetectHIV aiming the development of a new biosensor platform for the highly sensitive detection of the HIV capsid protein p24. We explore the implementation of a magnetic bead-based lab-on-a-chip system, offering significant advantages compared to conventional systems, mainly through the possibility of controlled manipulation of the magnetic carriers on-chip. In particular, microfluidic immunoassays using functionalized magnetic beads raise increasing interest. In this thesis, we present a microsystem for the magnetic manipulation of superparamagnetic beads on-chip. A highly confined and dynamically actuated plug of biochemically functionalized beads is formed in a microchannel. This plug extends over the channel cross-section, thus allowing efficient analyte capture from the flow. Subsequent immobilization of the plug for incubation modifies the colloidal state (agglutination test). Dynamic actuation of beads is enabled by superposing a static magnetic field and a time-varying magnetic field. The latter field is highly focused and concentrated across the microchannel by means of soft magnetic microtips. A new method for the fabrication of rigid monolithic SU-8 microchannels allows control and ready mechanical integration of the microtips with the microfluidic structure. A protocol for performing magnetic bead-based immuno-agglutination assays on-chip using our system was developed. A simple detection method based on the swelling of the released plug after agglutination is presented. We demonstrate the feasibility of on-chip agglutination tests by means of a streptavidin/biotinylated-bovine serum albumin (bBSA) model assay. A detection limit of about 200 pg/mL (3 pM) was obtained. Furthermore, the potential of the magnetic actuation method was emphasized by implementing a heterogeneous immunoassay with a dendritic amplification mechanism. Dendritic amplification aims to increase the detection sensitivity. Amplification of the detection signal is achieved by alternating exposure of the beads to a flow of fluorescently labeled streptavidin molecules and biotin conjugated anti-streptavidin, respectively. The magnetic system developed in the frame of this thesis was integrated in the final biosensor platform of the DetectHIV project. This platform comprises an integrated chip cartridge with an optical detection module. This design is outlined in the last part of the thesis.

Suspended SU-8 structures for monolithic microfluidic channels

Microfluidics and Nanofluidics, 2011

On-chip immuno-agglutination assay with analyte capture by dynamic manipulation of superparamagnetic beads

Lab on a Chip, 2009

Magnetic bead-based lab-on-a-chip systems offer significant advantages compared to more conventio... more Magnetic bead-based lab-on-a-chip systems offer significant advantages compared to more conventional systems, mainly through the possibility of controlled manipulation of the magnetic carriers on-chip. In particular, microfluidic immunoassays using functionalized magnetic beads raise increasing interest. We present here a new approach for performing immuno-agglutination assays on-chip. Our system is based on a quadrupolar magnetic field set-up. Dynamic actuation of a confined plug of functionalized magnetic beads is used for analyte capture in a microchannel. A simple detection method based on the swelling of the released plug after agglutination is presented. We demonstrate the feasibility of on-chip agglutination tests by means of a streptavidin/biotinylated-bovine serum albumin (bBSA) model assay. A detection limit of about 200 pg/mL (approximately 3 pM) is achieved.

Applied Physics Letters, 2009

We report on the magnetic actuation of superparamagnetic particles in a microfluidic channel. The... more We report on the magnetic actuation of superparamagnetic particles in a microfluidic channel. The formation of a highly confined and dynamic plug of particles extending over the cross section of the microchannel is enabled by superposing a static and a time-varying magnetic field. The latter is generated by an electromagnet and focused across the microchannel using microstructured soft magnetic tips.

Design and testing of the MOONS fibre positioning units

MOONS (Multi-Object Optical and Near-infrared Spectrograph) is a third-generation visible and nea... more MOONS (Multi-Object Optical and Near-infrared Spectrograph) is a third-generation visible and near-infrared spectrograph for the ESO Very Large Telescope currently under construction. The instrument’s spectroscopic capabilities are multiplexed via a fibre positioning module (FPM) which configures the location of 1001 fibres. The fibre positioning units (FPUs) have been jointly developed by the UK Astronomy Technology Centre (UKATC) and MPS Microsystems (MPS) to optimise instrument efficiency by providing excellent transmission and an open-loop positioning strategy, allowing a tightly packed focal plane to be rapidly reconfigured. The mechanism geometry enables all positions in the focal plane to be observed in conjunction with a companion sky fibre at close separation. A description of the as manufactured design and production process of the FPUs is presented, along with a discussion of the performance proven to date, including achievement of the critical pupil alignment and positio...

