Guillaume Nonglaton - Academia.edu (original) (raw)

Papers by Guillaume Nonglaton

The first Very Large Scale Integration process with variable shape beam lithography for optomecha... more The first Very Large Scale Integration process with variable shape beam lithography for optomechanical devices is presented. State of the art performance was obtained with silicon microdisk resonators showing 1 million optical quality factors and 10−17m.Hz(−1/2) displacement resolution. Single-particle mass spectrometry could be performed with these optomechanical resonators in vacuum. The devices retained high performance when directly immersed in liquid media, allowing for biosensing experiments. These results open the door to large, dense arrays of optomechanical sensors.

The present invention relates to a method of forming a shape defined and localized deposition of ... more The present invention relates to a method of forming a shape defined and localized deposition of a material on the surface of a substrate comprising the steps of (1) delimit, by photolithography at the surface of said substrate, at least one localized site and of defined shape, wettable with a solution containing said material or from which said material is obtained, defining the areas surrounding and including said site being non-wettable by said solution; (2) depositing, on said site and said zones, said solution; whereby said material is deposited at said site.

Biotechnology Journal

In recent years, many biocatalytic processes have been developed for the production of chemicals ... more In recent years, many biocatalytic processes have been developed for the production of chemicals and pharmaceuticals. In this context, enzyme immobilization methods have attracted attention for their advantages, such as continuous production and increased stability. Here, enzyme immobilization methods and a collection of nitrilases from biodiversity for the conversion of 3‐cyanopyridine to nicotinic acid were screened. Substrate conversion over 10 conversion cycles was monitored to optimize the process. The best immobilization conditions were found with cross‐linking using glutaraldehyde to modify the PMMA beads. This method showed good activity over 10 cycles in a batch reactor at 30 and 40°C. Finally, production with a new thermostable nitrilase was examined in a continuous packed bed reactor, showing very high stability of the biocatalytic process at a flow rate of 0.12 ml min–1 and a temperature of 50°C. The complete conversion of 3‐cyanopyridine was obtained over 30 days of operation. Future steps will concern reactor scale‐up to increase the production rate with reasonable pressure drops.

ACS Applied Bio Materials

npj Microgravity

Future long-duration human spaceflight calls for developments to limit biocontamination of the su... more Future long-duration human spaceflight calls for developments to limit biocontamination of the surface habitats. The MATISS experiment tests surface treatments in the ISS’s atmosphere. Four sample holders were mounted with glass lamella with hydrophobic coatings, and exposed in the Columbus module for ~6 months. About 7800 particles were detected by tile scanning optical microscopy (×3 and ×30 magnification) indicating a relatively clean environment (a few particles per mm2), but leading to a significant coverage-rate (>2% in 20 years). Varied shapes were displayed in the coarse (50–1500 µm2) and fine (0.5–50 µm2) area fractions, consistent with scale dices (tissue or skin) and microbial cells, respectively. The 200–900 µm2 fraction of the coarse particles was systematically higher on FDTS and SiOCH than on Parylene, while the opposite was observed for the <10 µm2 fraction of the fine particles. This trend suggests two biocontamination sources and a surface deposition impacted...

ACS Applied Bio Materials

HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Carbohydrate Polymers

In this paper, strictly speaking aerogels of cellulose nanofibrils (CNFs) and TEMPO-oxidized CNFs... more In this paper, strictly speaking aerogels of cellulose nanofibrils (CNFs) and TEMPO-oxidized CNFs (TO-CNFs) were obtained from an optimized supercritical drying processes and cryogels were prepared after freeze-drying. The cryogels and aerogels were characterized and the influence of the preparation process on the resulting properties was studied. Significant differences were observed in the micro- and nanoscale organization of the porous structures. In addition, the specific surface areas measured varied from 25 to 160 m² g-1 for CNF materials, depending on the preparation process. Very high specific surface areas up to 482 m² g-1 among the highest reported for pure cellulose nanofibrils porous materials were achieved for TO-CNF aerogels. Finally, in order to evaluate their aptitudes for wound dressings applications, the capillary water uptake capacities were assessed on skin mimicking layers. From this study, it was revealed that TO-CNF aerogels can absorb almost 120 times their own weight of water.

