Ranco, Italy
Ranco, Italy

Time filter

Source Type

Giudicatti S.,University of Pavia | Valsesia A.,Plasmore S.r.l. | Marabelli F.,University of Pavia | Colpo P.,European Commission - Joint Research Center Ispra | Rossi F.,European Commission - Joint Research Center Ispra
Physica Status Solidi (A) Applications and Materials Science | Year: 2010

We investigate nanostructured surfaces consisting of a hexagonal lattice of polymeric pillars embedded in a gold matrix. These systems are prepared by a new fabrication technique based on plasma assisted deposition and colloidal lithography. A complete characterization of such surfaces is performed by angle resolved reflectance and transmittance measurements. Both delocalized and localized plasmonic modes can be identified: their reciprocal interplay allows to observe spectral features and to detect refractive index changes related to one of the sample interfaces by measurements performed with a light beam incident from the opposite side. This intriguing behaviour, together with ease of use and low cost of the deposition procedure, make this kind of nanostructures particularly interesting in biosensing applications. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Giudicatti S.,University of Pavia | Marabelli F.,University of Pavia | Valsesia A.,Plasmore S.r.l. | Pellacani P.,Plasmore S.r.l. | And 2 more authors.
Journal of the Optical Society of America B: Optical Physics | Year: 2012

Nanostructured surfaces have proven to be effective in controlling the electric field distribution and triggering a series of interesting physical effects. In particular, ordered metallic lattices with a typical size of the same order of magnitude of the wavelength of the incident radiation exhibit extraordinary transmission and reflection properties and represent a sensitive tool to exploit surface plasmon resonance for sensing applications. We investigated, either by experimental structural and optical measurements or by modeling and calculations, samples consisting of a two-dimensional array of polymeric pillars embedded in a gold film. In particular, we analyzed the dependence of the plasmonic resonance on the pillar size. We showed that a peculiar interplay among localized modes and propagating surface plasmon polaritons exists for some selected conditions and affects the spectral distribution, lifetime, and field configuration of the plasmonic excitations. © 2012 Optical Society of America.

Agency: European Commission | Branch: FP7 | Program: MC-IAPP | Phase: FP7-PEOPLE-2011-IAPP | Award Amount: 589.91K | Year: 2011

The objective of the IMPRESS project is to develop an affordable, portable, multiplexing and flexible Surface Plasmon Resonance (SPR) biosensor device (the IMPRESSOR), based on Plasmores nanotechnology expertise, to obtain a fast impression of the quality and safety of food. Affordable: the system will be affordable for any small or medium enterprise or even private user, which is producing or distributing or consuming food in any country or region of the world. Portable: the system will be easy-to-use in any environment and must work outside any specialized laboratory. Multiplexed: the system will be able to measure the concentration of many contaminants in a single sample of food and within a single measurement. Flexible: the system is designed to develop assays according to the wishes of the future users (customized). Fast: measurements are done in minutes and the sample-to-result time will be around 30 minutes. This will allow the real time monitoring of the quality of food. This system will be constituted by two fundamental elements: 1) A disposable biochip customized for the detection of a set of parameters of the quality of the food (e.g. the detection of a set of allergens, toxins or antibiotics) and 2) an electronic reading system enabling the dispensing and the analytical screening of the food sample and the electronic evaluation, storage and communication of the results. Such a system will have a huge impact in the food monitoring protocols and will significantly contribute to the spreading of alternative, fast and reliable analytical methods for food safety control. This will help: - industries and distributors to provide safer and healthier food products, - public regulatory bodies to improve the quality of the food control tests while reducing the assay costs, - end-users and small distributors to verify the quality of their everyday food products

Agency: European Commission | Branch: FP7 | Program: CP-FP | Phase: HEALTH.2011.1.1-1 | Award Amount: 6.38M | Year: 2012