MOONS fibre positioning module: instrument build overview

Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation V

Magnetic particle dosing, release and separation in a microfluidic chip with magnetic actuation

TRANSDUCERS 2009 - 2009 International Solid-State Sensors, Actuators and Microsystems Conference, 2009

Separation of functionalized magnetic particles or magnetically-labeled entities is an important ... more Separation of functionalized magnetic particles or magnetically-labeled entities is an important tool in the field of bioanalysis. We present a novel integrated microfluidic magnetic bead separation device. On-chip manipulation of superparamagnetic beads is performed in a microfluidic channel under the influence of a highly focused magnetic field. Integrated magnetic microtips are used for retaining a defined amount of magnetic particles in a localized plug. This plug is released in a wellcontrolled way for subsequent particle separation with respect to their size and magnetic volume.

A quadrupolar magnetic actuation system for superparamagnetic particles

TRANSDUCERS 2009 - 2009 International Solid-State Sensors, Actuators and Microsystems Conference, 2009

We report on an innovative quadrupolar magnetic actuation system designed for performing immunoas... more We report on an innovative quadrupolar magnetic actuation system designed for performing immunoassays on-chip. Integrated magnetic microtips enable the retention and manipulation of functionalized superparamagnetic particles in a microfluidic channel. Actuation of dynamic bead plugs results in improved perfusion with sample solution thus enhanced analyte capture. The magnetic field parameters and kinetic properties of the bead plugs are discussed in detail. Improved protein capture efficiency is demonstrated with a model assay by means of fluorescent detection.

AIP Conference Proceedings, 2010

We present a method for magneto-microfluidic three-dimensional focusing of magnetic microparticle... more We present a method for magneto-microfluidic three-dimensional focusing of magnetic microparticles from a dense plug into a single streamline with longitudinal inter-particle spacing. Plug formation on-chip is induced by a highgradient magnetic field generated at the sidewall of a microchannel by an integrated micromachined magnetic tip that is connected to an external electromagnet. Controlled release of the microparticles is achieved using an exponential damping protocol of the magnetic retention force in the presence of an applied flow.

Three-dimensional hydro-magnetic focusing and in-flow separation of superparamagnetic beads

Sensors and Actuators B: Chemical, 2011

Separation of functional magnetic particles or magnetically labeled entities is a key feature for... more Separation of functional magnetic particles or magnetically labeled entities is a key feature for bioanalytical or biomedical applications and therefore also an important component of lab-on-a-chip devices for biological applications. We present a novel integrated microfluidic magnetic bead manipulation device, comprising dosing of magnetic particles, controlled release and subsequent magnetophoretic size separation with high resolution. The system is designed to meet the requirements of specific bioassays, in particular of on-chip agglutination assays for the detection of rare analytes by particle coupling as doublets. Integrated soft-magnetic microtips with different shapes provide the magnetic driving force of the bead manipulation protocol. The magnetic tips that serve as field concentrators of an external electromagnetic field, are positioned in close contact to a microfluidic channel in order to generate high magnetic actuation forces. Mixtures of 1.0 m and 2.8 m superparamagnetic beads have been used to characterize the system. Magnetophoretic size separation with high resolution was performed in static conditions and in continuous flow mode. In particular, we could demonstrate the separation of 1.0 m single beads and doublets in a sample flow.