Materials Science and Engineering: C

The natural biodegradabilty of porous silicon (pSi) in physiological media limits its wider usage... more The natural biodegradabilty of porous silicon (pSi) in physiological media limits its wider usage for implantable systems. We report the stabilization of porous silicon (pSi) membranes by chemical surface oxidation using RCA1 and RCA2 protocols, which was followed by a PEGylation process using a silane-PEG. These surface modifications stabilized the pSi to allow a long period of immersion in PBS, while leaving the pSi surface sufficiently hydrophilic for good filtration and diffusion of several biomolecules of different sizes without any blockage of the pSi structure. The pore sizes of the pSi membranes were between 5 and 20 nm, with the membrane thickness around 70 μm. The diffusion coefficient for fluorescein through the membrane was 2 × 10-10 cm2 s-1, and for glucose was 2.2 × 10-9 cm2 s-1. The pSi membrane maintained that level of glucose diffusion for one month of immersion in PBS. After 2 months immersion in PBS the pSi membrane continued to operate, but with a reduced glucose diffusion coefficient. The chemical stabilization of pSi membranes provided almost 1 week stable and functional biomolecule transport in blood plasma and opens the possibility for its short-term implantation as a diffusion membrane in biocompatible systems.

Cellulose

High aspect ratio cellulose nanocrystals (CNCs) extracted from tunicate were used to create so-ca... more High aspect ratio cellulose nanocrystals (CNCs) extracted from tunicate were used to create so-called cryogels from an ice-templating directional freeze-drying process. The structure of the resulting solid foam was investigated at the micro- and nanoscales by scanning electron microscopy and nitrogen adsorption measurements were used to extract the specific surface area. The mechanical properties were probed by compression tests. To highlight the specificities of tunicate CNC-based cryogels, results were compared with the one obtained from two other types of nanocellulose, namely cellulose nanofibrils (CNFs) from wood and CNCs from cotton, which exhibit different dimensions, aspect ratio, flexibility and crystallinity. While CNF- and cotton CNC-based cryogels exhibited a classical morphology characterized by a sheet-like structure, a particular honeycomb organization with individual particles was obtained in the case of tunicate CNC cryogels. The latter cryogels presented a very high specific surface area of about 122 m 2 g −1 , which is unexpected for foams prepared from a water-based process and much higher than what was obtained for CNF and cotton CNC cryogels (25 and 4 m 2 g −1 , respectively). High mechanical resistance and stiffness were also obtained with such tunicate CNC cryogels. These results are explained by the high crystallinity, aspect ratio and rigidity of the tunicate CNCs combined with the particular honeycomb architecture of the cryogel.

Chemical Science

Hydrogen production through direct sunlight-driven water splitting in Photo-Electrochemical Cells... more Hydrogen production through direct sunlight-driven water splitting in Photo-Electrochemical Cells (PECs) is a promising solution for energy sourcing. PECs need to respond to three criteria: sustainability, cost-effectiveness and stability. Here...

Small

Metallic conductive nanowires (NWs) with DNA bundle core are achieved, thanks to an original proc... more Metallic conductive nanowires (NWs) with DNA bundle core are achieved, thanks to an original process relying on double-stranded DNA alignment and physical vapor deposition (PVD) metallization steps involving a silicon substrate. First, bundles of DNA are suspended with a repeatable process between 2 µm high parallel electrodes with separating gaps ranging from 800 nm to 2 µm. The process consists in the drop deposition of a DNA lambda-phage solution on the electrodes followed by a naturally evaporation step. The deposition process is controlled by the DNA concentration within the buffer solution, the drop volume, and the electrode hydrophobicity. The suspended bundles are finally metallized with various thicknesses of titanium and gold by a PVD e-beam evaporation process. The achieved NWs have a width ranging from a few nanometers up to 100 nm. The electrical behavior of the achieved 60 and 80 nm width metallic NWs is shown to be Ohmic and their intrinsic resistance is estimated according to different geometrical models of the NW section area. For the 80 nm width NWs, a resistance of about few ohms is established, opening exploration fields for applications in microelectronics.

