Generation of artificial vascular grafts as blood vessel substitutes is a primary challenge in bi... more Generation of artificial vascular grafts as blood vessel substitutes is a primary challenge in biomaterial and tissue-engineering research. Ideally, these grafts should be able to recapitulate physiological and mechanical properties of natural vessels and guide the assembly of an endothelial cell lining to ensure hemo-compatibility. In this paper, we advance on this challenging task by designing and fabricating 3D vessel analogues by two-photon laser lithography using a synthetic photoresist. These scaffolds guarantee human endothelial cell adhesion and proliferation, and proper elastic behavior to withstand the pressure exerted by blood flow.
ch15, which has been published in final form at 10.1002/9783527699773.ch15. This article may be u... more ch15, which has been published in final form at 10.1002/9783527699773.ch15. This article may be used for non-commercial purposes in accordance With Wiley Terms and Conditions for self-archiving.
Materials GOx immobilization Km app / mM Ref. PVA-g-P(4-VP) films Physical entrapment 19 1 Nafion... more Materials GOx immobilization Km app / mM Ref. PVA-g-P(4-VP) films Physical entrapment 19 1 Nafion film Covalent attachment with GA, BSA and Nafion 14.91 2 Chitosan matrix Covalent attachment with GA in a 5% (v/v) glycerol solution 14.2 3 NiO modified glassy carbon electrodes Co-deposition with NiO nanoparticles at 0.8 V for 15 min in buffer solution 2.7 4 Gold nanoparticles Thiol-Cystamine modification of Au with IO4oxidized GOx 4.3
Biomarkers detection at an ultra-low concentration in biofluids (blood, serum, saliva, etc.) is a... more Biomarkers detection at an ultra-low concentration in biofluids (blood, serum, saliva, etc.) is a key point for the early diagnosis success and the development of personalized therapies. However, it remains a challenge due to limiting factors like (i) the complexity of analyzed media, and (ii) the aspecificity detection and the poor sensitivity of the conventional methods. In addition, several applications require the integration of the primary sensors with other devices (microfluidic devices, capillaries, flasks, vials, etc.) where transducing the signal might be difficult, reducing performances and applicability. In the present work, we demonstrate a new class of optical biosensor we have developed integrating an optical waveguide (OWG) with specific plasmonic surfaces. Exploiting the plasmonic resonance, the devices give consistent results in surface enhanced Raman spectroscopy (SERS) for continuous and label-free detection of biological compounds. The OWG allows driving optical ...
Organic electrochemical transistors (OECTs) comprised of organic mixed conductors can operate in ... more Organic electrochemical transistors (OECTs) comprised of organic mixed conductors can operate in aqueous, biological media and translate low magnitude ionic fluctuations of biological origin into measurable electrical signals. The growing technological interest in these bio-transducers makes the fundamental understanding of ion-to-electron coupling extremely important for the design of new materials and devices. One crucial aspect in this process that has been so far disregarded is the water taken up by the film during device operation and its effects on device performance. Here, using a series of the same electrolyte with varying ion concentrations, we quantify the amount of water that is incorporated into a hydrophilic p-type organic semiconductor film alongside the dopant anions and investigate structural and morphological changes occurring in the film upon electrochemical doping. We show that infiltration of the hydrated dopant ions into the film irreversibly changes the polymer structure and negatively impacts the efficiency, reversibility and speed of charge generation. When less water is injected into the channel, OECTs exhibit higher transconductance and faster switching speeds. Although swelling is commonly suggested to be a necessity for efficient ion-to-electron transduction, this work uncovers the negative impact of a swollen channel material on the performance of accumulation mode OECTs and lays the foundation for future materials design.
