46 results on '"Tombelli S"'
Search Results
2. Optical Monitoring of Therapeutic Drugs with a Novel Fluorescence- Based POCT Device
- Author
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Berrettoni, C., Berneschi, S., Bernini, R., Giannetti, A., Grimaldi, I.A., Persichetti, G., Testa, G., Tombelli, S., Trono, C., and Baldini, F.
- Published
- 2014
- Full Text
- View/download PDF
3. Complex Nanostructures Based on Oligonucleotide Optical Switches and Nanoparticles for Intracellular mRNA Sensing and Silencing
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Adinolfi, B., Carpi, S., Giannetti, A., Nieri, P., Pellegrino, M., Sotgiu, G., Tombelli, S., Trono, C., Varchi, G., and Baldini, F.
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- 2014
- Full Text
- View/download PDF
4. Oligonucleotide optical switches for intracellular sensing
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Giannetti, A., Tombelli, S., and Baldini, F.
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- 2013
- Full Text
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5. Different approaches for the detection of thrombin by an electrochemical aptamer-based assay coupled to magnetic beads
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Centi, S., Messina, G., Tombelli, S., Palchetti, I., and Mascini, M.
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- 2008
- Full Text
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6. Development of an optical RNA-based aptasensor for C-reactive protein
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Bini, A., Centi, S., Tombelli, S., Minunni, M., and Mascini, M.
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- 2008
- Full Text
- View/download PDF
7. Analytical applications of aptamers
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Tombelli, S., Minunni, M., and Mascini, M.
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- 2005
- Full Text
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8. Development of biosensors with aptamers as bio-recognition element: the case of HIV-1 Tat protein
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Minunni, M., Tombelli, S., Gullotto, A., Luzi, E., and Mascini, M.
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- 2004
- Full Text
- View/download PDF
9. Real-time kinetic studies down to attomolar concentrations using a single-stage opto-biosensing platform
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Allsop, T, Mou, C, Neal, R, Mariani, Stefano, Nagel, D, Tombelli, S, Poole, A, Kalli, K, Hine, A, Webb, Dj, Culverhouse, P, Mascini, Marco, Minunni, Maria, and Bennion, I.
- Subjects
surface plasmon resonance, femptomolar - Published
- 2017
10. Real-time kinetic binding studies at attomolar concentrations in solution phase using a single-stage opto-biosensing platform based upon infrared surface plasmons
- Author
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Allsop, T., primary, Mou, C., additional, Neal, R., additional, Mariani, S., additional, Nagel, D., additional, Tombelli, S., additional, Poole, A., additional, Kalli, K., additional, Hine, A., additional, Webb, D. J., additional, Culverhouse, P., additional, Mascini, M., additional, Minunni, M., additional, and Bennion, I., additional
- Published
- 2017
- Full Text
- View/download PDF
11. A biosensor for the detection of highly repeated sequences in non-amplified genomic DNA
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Minunni, Maria, Mannelli, I., Spiriti, M. M., Tombelli, S., and Mascini, M.
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Highly repeated sequences ,QCM DNA sensing - Published
- 2004
12. An Electrochemical Immunoassay for HER2 Detection
- Author
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Al-Khafaji, Q A M, Harris, M, Tombelli, S, Laschi, S, Turner, Anthony, Mascini, M, Marrazza, G, Al-Khafaji, Q A M, Harris, M, Tombelli, S, Laschi, S, Turner, Anthony, Mascini, M, and Marrazza, G
- Abstract
In this paper, a simple and sensitive approach for human epidermal growth factor receptor 2 (HER2) detection is presented, using antibody-functionalised magnetic beads coupled to screen-printed cells. The immunoassay is based on a sandwich format in which a primary monoclonal antibody anti-HER2 is coupled to protein A modified magnetic beads. The modified beads are then used to capture the protein from the sample solution and a sandwich assay is performed by adding a secondary monoclonal antibody anti-HER2 labelled with biotin. The enzyme alkaline phosphatase (AP) conjugated with streptavidin and its substrate (1-naphthyl-phosphate) are then used for the electrochemical detection by differential pulse voltammetry (DPV). The experimental conditions for the immunoassay were optimised. The performance of the assay in terms of sensitivity, reproducibility and selectivity has been studied in buffer and serum samples from hospital patients.
- Published
- 2012
- Full Text
- View/download PDF
13. Affibodies as an alternative to antibodies inbiosensors for cancer markers
- Author
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Turner, Anthony, Harris, M., Tombelli, S., Marrazza, G., Turner, Anthony, Harris, M., Tombelli, S., and Marrazza, G.