Proteins are extremely malleable building blocks of life involved in all aspects of biology. Many diseases are caused by proteins aberrations, and proteins are frequent targets of intervention. Mapping all proteins and their functions are expected to yield pervasive medical and biotechnological benefits. However, even the most comprehensive and high-throughput proteins discovery technologies are seriously challenged by the extreme diversity and low abundance of many proteome components; a problem, compounded by the lack of affinity reagents and validated probes for sample preparation and identification. Our concept is that shorter protein fragments, or peptides, may offer solutions to many of these problems as peptides may represent or mimic proteins. Using in situ solid-phase peptide synthesis, computerized photolithography and novel photochemistry, we have recently generated peptide microarrays of up to 2 million addressable peptides. This unprecedented high-density and high-content peptide microarray technology could make inroads into the kind of high-throughput analysis needed to address the entire human proteome. Here, we aim to exploit this potential by using and improving three different, yet complementary, label-free detection technologies allowing sensitive, high-resolution determinations of the identity, quality and/or modification of individual members of a peptide microarray, and real-time monitoring of any interacting molecular receptor. We will also develop peptides as rapid, specific, and renewable affinity reagents for complex sample preparation, and develop peptides as probes and complex biosensors. Three SMEs constitute the backbone of this collaboration, receiving 50% of the budget, and enjoying significant opportunities from the booming protein/peptide microarray market. Furthermore, solutions to these unmet needs of proteomics are believed to have incalculable benefits for European health, innovativeness and competiveness.

Picciolini S.,Fondazione Don Carlo Gnocchi ONLUS | Picciolini S.,Plasmore S.r.l. | Mehn D.,Fondazione Don Carlo Gnocchi ONLUS | Morasso C.,Fondazione Don Carlo Gnocchi ONLUS | And 9 more authors.
ACS Nano | Year: 2014

In our study, 2D nanopillar arrays with plasmonic crystal properties are optimized for surface-enhanced Raman spectroscopy (SERS) application and tested in a biochemical assay for the simultaneous detection of multiple genetic leukemia biomarkers. The special fabrication process combining soft lithography and plasma deposition techniques allows tailoring of the structural and chemical parameters of the crystal surfaces. In this way, it has been possible to tune the plasmonic resonance spectral position close to the excitation wavelength of the monochromatic laser light source in order to maximize the enhancing properties of the substrate. Samples are characterized by scanning electron microscopy and reflectance measurements and tested for SERS activity using malachite green. Besides, as the developed substrate had been prepared on a simple glass slide, SERS detection from the support side is also demonstrated. The optimized substrate is functionalized with thiol-modified capture oligonucleotides, and concentration-dependent signal of the target nucleotide is detected in a sandwich assay with labeled gold nanoparticles. Gold nanoparticles functionalized with different DNA and various Raman reporters are applied in a microarray-based assay recognizing a disease biomarker (Wilms tumor gene) and housekeeping gene expressions in the same time on spatially separated microspots. The multiplexing performance of the SERS-based bioassay is illustrated by distinguishing Raman dyes based on their complex spectral fingerprints. © 2014 American Chemical Society.

Bottazzi B.,Humanitas Clinical and Research Center | Fornasari L.,University of Pavia | Frangolho A.,Plasmore S.r.l. | Giudicatti S.,University of Pavia | And 6 more authors.
Journal of Biomedical Optics | Year: 2014

This paper describes a new multiplexed label-free biosensor. The detection technology is based on nanostructured gold-polymer surfaces. These surfaces support surface plasmon resonance modes that can be probed by a miniaturized optical setup. The optical characterization of the sensing chip shows the sensitivity and the limit-of-detection to refractive index changes. Moreover, by studying the progressive adhesion of molecular monolayers of polyelectrolytes, the decay of the plasmonic mode electric field above the surface has been reconstructed. A multiplexed label-free biosensing device is then described and characterized in terms of sensitivity, lateral resolution, and sensitivity to a model biological assay. The sensitivity in imaging mode of the device is of the order of 10-6 refractive index units, while the measured lateral resolution is 6.25 μm within a field of view of several tenths of mm2, making the instrument unique in terms of multiplexing capability. Finally, the proof-of-concept application of the technology as a point-of-care diagnostic tool for an inflammatory marker is demonstrated. © 2014 Society of Photo-Optical Instrumentation Engineers.