Super-hydrophobic micro-patterned surfaces are ideal substrates for the controlled self-assembly ... more Super-hydrophobic micro-patterned surfaces are ideal substrates for the controlled self-assembly and substratefree characterization of biological molecules. In this device, the tailored surface supports a micro-volume drop containing the molecules of interest. While the quasi-spherical drop is evaporating under controlled conditions, its de-wetting direction is guided by the pillared microstructure on top of the device, leading to the formation of threads between the neighboring pillars. This effect has been exploited here to elucidate the mechanism triggering the formation of amyloid fibers and oligomers in tau related neurodegenerative diseases. By using Raman spectroscopy, we demonstrate that the fiber bridging the pillars contains β-sheets, a characteristic feature of amyloid aggregation. We propose that the combination of laminar flow, shear stress and molecular crowding taking place while the drop is evaporating on the SHMS, induces the reorganization of the tau protein secondary structure and we suggest that this effect could in fact closely mimic the actual mechanism occurring in the human brain environment. Such a straightforward technique opens up new possibilities in the field of self-assembly of biomolecules and their characterization by different methods (SEM, AFM, Raman spectroscopy, TEM), in a single device.
Background: Dental procedures often elicit pain and fear in pediatric dental patients. Aim: To ev... more Background: Dental procedures often elicit pain and fear in pediatric dental patients. Aim: To evaluate the feasibility and effectiveness of immersive virtual reality as an attention distraction analgesia technique for pain management in children and adolescents undergoing painful dental procedures. Design: Using a within-subjects design, five patients (mean age 13.20 years old, SD 2.39) participated. Patients received tethered immersive interactive virtual reality distraction in an Oculus Rift VR helmet (experimental condition) during one dental procedure (a single dental filling or tooth extraction). On a different visit to the same dentist (e.g., 1 week later), each patient also received a comparable dental procedure during the control condition "treatment as usual" (treatment order randomized). After each procedure, children self-rated their "worst pain," "pain unpleasantness," "time spent thinking about pain," "presence in VR," "fun," and "nausea" levels during the dental procedures, using graphic rating scales. Results: Patients reported significantly lower "worst pain" and "pain unpleasantness," and had significantly more fun during VR, compared to a comparable dental procedure with No VR. Using Oculus Rift VR goggles, patients reported a "strong sense of going inside the computer-generated world," without side effects. The dentist preferred having the patients in VR. Conclusion: Results of this pilot study provide preliminary evidence of the feasibility of using immersive, interactive VR to distract pediatric dental patients and increase fun of children during dental procedures.
In this paper, we propose the use of a standing nanowires array, constituted by plasmonic active ... more In this paper, we propose the use of a standing nanowires array, constituted by plasmonic active gold wires grown on iron disks, and partially immersed in a supporting alumina matrix, for surface-enhanced Raman spectroscopy applications. The galvanic process was used to fabricate nanowires in pores of anodized alumina template, making this device cost-effective. This fabrication method allows for the selection of size, diameter, and spatial arrangement of nanowires. The proposed device, thanks to a detailed design analysis, demonstrates a broadband plasmonic enhancement effect useful for many standard excitation wavelengths in the visible and NIR. The trigonal pores arrangement gives an efficiency weakly dependent on polarization. The devices, tested with 633 and 830 nm laser lines, show a significant Raman enhancement factor, up to around 6 × 10⁴, with respect to the flat gold surface, used as a reference for the measurements of the investigated molecules.
In this paper graphene over SiO 2 /Si substrate was used as a substrate to fabricate SERS device.... more In this paper graphene over SiO 2 /Si substrate was used as a substrate to fabricate SERS device. A thin film was deposited over graphene and annealed at 250°C. The substrate was examined after chemisorption of two molecules; rhodamine 6G which is a fluorescent dye, and 3-mercaptobenzoic acid, a thiol molecule. SERS enhancement factor for the proposed device is estimated to be 2.1 × 10 6 with respect to the flat silver substrate deposited over Si. The experimental results were compared in two ways; a) by using electromagnetic field calculation and b) quantum mechanical calculation derived from density function theory. The experimental findings were consistent with the theoretical observations.
Raman on suspended DNA: Novel super-hydrophobic approach for structural studies. Microelectronic ... more Raman on suspended DNA: Novel super-hydrophobic approach for structural studies. Microelectronic Engineering.