The Analyst, Jan 24, 2016

DNA is under continuous assault by environmental and endogenous reactive oxygen and alkylating sp... more DNA is under continuous assault by environmental and endogenous reactive oxygen and alkylating species, inducing the formation of mutagenic, toxic and genome destabilizing nucleobase lesions. Due to the implications of such genetic alterations in cell death, aging, inflammation, neurodegenerative diseases and cancer, many efforts have been devoted to developing assays that aim at analyzing DNA repair activities from purified enzymes or cell extracts. The present work deals with the conception and application of a new, miniaturized and parallelized on surface-DNA biosensor to measure base excision repair (BER) activities. Such a bio-analytical tool was built by using the "click chemistry" approach to immobilize, on a glass slide, fluorescent stem-loop DNA probes, which contain a specific nucleobase lesion. The performance of this new high-throughput DNA repair analysis technology was determined by detecting uracil N-glycosylase and AP-endonuclease activities from purified e...

A novel concept for protein recognition has been developed. The recognition unit is a hybrid mole... more A novel concept for protein recognition has been developed. The recognition unit is a hybrid molecule obtained by conjugation of a small organic molecule to a synthetic polypeptide selected from a 16-membered set of 42 amino acid residue sequences. The sequences are unordered and have no prior relation to the target proteins. The concept is based on the hypothesis that a small set of sequences capable of hydrophobic interactions, hydrogen bonding and electrostatic interactions can yield a binder for any selected protein, provided that the small molecule shows medium affinity or better and is reasonably selective. The concept has been illustrated by the design, synthesis and evaluation of binders for three different proteins, the C-reactive protein, CRP, human Carbonic anhydrase II, HCAII, and Acetylcholine esterase, AChE. Highly efficient binders for CRP have been developed by conjugation of a derivative of the natural ligand, phosphocholine, to the side chain of one of the amino acids in each polypeptide. The binders in the set show a wide range of affinities for CRP and the tightest binder, 4-C10L17-PC6, binds almost irreversibly. Selected binders have been evaluated in human serum, where they capture CRP with high selectivity.High-affinity binders have been developed for HCAII, and the selectivity evaluated by extraction of the protein from blood. The binder 4-C37L34-B, a polypeptide conjugated to a spacered benzenesulphonamide residue, was able to extract Carbonic anhydrases specifically and to discriminate between the two isoforms of human Carbonic anhydrase. The conjugation of an acridine derivative to a polypeptide via a 14 atom spacer has been shown to yield a binder with high affinity and selectivity for AChE. The selectivity was demonstrated by extraction of AChE from Cerebrospinal fluid. This thesis focuses on the development of a fast and reliable procedure for the construction, selection and evaluation of protein binders, with the ambition to develop a technology that is applicable to the development of binders for all proteins.

Http Www Theses Fr, 2005

This report deals with a new process for preparing DNA microarrays using glass slides covered by ... more This report deals with a new process for preparing DNA microarrays using glass slides covered by a zirconium phosphonate monolayer deposited by Langmuir-Blodgett method. Oligonucleotides probes modified with a terminal phosphate were spotted onto the zirconated surface where they bound by formation of metal-oxygen covalent bonds. Performances of this new type of DNA microarrays were studied in biological conditions. An increase of the fluorescence intensity was observed when using a polyguanine spacer between the probe oligomer and the terminal phosphate. Then the synthesis of novel chiral P,N-ligands by desymmetrization of the achiral meso N,N'-dimethyl-1,2-diphenylethane-1,2-diamine backbone is described. This transformation was achieved by the selective introduction of a diphenylphosphine moiety on one of the two nitrogen centers. The coordination of this ligand (L) with Rh(I) and Pd(0) precursors led to the formation of complexes which can be of potential interest for catalysis.