Floris F.,University of Pavia | Figus C.,University of Cagliari | Fornasari L.,University of Pavia | Patrini M.,University of Pavia | And 10 more authors.
Journal of Physical Chemistry Letters | Year: 2014

Ultrathin films of silica realized by sol-gel synthesis and dip-coating techniques were successfully applied to predefined metal/polymer plasmonic nanostructures to spectrally tune their resonance modes and to increase their sensitivity to local refractive index changes. Plasmon resonance spectral shifts up to 100 nm with slope efficiencies of ∼8 nm/nm for increasing layer thickness were attained. In the ultrathin layer regime (<10 nm), which could be reached by suitable dilution of the silica precursors and optimization of the deposition speed, the sensitivity of the main plasmonic resonance to refractive index changes in aqueous solution could be increased by over 50% with respect to the bare plasmonic chip. Numerical simulations supported experimental data and unveiled the mechanism responsible for the optical sensitivity gain, proving an effective tool in the design of high-performance plasmonic sensors. SECTION: Plasmonics, Optical Materials, and Hard Matter © 2014 American Chemical Society.

Joshi S.,Wageningen University | Pellacani P.,Plasmore S.R.L | Van Beek T.A.,Wageningen University | Zuilhof H.,Wageningen University | Nielen M.W.F.,Wageningen University
Sensors and Actuators, B: Chemical | Year: 2014

Surface Plasmon Resonance (SPR) optical sensing is a label-free technique for real-time monitoring of biomolecular interactions. Recently, a portable imaging SPR (iSPR) prototype instrument, featuring a nanostructured gold chip, has been developed. In the present work, we investigated the crucial first steps, prior to eventual use of the nanostructured iSPR chip, i.e., its surface modification, in-depth surface characterization and the antifouling performance. Results were compared with conventional flat (i)SPR gold chips having the same surface chemistries, viz. different types of polyethylene glycol and zwitterionic polymers. Characterization of the (i)SPR chips before and after surface modification was performed using atomic force microscopy (AFM), scanning electron microscopy (SEM), water contact angle (WCA), X-ray photoelectron spectroscopy (XPS) and direct analysis in real time high resolution mass spectrometry (DART-HRMS). The antifouling properties were then studied using the nanostructured chip in the portable iSPR instrument and the flat gold chip in conventional SPR setup. The zwitterionic polymer surface chemistries showed the best antifouling properties. Comparison of the nanostructured iSPR chips with conventional flat (i)SPR gold chips showed that the latter perform slightly better in terms of surface modification as well as antifouling properties. The portable iSPR instrument is almost as sensitive as conventional iSPR (IBIS) and nine times less sensitive than conventional SPR (Biacore 3000). The nanostructured iSPR chip, along with the portable instrument, offers the advantage of about ten-fold reduction in instrument size, weight and costs compared to conventional (i)SPR instruments using flat gold, thus making it highly interesting for future biosensing applications. © 2014 Elsevier B.V. All rights reserved.

PubMed | University of Pavia, University of Cagliari and Plasmore S.r.l.
Type: | Journal: Beilstein journal of nanotechnology | Year: 2015

Biosensing technologies based on plasmonic nanostructures have recently attracted significant attention due to their small dimensions, low-cost and high sensitivity but are often limited in terms of affinity, selectivity and stability. Consequently, several methods have been employed to functionalize plasmonic surfaces used for detection in order to increase their stability. Herein, a plasmonic surface was modified through a controlled, silica platform, which enables the improvement of the plasmonic-based sensor functionality. The key processing parameters that allow for the fine-tuning of the silica layer thickness on the plasmonic structure were studied. Control of the silica coating thickness was achieved through a combined approach involving sol-gel and dip-coating techniques. The silica films were characterized using spectroscopic ellipsometry, contact angle measurements, atomic force microscopy and dispersive spectroscopy. The effect of the use of silica layers on the optical properties of the plasmonic structures was evaluated. The obtained results show that the silica coating enables surface protection of the plasmonic structures, preserving their stability for an extended time and inducing a suitable reduction of the regeneration time of the chip.

European Commission and Plasmore Srl | Date: 2012-05-31

A sensor device comprises a dielectric substrate (52); and a metal layer (53) on the substrate (52) with at least one array of cavities (54) therein and adapted to support L-SPR, each of the cavities (54) in the metal layer (53) having an opening (56) and a closed bottom (58) and widening from opening to bottom. A bed of dielectric material (62) is provided over the bottom (58) of each cavity (54) to reduce its apparent depth, the bed surface (62) being functionalized to bind to receptor moieties (64). This sensor device is particularly designed for SPR detection, but can be used in other detection techniques.

Loading Plasmore SRL collaborators
Loading Plasmore SRL collaborators