In bio-imaging by electron microscopy, damage of the sample and limited contrast are the two main... more In bio-imaging by electron microscopy, damage of the sample and limited contrast are the two main hurdles for reaching high image quality. We extend a new preparation method based on nanofabrication and super-hydrophobicity to the imaging and structural studies of nucleic acids, nucleic acid-protein complexes (DNA/Rad51 repair protein complex) and neuronal ion channels (gap-junction, K + and GABA A channels) as paradigms of biological significance and increasing complexity. The preparation method is based on the liquid phase and is compatible with physiological conditions. Only in the very last stage, samples are dried for TEM analysis. Conventional TEM and high-resolution TEM (HRTEM) were used to achieve a resolution of 3.3 and 1.5 Å, respectively. The EM dataset quality allows the determination of relevant structural and metrological information on the DNA structure, DNA-protein interactions and ion channels, allowing the identification of specific macromolecules and their structure. Results and discussion The present approach can be considered a unifying technique that can be applied to different biological systems where the † Electronic supplementary information (ESI) available. See
In order to develop surfaces with improved cell culture biocompatibility, we optimized a solvent-... more In order to develop surfaces with improved cell culture biocompatibility, we optimized a solvent-casting and particulate-leaching fabrication technique to create porous three-dimensional polycaprolactone scaffolds. These biocompatible porous surfaces were realized by means of NaCl particles as porogen; salt leaching by immersion in distilled water created porosity and pore interconnectivity in the material. Scanning electron microscopy and mercury intrusion porosimetry were used for the measurement of porosity, pore size distribution, permeability and compressibility. To evaluate scaffold biocompatibility, fibroblasts were cultured on the porous surfaces and confocal immunofluorescence characterization indicated that they were effective for in vitro cell culture and practical tissue engineering applications.
Users may download and print one copy of any publication from the public portal for the purpose... more Users may download and print one copy of any publication from the public portal for the purpose of private study or research. You may not further distribute the material or use it for any profit-making activity or commercial gain You may freely distribute the URL identifying the publication in the public portal If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.
We present a detailed investigation of the terahertz vibrational dynamics of 3-methylpentane perf... more We present a detailed investigation of the terahertz vibrational dynamics of 3-methylpentane performed by means of high resolution inelastic X-ray scattering (IXS). We probe the dynamics in a large temperature range, which includes the glass, the supercooled liquid and the liquid phases. The characteristic frequency of the excitations follows a well defined dispersion curve extending beyond 8 nm −1 at all the investigated temperatures, indicating the persistence of a solid-like behaviour also in the liquid phase. This implies the existence of a pseudo-Brillouin zone whose size compares surprisingly well with the periodicity inferred from the first sharp diffraction peak in the static structure factor. We show that, in the investigated temperature range, both sizes undergo a variation of about 15-20 %, comparable to that of the average intermolecular distance. We finally show that the IXS sound velocity coincides with the infinite frequency sound velocity previously inferred from visible and ultraviolet Brillouin spectroscopy data. This analysis confirms the role of the shear relaxation processes in determining the variation with frequency of the apparent sound velocity.
The DNA helix and its internal structures were directly imaged; characteristic lengths and inner ... more The DNA helix and its internal structures were directly imaged; characteristic lengths and inner components were measured and reported.