Microfluidics and Nanofluidics, 2014

The first Very Large Scale Integration process with variable shape beam lithography for optomecha... more The first Very Large Scale Integration process with variable shape beam lithography for optomechanical devices is presented. State of the art performance was obtained with silicon microdisk resonators showing 1 million optical quality factors and 10−17m.Hz(−1/2) displacement resolution. Single-particle mass spectrometry could be performed with these optomechanical resonators in vacuum. The devices retained high performance when directly immersed in liquid media, allowing for biosensing experiments. These results open the door to large, dense arrays of optomechanical sensors.

The present invention relates to a method of forming a shape defined and localized deposition of ... more The present invention relates to a method of forming a shape defined and localized deposition of a material on the surface of a substrate comprising the steps of (1) delimit, by photolithography at the surface of said substrate, at least one localized site and of defined shape, wettable with a solution containing said material or from which said material is obtained, defining the areas surrounding and including said site being non-wettable by said solution; (2) depositing, on said site and said zones, said solution; whereby said material is deposited at said site.

Biotechnology Journal

In recent years, many biocatalytic processes have been developed for the production of chemicals ... more In recent years, many biocatalytic processes have been developed for the production of chemicals and pharmaceuticals. In this context, enzyme immobilization methods have attracted attention for their advantages, such as continuous production and increased stability. Here, enzyme immobilization methods and a collection of nitrilases from biodiversity for the conversion of 3‐cyanopyridine to nicotinic acid were screened. Substrate conversion over 10 conversion cycles was monitored to optimize the process. The best immobilization conditions were found with cross‐linking using glutaraldehyde to modify the PMMA beads. This method showed good activity over 10 cycles in a batch reactor at 30 and 40°C. Finally, production with a new thermostable nitrilase was examined in a continuous packed bed reactor, showing very high stability of the biocatalytic process at a flow rate of 0.12 ml min–1 and a temperature of 50°C. The complete conversion of 3‐cyanopyridine was obtained over 30 days of operation. Future steps will concern reactor scale‐up to increase the production rate with reasonable pressure drops.

ACS Applied Bio Materials

npj Microgravity

Future long-duration human spaceflight calls for developments to limit biocontamination of the su... more Future long-duration human spaceflight calls for developments to limit biocontamination of the surface habitats. The MATISS experiment tests surface treatments in the ISS’s atmosphere. Four sample holders were mounted with glass lamella with hydrophobic coatings, and exposed in the Columbus module for ~6 months. About 7800 particles were detected by tile scanning optical microscopy (×3 and ×30 magnification) indicating a relatively clean environment (a few particles per mm2), but leading to a significant coverage-rate (>2% in 20 years). Varied shapes were displayed in the coarse (50–1500 µm2) and fine (0.5–50 µm2) area fractions, consistent with scale dices (tissue or skin) and microbial cells, respectively. The 200–900 µm2 fraction of the coarse particles was systematically higher on FDTS and SiOCH than on Parylene, while the opposite was observed for the <10 µm2 fraction of the fine particles. This trend suggests two biocontamination sources and a surface deposition impacted...

ACS Applied Bio Materials

HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Carbohydrate Polymers

In this paper, strictly speaking aerogels of cellulose nanofibrils (CNFs) and TEMPO-oxidized CNFs... more In this paper, strictly speaking aerogels of cellulose nanofibrils (CNFs) and TEMPO-oxidized CNFs (TO-CNFs) were obtained from an optimized supercritical drying processes and cryogels were prepared after freeze-drying. The cryogels and aerogels were characterized and the influence of the preparation process on the resulting properties was studied. Significant differences were observed in the micro- and nanoscale organization of the porous structures. In addition, the specific surface areas measured varied from 25 to 160 m² g-1 for CNF materials, depending on the preparation process. Very high specific surface areas up to 482 m² g-1 among the highest reported for pure cellulose nanofibrils porous materials were achieved for TO-CNF aerogels. Finally, in order to evaluate their aptitudes for wound dressings applications, the capillary water uptake capacities were assessed on skin mimicking layers. From this study, it was revealed that TO-CNF aerogels can absorb almost 120 times their own weight of water.