- Published
- 2012
14. Improved procedures for immobilisation of oligonucleotides on gold-coated piezoelectric quartz crystals
- Author
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Tombelli, S, Mascini, M, Turner, APF, Tombelli, S, Mascini, M, and Turner, APF
- Abstract
The high sensitivity and specificity of DNA hybridisation techniques makes them powerful tools for environmental or clinical analysis. This work describes the development of a DNA piezoelectric biosensor for the detection of the hybridisation reaction. Attention was focused on the choice of the coating chemistry that could be used for the immobilisation of oligonucleotides onto the gold surface of the quartz crystal. Four immobilisation procedures were tested and compared considering the amount of immobilised probe, the extent of the hybridisation reaction, the possibility of regeneration and the absence of non-specific adsorption. All the experiments were performed with oligonucleotides of 25 bases (probe, target and non-complementary oligonucleotide). The four coating methods were all based on the use of self-assembled monolayers (SAM). Three of them employed the interaction between streptavidin and biotin for the immobilisation of a biotinylated probe. Results indicated that immobilisation of a biotinylated probe on streptavidin linked to a layer of carboxylated dextran provides higher sensitivity for the detection of the hybridisation reaction, absence of non-specific adsorption and a higher stability with respect to the regeneration step. (C) 2002 Elsevier Science B.V. All rights reserved.
- Published
- 2002
15. A DNA piezoelectric biosensor assay coupled with a polymerase chain reaction for bacterial toxicity determination in environmental samples
- Author
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Tombelli, S, Mascini, M, Sacco, C, Turner, APF, Tombelli, S, Mascini, M, Sacco, C, and Turner, APF
- Abstract
In this paper, we report the realisation of a DNA piezoelectric biosensor coupled with the polymerase chain reaction (PCR) for the detection of a specific bacterial toxicity factor. Biotinylated 23-mer probes were immobilised on the streptavidin coated gold surface of a quartz crystal; streptavidin was covalently bound to the thiol/dextran modified gold surface. The hybridisation of the immobilised probe with a synthetic oligonucleotide was investigated; the absence of non-specific adsorption was verified using a non-complementary oligonucleotide. Many cycles of measurements can be performed on the same crystal surface by regenerating the single strand with 1 mM HCl. The same hybridisation reaction was then performed using real samples of DNA extracted from bacteria and amplified by PCR. The PCR product was a fragment of a specific gene of Aeromonas hydrophila. The piezoelectric biosensor was able to distinguish samples containing the gene or not; in this way it was possible to determine the pathogenicity of different Aeromonas strains isolated from water, vegetables or human specimens. Experiments with non-specific samples confirmed the absence of adsorption or non-specific effects on the quartz crystal treated with the reported procedure. (C) 2000 Elsevier Science B.V. All rights reserved.
- Published
- 2000
16. Coupling of a DNA piezoelectric biosensor and polymerase chain reaction to detect apolipoprotein E polymorphisms
- Author
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Tombelli, S, Mascini, R, Braccini, L, Anichini, M, Turner, APF, Tombelli, S, Mascini, R, Braccini, L, Anichini, M, and Turner, APF
- Abstract
In this paper we report the coupling of the Polymerase Chain Reaction (PCR) with a piezoelectric biosensor to detect a point mutation in a human gene. Biotinylated 23-mer probes were immobilised on the streptavidin coated gold surface of a quartz crystal; streptavidin was covalently bound to the thiol/dextran modified gold surface. The hybridisation of the immobilised probes with a short sequence (23 mer) complementary, non-complementary and mismatched DNA was investigated: the device was able to distinguish the different synthetic oligonucleotides. Many cycles of measurements can be performed on the same crystal surface regenerating the single strand of DNA with 1 mM of HCl. The same hybridisation reaction was then performed using real samples of human DNA extracted from blood and amplified by PCR, following a standard procedure for genetic detection of the polymorphism of the apolipoprotein E (apoE) gene. The procedure was able to distinguish the sequences present in the different samples, which differ only in one base: in this way it was possible distinguish between different groups of genotypes with apoE typing. Experiments with blank samples confirmed the absence of adsorption or non-specific effects on the quartz crystal treated with the reported procedure. (C) 2000 Elsevier Science S.A. All rights reserved.