Scaffold design and fabrication are very important subjects for biomaterial, tissue engineering a... more Scaffold design and fabrication are very important subjects for biomaterial, tissue engineering and regenerative medicine research playing a unique role in tissue regeneration and repair. Among synthetic biomaterials Poly-ε-Caprolactone (PCL) is very attractive bioresorbable polyester due to its high permeability, biodegradability and capacity to be blended with other biopolymers. Thanks to its ability to naturally degrade in tissues, PCL has a great potential as a new material for implantable biomedical micro devices. This work focuses on the establishment of a micro fabrication process, by integrating lithography and micromolding fabrication techniques, for the realization of 3D microstructure PCL devices. Scaffold surface exhibits a combination in the patterned length scale; cylindrical pillars of 10 µm height and 10 µm diameter are arranged in a hexagonal lattice with periodicity of 30 µm and their sidewalls are nano-sculptured, with a regular pattern of grooves leading to a spatial modulation in the z direction. In order to demonstrate that these biocompatible pillared PCL substrates are suitable for a proper cell growth, NIH/3T3 mouse embryonic fibroblasts were seeded on them and cells key adhesion parameters were evaluated. Scanning Electron Microscopy and immunofluorescence analysis were carried out to check cell survival, proliferation and adhesion; cells growing on the PCL substrates appeared healthy and formed a well-developed network in close contact with the micro and nano features of the pillared surface. Those 3D scaffolds could be a promising solution for a wide range of applications within tissue engineering and regenerative medicine applications.
such as a protein, across a lipid bilayer. To create a membrane, two sub-microliter, lipid-encase... more such as a protein, across a lipid bilayer. To create a membrane, two sub-microliter, lipid-encased aqueous droplets are contacted-termed a droplet interface bilayer (DIB). The peptides adsorb to the protein cargo noncovalently and somehow ''carry'' the protein from one droplet to the other through the membrane. We then assay the translocated cargo through a fluorogenic assay. The DIB method recapitulates the findings of earlier studies involving Pep-1, including the dependence of protein transport on voltage and membrane charge, while also contributing new insights. Specifically, we found that the symmetry of the bilayer membrane may play a role in Pep-1mediated protein translocation. In addition, we used a newly developed peptide transduction domain mimic (PTDM) as a protein carrier, which exhibited distinct differences compared to Pep-1's mechanism. We've also used the DIB system to monitor the translocation of proteins through pores, such as the anthrax toxin. We anticipate that the DIB method may be useful for a variety of transport-based studies; in particular those which must make use of tiny quantities of purified species.
Generation of artificial vascular grafts as blood vessel substitutes is a primary challenge in bi... more Generation of artificial vascular grafts as blood vessel substitutes is a primary challenge in biomaterial and tissue-engineering research. Ideally, these grafts should be able to recapitulate physiological and mechanical properties of natural vessels and guide the assembly of an endothelial cell lining to ensure hemo-compatibility. In this paper, we advance on this challenging task by designing and fabricating 3D vessel analogues by two-photon laser lithography using a synthetic photoresist. These scaffolds guarantee human endothelial cell adhesion and proliferation, and proper elastic behavior to withstand the pressure exerted by blood flow.
ch15, which has been published in final form at 10.1002/9783527699773.ch15. This article may be u... more ch15, which has been published in final form at 10.1002/9783527699773.ch15. This article may be used for non-commercial purposes in accordance With Wiley Terms and Conditions for self-archiving.
Materials GOx immobilization Km app / mM Ref. PVA-g-P(4-VP) films Physical entrapment 19 1 Nafion... more Materials GOx immobilization Km app / mM Ref. PVA-g-P(4-VP) films Physical entrapment 19 1 Nafion film Covalent attachment with GA, BSA and Nafion 14.91 2 Chitosan matrix Covalent attachment with GA in a 5% (v/v) glycerol solution 14.2 3 NiO modified glassy carbon electrodes Co-deposition with NiO nanoparticles at 0.8 V for 15 min in buffer solution 2.7 4 Gold nanoparticles Thiol-Cystamine modification of Au with IO4oxidized GOx 4.3
Biomarkers detection at an ultra-low concentration in biofluids (blood, serum, saliva, etc.) is a... more Biomarkers detection at an ultra-low concentration in biofluids (blood, serum, saliva, etc.) is a key point for the early diagnosis success and the development of personalized therapies. However, it remains a challenge due to limiting factors like (i) the complexity of analyzed media, and (ii) the aspecificity detection and the poor sensitivity of the conventional methods. In addition, several applications require the integration of the primary sensors with other devices (microfluidic devices, capillaries, flasks, vials, etc.) where transducing the signal might be difficult, reducing performances and applicability. In the present work, we demonstrate a new class of optical biosensor we have developed integrating an optical waveguide (OWG) with specific plasmonic surfaces. Exploiting the plasmonic resonance, the devices give consistent results in surface enhanced Raman spectroscopy (SERS) for continuous and label-free detection of biological compounds. The OWG allows driving optical ...