Miniaturized Flexible Temperature Sensor

Journal of Microelectromechanical Systems, 2007

We realize a flexible temperature sensor based on a micropatterned thin-film platinum resistor. T... more We realize a flexible temperature sensor based on a micropatterned thin-film platinum resistor. The sensor is situated at the end of a 100-mum-wide and 7-cm-long probe. The latter consists of a biocompatible high-temperature-resistant polyimide (U-Varnish-S, UBE Industries, Tokyo, Japan) in which the platinum resistor and the electrical contact leads are embedded. The sensor is operational from 0degC up to 400degC

Analytical Chemistry, 2011

This thesis was carried out in the frame of the European project DetectHIV aiming the development... more This thesis was carried out in the frame of the European project DetectHIV aiming the development of a new biosensor platform for the highly sensitive detection of the HIV capsid protein p24. We explore the implementation of a magnetic bead-based lab-on-a-chip system, offering significant advantages compared to conventional systems, mainly through the possibility of controlled manipulation of the magnetic carriers on-chip. In particular, microfluidic immunoassays using functionalized magnetic beads raise increasing interest. In this thesis, we present a microsystem for the magnetic manipulation of superparamagnetic beads on-chip. A highly confined and dynamically actuated plug of biochemically functionalized beads is formed in a microchannel. This plug extends over the channel cross-section, thus allowing efficient analyte capture from the flow. Subsequent immobilization of the plug for incubation modifies the colloidal state (agglutination test). Dynamic actuation of beads is enabled by superposing a static magnetic field and a time-varying magnetic field. The latter field is highly focused and concentrated across the microchannel by means of soft magnetic microtips. A new method for the fabrication of rigid monolithic SU-8 microchannels allows control and ready mechanical integration of the microtips with the microfluidic structure. A protocol for performing magnetic bead-based immuno-agglutination assays on-chip using our system was developed. A simple detection method based on the swelling of the released plug after agglutination is presented. We demonstrate the feasibility of on-chip agglutination tests by means of a streptavidin/biotinylated-bovine serum albumin (bBSA) model assay. A detection limit of about 200 pg/mL (3 pM) was obtained. Furthermore, the potential of the magnetic actuation method was emphasized by implementing a heterogeneous immunoassay with a dendritic amplification mechanism. Dendritic amplification aims to increase the detection sensitivity. Amplification of the detection signal is achieved by alternating exposure of the beads to a flow of fluorescently labeled streptavidin molecules and biotin conjugated anti-streptavidin, respectively. The magnetic system developed in the frame of this thesis was integrated in the final biosensor platform of the DetectHIV project. This platform comprises an integrated chip cartridge with an optical detection module. This design is outlined in the last part of the thesis.

Suspended SU-8 structures for monolithic microfluidic channels

Microfluidics and Nanofluidics, 2011

On-chip immuno-agglutination assay with analyte capture by dynamic manipulation of superparamagnetic beads

Lab on a Chip, 2009

Magnetic bead-based lab-on-a-chip systems offer significant advantages compared to more conventio... more Magnetic bead-based lab-on-a-chip systems offer significant advantages compared to more conventional systems, mainly through the possibility of controlled manipulation of the magnetic carriers on-chip. In particular, microfluidic immunoassays using functionalized magnetic beads raise increasing interest. We present here a new approach for performing immuno-agglutination assays on-chip. Our system is based on a quadrupolar magnetic field set-up. Dynamic actuation of a confined plug of functionalized magnetic beads is used for analyte capture in a microchannel. A simple detection method based on the swelling of the released plug after agglutination is presented. We demonstrate the feasibility of on-chip agglutination tests by means of a streptavidin/biotinylated-bovine serum albumin (bBSA) model assay. A detection limit of about 200 pg/mL (approximately 3 pM) is achieved.

Applied Physics Letters, 2009

We report on the magnetic actuation of superparamagnetic particles in a microfluidic channel. The... more We report on the magnetic actuation of superparamagnetic particles in a microfluidic channel. The formation of a highly confined and dynamic plug of particles extending over the cross section of the microchannel is enabled by superposing a static and a time-varying magnetic field. The latter is generated by an electromagnet and focused across the microchannel using microstructured soft magnetic tips.