Materials Science and Engineering: C

The natural biodegradabilty of porous silicon (pSi) in physiological media limits its wider usage... more The natural biodegradabilty of porous silicon (pSi) in physiological media limits its wider usage for implantable systems. We report the stabilization of porous silicon (pSi) membranes by chemical surface oxidation using RCA1 and RCA2 protocols, which was followed by a PEGylation process using a silane-PEG. These surface modifications stabilized the pSi to allow a long period of immersion in PBS, while leaving the pSi surface sufficiently hydrophilic for good filtration and diffusion of several biomolecules of different sizes without any blockage of the pSi structure. The pore sizes of the pSi membranes were between 5 and 20 nm, with the membrane thickness around 70 μm. The diffusion coefficient for fluorescein through the membrane was 2 × 10-10 cm2 s-1, and for glucose was 2.2 × 10-9 cm2 s-1. The pSi membrane maintained that level of glucose diffusion for one month of immersion in PBS. After 2 months immersion in PBS the pSi membrane continued to operate, but with a reduced glucose diffusion coefficient. The chemical stabilization of pSi membranes provided almost 1 week stable and functional biomolecule transport in blood plasma and opens the possibility for its short-term implantation as a diffusion membrane in biocompatible systems.

Cellulose

High aspect ratio cellulose nanocrystals (CNCs) extracted from tunicate were used to create so-ca... more High aspect ratio cellulose nanocrystals (CNCs) extracted from tunicate were used to create so-called cryogels from an ice-templating directional freeze-drying process. The structure of the resulting solid foam was investigated at the micro- and nanoscales by scanning electron microscopy and nitrogen adsorption measurements were used to extract the specific surface area. The mechanical properties were probed by compression tests. To highlight the specificities of tunicate CNC-based cryogels, results were compared with the one obtained from two other types of nanocellulose, namely cellulose nanofibrils (CNFs) from wood and CNCs from cotton, which exhibit different dimensions, aspect ratio, flexibility and crystallinity. While CNF- and cotton CNC-based cryogels exhibited a classical morphology characterized by a sheet-like structure, a particular honeycomb organization with individual particles was obtained in the case of tunicate CNC cryogels. The latter cryogels presented a very high specific surface area of about 122 m 2 g −1 , which is unexpected for foams prepared from a water-based process and much higher than what was obtained for CNF and cotton CNC cryogels (25 and 4 m 2 g −1 , respectively). High mechanical resistance and stiffness were also obtained with such tunicate CNC cryogels. These results are explained by the high crystallinity, aspect ratio and rigidity of the tunicate CNCs combined with the particular honeycomb architecture of the cryogel.

Chemical Science

Hydrogen production through direct sunlight-driven water splitting in Photo-Electrochemical Cells... more Hydrogen production through direct sunlight-driven water splitting in Photo-Electrochemical Cells (PECs) is a promising solution for energy sourcing. PECs need to respond to three criteria: sustainability, cost-effectiveness and stability. Here...

Small

Metallic conductive nanowires (NWs) with DNA bundle core are achieved, thanks to an original proc... more Metallic conductive nanowires (NWs) with DNA bundle core are achieved, thanks to an original process relying on double-stranded DNA alignment and physical vapor deposition (PVD) metallization steps involving a silicon substrate. First, bundles of DNA are suspended with a repeatable process between 2 µm high parallel electrodes with separating gaps ranging from 800 nm to 2 µm. The process consists in the drop deposition of a DNA lambda-phage solution on the electrodes followed by a naturally evaporation step. The deposition process is controlled by the DNA concentration within the buffer solution, the drop volume, and the electrode hydrophobicity. The suspended bundles are finally metallized with various thicknesses of titanium and gold by a PVD e-beam evaporation process. The achieved NWs have a width ranging from a few nanometers up to 100 nm. The electrical behavior of the achieved 60 and 80 nm width metallic NWs is shown to be Ohmic and their intrinsic resistance is estimated according to different geometrical models of the NW section area. For the 80 nm width NWs, a resistance of about few ohms is established, opening exploration fields for applications in microelectronics.