Organic electrochemical transistors (OECTs) comprised of organic mixed conductors can operate in ... more Organic electrochemical transistors (OECTs) comprised of organic mixed conductors can operate in aqueous, biological media and translate low magnitude ionic fluctuations of biological origin into measurable electrical signals. The growing technological interest in these bio-transducers makes the fundamental understanding of ion-to-electron coupling extremely important for the design of new materials and devices. One crucial aspect in this process that has been so far disregarded is the water taken up by the film during device operation and its effects on device performance. Here, using a series of the same electrolyte with varying ion concentrations, we quantify the amount of water that is incorporated into a hydrophilic p-type organic semiconductor film alongside the dopant anions and investigate structural and morphological changes occurring in the film upon electrochemical doping. We show that infiltration of the hydrated dopant ions into the film irreversibly changes the polymer structure and negatively impacts the efficiency, reversibility and speed of charge generation. When less water is injected into the channel, OECTs exhibit higher transconductance and faster switching speeds. Although swelling is commonly suggested to be a necessity for efficient ion-to-electron transduction, this work uncovers the negative impact of a swollen channel material on the performance of accumulation mode OECTs and lays the foundation for future materials design.
Super-hydrophobic micro-patterned surfaces are ideal substrates for the controlled self-assembly ... more Super-hydrophobic micro-patterned surfaces are ideal substrates for the controlled self-assembly and substratefree characterization of biological molecules. In this device, the tailored surface supports a micro-volume drop containing the molecules of interest. While the quasi-spherical drop is evaporating under controlled conditions, its de-wetting direction is guided by the pillared microstructure on top of the device, leading to the formation of threads between the neighboring pillars. This effect has been exploited here to elucidate the mechanism triggering the formation of amyloid fibers and oligomers in tau related neurodegenerative diseases. By using Raman spectroscopy, we demonstrate that the fiber bridging the pillars contains β-sheets, a characteristic feature of amyloid aggregation. We propose that the combination of laminar flow, shear stress and molecular crowding taking place while the drop is evaporating on the SHMS, induces the reorganization of the tau protein secondary structure and we suggest that this effect could in fact closely mimic the actual mechanism occurring in the human brain environment. Such a straightforward technique opens up new possibilities in the field of self-assembly of biomolecules and their characterization by different methods (SEM, AFM, Raman spectroscopy, TEM), in a single device.
Background: Dental procedures often elicit pain and fear in pediatric dental patients. Aim: To ev... more Background: Dental procedures often elicit pain and fear in pediatric dental patients. Aim: To evaluate the feasibility and effectiveness of immersive virtual reality as an attention distraction analgesia technique for pain management in children and adolescents undergoing painful dental procedures. Design: Using a within-subjects design, five patients (mean age 13.20 years old, SD 2.39) participated. Patients received tethered immersive interactive virtual reality distraction in an Oculus Rift VR helmet (experimental condition) during one dental procedure (a single dental filling or tooth extraction). On a different visit to the same dentist (e.g., 1 week later), each patient also received a comparable dental procedure during the control condition "treatment as usual" (treatment order randomized). After each procedure, children self-rated their "worst pain," "pain unpleasantness," "time spent thinking about pain," "presence in VR," "fun," and "nausea" levels during the dental procedures, using graphic rating scales. Results: Patients reported significantly lower "worst pain" and "pain unpleasantness," and had significantly more fun during VR, compared to a comparable dental procedure with No VR. Using Oculus Rift VR goggles, patients reported a "strong sense of going inside the computer-generated world," without side effects. The dentist preferred having the patients in VR. Conclusion: Results of this pilot study provide preliminary evidence of the feasibility of using immersive, interactive VR to distract pediatric dental patients and increase fun of children during dental procedures.
In this paper, we propose the use of a standing nanowires array, constituted by plasmonic active ... more In this paper, we propose the use of a standing nanowires array, constituted by plasmonic active gold wires grown on iron disks, and partially immersed in a supporting alumina matrix, for surface-enhanced Raman spectroscopy applications. The galvanic process was used to fabricate nanowires in pores of anodized alumina template, making this device cost-effective. This fabrication method allows for the selection of size, diameter, and spatial arrangement of nanowires. The proposed device, thanks to a detailed design analysis, demonstrates a broadband plasmonic enhancement effect useful for many standard excitation wavelengths in the visible and NIR. The trigonal pores arrangement gives an efficiency weakly dependent on polarization. The devices, tested with 633 and 830 nm laser lines, show a significant Raman enhancement factor, up to around 6 × 10⁴, with respect to the flat gold surface, used as a reference for the measurements of the investigated molecules.
In this paper graphene over SiO 2 /Si substrate was used as a substrate to fabricate SERS device.... more In this paper graphene over SiO 2 /Si substrate was used as a substrate to fabricate SERS device. A thin film was deposited over graphene and annealed at 250°C. The substrate was examined after chemisorption of two molecules; rhodamine 6G which is a fluorescent dye, and 3-mercaptobenzoic acid, a thiol molecule. SERS enhancement factor for the proposed device is estimated to be 2.1 × 10 6 with respect to the flat silver substrate deposited over Si. The experimental results were compared in two ways; a) by using electromagnetic field calculation and b) quantum mechanical calculation derived from density function theory. The experimental findings were consistent with the theoretical observations.
Raman on suspended DNA: Novel super-hydrophobic approach for structural studies. Microelectronic ... more Raman on suspended DNA: Novel super-hydrophobic approach for structural studies. Microelectronic Engineering.
In bio-imaging by electron microscopy, damage of the sample and limited contrast are the two main... more In bio-imaging by electron microscopy, damage of the sample and limited contrast are the two main hurdles for reaching high image quality. We extend a new preparation method based on nanofabrication and super-hydrophobicity to the imaging and structural studies of nucleic acids, nucleic acid-protein complexes (DNA/Rad51 repair protein complex) and neuronal ion channels (gap-junction, K + and GABA A channels) as paradigms of biological significance and increasing complexity. The preparation method is based on the liquid phase and is compatible with physiological conditions. Only in the very last stage, samples are dried for TEM analysis. Conventional TEM and high-resolution TEM (HRTEM) were used to achieve a resolution of 3.3 and 1.5 Å, respectively. The EM dataset quality allows the determination of relevant structural and metrological information on the DNA structure, DNA-protein interactions and ion channels, allowing the identification of specific macromolecules and their structure. Results and discussion The present approach can be considered a unifying technique that can be applied to different biological systems where the † Electronic supplementary information (ESI) available. See
In order to develop surfaces with improved cell culture biocompatibility, we optimized a solvent-... more In order to develop surfaces with improved cell culture biocompatibility, we optimized a solvent-casting and particulate-leaching fabrication technique to create porous three-dimensional polycaprolactone scaffolds. These biocompatible porous surfaces were realized by means of NaCl particles as porogen; salt leaching by immersion in distilled water created porosity and pore interconnectivity in the material. Scanning electron microscopy and mercury intrusion porosimetry were used for the measurement of porosity, pore size distribution, permeability and compressibility. To evaluate scaffold biocompatibility, fibroblasts were cultured on the porous surfaces and confocal immunofluorescence characterization indicated that they were effective for in vitro cell culture and practical tissue engineering applications.