The Analyst, Jan 24, 2016

DNA is under continuous assault by environmental and endogenous reactive oxygen and alkylating sp... more DNA is under continuous assault by environmental and endogenous reactive oxygen and alkylating species, inducing the formation of mutagenic, toxic and genome destabilizing nucleobase lesions. Due to the implications of such genetic alterations in cell death, aging, inflammation, neurodegenerative diseases and cancer, many efforts have been devoted to developing assays that aim at analyzing DNA repair activities from purified enzymes or cell extracts. The present work deals with the conception and application of a new, miniaturized and parallelized on surface-DNA biosensor to measure base excision repair (BER) activities. Such a bio-analytical tool was built by using the "click chemistry" approach to immobilize, on a glass slide, fluorescent stem-loop DNA probes, which contain a specific nucleobase lesion. The performance of this new high-throughput DNA repair analysis technology was determined by detecting uracil N-glycosylase and AP-endonuclease activities from purified e...

A novel concept for protein recognition has been developed. The recognition unit is a hybrid mole... more A novel concept for protein recognition has been developed. The recognition unit is a hybrid molecule obtained by conjugation of a small organic molecule to a synthetic polypeptide selected from a 16-membered set of 42 amino acid residue sequences. The sequences are unordered and have no prior relation to the target proteins. The concept is based on the hypothesis that a small set of sequences capable of hydrophobic interactions, hydrogen bonding and electrostatic interactions can yield a binder for any selected protein, provided that the small molecule shows medium affinity or better and is reasonably selective. The concept has been illustrated by the design, synthesis and evaluation of binders for three different proteins, the C-reactive protein, CRP, human Carbonic anhydrase II, HCAII, and Acetylcholine esterase, AChE. Highly efficient binders for CRP have been developed by conjugation of a derivative of the natural ligand, phosphocholine, to the side chain of one of the amino acids in each polypeptide. The binders in the set show a wide range of affinities for CRP and the tightest binder, 4-C10L17-PC6, binds almost irreversibly. Selected binders have been evaluated in human serum, where they capture CRP with high selectivity.High-affinity binders have been developed for HCAII, and the selectivity evaluated by extraction of the protein from blood. The binder 4-C37L34-B, a polypeptide conjugated to a spacered benzenesulphonamide residue, was able to extract Carbonic anhydrases specifically and to discriminate between the two isoforms of human Carbonic anhydrase. The conjugation of an acridine derivative to a polypeptide via a 14 atom spacer has been shown to yield a binder with high affinity and selectivity for AChE. The selectivity was demonstrated by extraction of AChE from Cerebrospinal fluid. This thesis focuses on the development of a fast and reliable procedure for the construction, selection and evaluation of protein binders, with the ambition to develop a technology that is applicable to the development of binders for all proteins.

Http Www Theses Fr, 2005

This report deals with a new process for preparing DNA microarrays using glass slides covered by ... more This report deals with a new process for preparing DNA microarrays using glass slides covered by a zirconium phosphonate monolayer deposited by Langmuir-Blodgett method. Oligonucleotides probes modified with a terminal phosphate were spotted onto the zirconated surface where they bound by formation of metal-oxygen covalent bonds. Performances of this new type of DNA microarrays were studied in biological conditions. An increase of the fluorescence intensity was observed when using a polyguanine spacer between the probe oligomer and the terminal phosphate. Then the synthesis of novel chiral P,N-ligands by desymmetrization of the achiral meso N,N'-dimethyl-1,2-diphenylethane-1,2-diamine backbone is described. This transformation was achieved by the selective introduction of a diphenylphosphine moiety on one of the two nitrogen centers. The coordination of this ligand (L) with Rh(I) and Pd(0) precursors led to the formation of complexes which can be of potential interest for catalysis.

Microfluidics and Nanofluidics, 2014