Users may download and print one copy of any publication from the public portal for the purpose... more Users may download and print one copy of any publication from the public portal for the purpose of private study or research. You may not further distribute the material or use it for any profit-making activity or commercial gain You may freely distribute the URL identifying the publication in the public portal If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.
We present a detailed investigation of the terahertz vibrational dynamics of 3-methylpentane perf... more We present a detailed investigation of the terahertz vibrational dynamics of 3-methylpentane performed by means of high resolution inelastic X-ray scattering (IXS). We probe the dynamics in a large temperature range, which includes the glass, the supercooled liquid and the liquid phases. The characteristic frequency of the excitations follows a well defined dispersion curve extending beyond 8 nm −1 at all the investigated temperatures, indicating the persistence of a solid-like behaviour also in the liquid phase. This implies the existence of a pseudo-Brillouin zone whose size compares surprisingly well with the periodicity inferred from the first sharp diffraction peak in the static structure factor. We show that, in the investigated temperature range, both sizes undergo a variation of about 15-20 %, comparable to that of the average intermolecular distance. We finally show that the IXS sound velocity coincides with the infinite frequency sound velocity previously inferred from visible and ultraviolet Brillouin spectroscopy data. This analysis confirms the role of the shear relaxation processes in determining the variation with frequency of the apparent sound velocity.
The DNA helix and its internal structures were directly imaged; characteristic lengths and inner ... more The DNA helix and its internal structures were directly imaged; characteristic lengths and inner components were measured and reported.
Scaffold design and fabrication are very important subjects for biomaterial, tissue engineering a... more Scaffold design and fabrication are very important subjects for biomaterial, tissue engineering and regenerative medicine research playing a unique role in tissue regeneration and repair. Among synthetic biomaterials Poly-ε-Caprolactone (PCL) is very attractive bioresorbable polyester due to its high permeability, biodegradability and capacity to be blended with other biopolymers. Thanks to its ability to naturally degrade in tissues, PCL has a great potential as a new material for implantable biomedical micro devices. This work focuses on the establishment of a micro fabrication process, by integrating lithography and micromolding fabrication techniques, for the realization of 3D microstructure PCL devices. Scaffold surface exhibits a combination in the patterned length scale; cylindrical pillars of 10 µm height and 10 µm diameter are arranged in a hexagonal lattice with periodicity of 30 µm and their sidewalls are nano-sculptured, with a regular pattern of grooves leading to a spatial modulation in the z direction. In order to demonstrate that these biocompatible pillared PCL substrates are suitable for a proper cell growth, NIH/3T3 mouse embryonic fibroblasts were seeded on them and cells key adhesion parameters were evaluated. Scanning Electron Microscopy and immunofluorescence analysis were carried out to check cell survival, proliferation and adhesion; cells growing on the PCL substrates appeared healthy and formed a well-developed network in close contact with the micro and nano features of the pillared surface. Those 3D scaffolds could be a promising solution for a wide range of applications within tissue engineering and regenerative medicine applications.
such as a protein, across a lipid bilayer. To create a membrane, two sub-microliter, lipid-encase... more such as a protein, across a lipid bilayer. To create a membrane, two sub-microliter, lipid-encased aqueous droplets are contacted-termed a droplet interface bilayer (DIB). The peptides adsorb to the protein cargo noncovalently and somehow ''carry'' the protein from one droplet to the other through the membrane. We then assay the translocated cargo through a fluorogenic assay. The DIB method recapitulates the findings of earlier studies involving Pep-1, including the dependence of protein transport on voltage and membrane charge, while also contributing new insights. Specifically, we found that the symmetry of the bilayer membrane may play a role in Pep-1mediated protein translocation. In addition, we used a newly developed peptide transduction domain mimic (PTDM) as a protein carrier, which exhibited distinct differences compared to Pep-1's mechanism. We've also used the DIB system to monitor the translocation of proteins through pores, such as the anthrax toxin. We anticipate that the DIB method may be useful for a variety of transport-based studies; in particular those which must make use of tiny quantities of purified species.
Uploads
Papers by Andrea Giugni