- Published
- 2000
17. Development of an optical RNA-based aptasensor for C-reactive protein
- Author
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Bini, A., primary, Centi, S., additional, Tombelli, S., additional, Minunni, M., additional, and Mascini, M., additional
- Published
- 2007
- Full Text
- View/download PDF
18. Improved procedures for immobilisation of oligonucleotides on gold-coated piezoelectric quartz crystals
- Author
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Tombelli, S, primary, Mascini, M, additional, and Turner, A.P.F, additional
- Published
- 2002
- Full Text
- View/download PDF
19. Biosensing with optical fiber gratings
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Chiavaioli Francesco, Baldini Francesco, Tombelli Sara, Trono Cosimo, and Giannetti Ambra
- Subjects
long-period grating ,tilted fiber bragg grating ,etched fiber bragg grating ,nanocoating ,nanostructure ,Physics ,QC1-999 - Abstract
Optical fiber gratings (OFGs), especially long-period gratings (LPGs) and etched or tilted fiber Bragg gratings (FBGs), are playing an increasing role in the chemical and biochemical sensing based on the measurement of a surface refractive index (RI) change through a label-free configuration. In these devices, the electric field evanescent wave at the fiber/surrounding medium interface changes its optical properties (i.e. intensity and wavelength) as a result of the RI variation due to the interaction between a biological recognition layer deposited over the fiber and the analyte under investigation. The use of OFG-based technology platforms takes the advantages of optical fiber peculiarities, which are hardly offered by the other sensing systems, such as compactness, lightness, high compatibility with optoelectronic devices (both sources and detectors), and multiplexing and remote measurement capability as the signal is spectrally modulated. During the last decade, the growing request in practical applications pushed the technology behind the OFG-based sensors over its limits by means of the deposition of thin film overlays, nanocoatings, and nanostructures, in general. Here, we review efforts toward utilizing these nanomaterials as coatings for high-performance and low-detection limit devices. Moreover, we review the recent development in OFG-based biosensing and identify some of the key challenges for practical applications. While high-performance metrics are starting to be achieved experimentally, there are still open questions pertaining to an effective and reliable detection of small molecules, possibly up to single molecule, sensing in vivo and multi-target detection using OFG-based technology platforms.
- Published
- 2017
- Full Text
- View/download PDF
20. Coupling of a DNA piezoelectric biosensor and polymerase chain reaction to detect apolipoprotein E polymorphisms
- Author
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Tombelli, S., Mascini, M., Braccini, L., Anichini, M., and Turner, A. P.
- Published
- 2000
- Full Text
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21. A Hetero-Bifunctional Spacer for the Smart Engineering of Carbon-Based Nanostructures
- Author
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Tuci G., Luconi L., Rossin A., Baldini F., Cicchi S., Tombelli S., Trono C., Giannetti A., Manet I., Fedeli S., Brandi A., Giambastiani G., Tuci G., Luconi L., Rossin A., Baldini F., Cicchi S., Tombelli S., Trono C., Giannetti A., Manet I., Fedeli S., Brandi A., and Giambastiani G.
- Abstract
© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. The cover picture shows a multifunctional platform based on carbon nanotubes, where a modular organic spacer acts as the anchoring site for controlled covalent functionalization of the surface. The combination of fluorescent dyes and post-derivatizable disulfide pendant arms capable of reacting with thiol end-capped (bio)molecules, generates optically traceable (bio)conjugates. The release of a pyridinic dye allows for a precise estimation of the functionalization loading through simple UV/Vis measurements. Details are given in the Full Paper by Giuliano Giambastiani etal. (DOI: 10.1002/cplu.201402391).
22. A Hetero-Bifunctional Spacer for the Smart Engineering of Carbon-Based Nanostructures
- Author
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Tuci G., Luconi L., Rossin A., Baldini F., Cicchi S., Tombelli S., Trono C., Giannetti A., Manet I., Fedeli S., Brandi A., Giambastiani G., Tuci G., Luconi L., Rossin A., Baldini F., Cicchi S., Tombelli S., Trono C., Giannetti A., Manet I., Fedeli S., Brandi A., and Giambastiani G.
- Abstract
© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. The cover picture shows a multifunctional platform based on carbon nanotubes, where a modular organic spacer acts as the anchoring site for controlled covalent functionalization of the surface. The combination of fluorescent dyes and post-derivatizable disulfide pendant arms capable of reacting with thiol end-capped (bio)molecules, generates optically traceable (bio)conjugates. The release of a pyridinic dye allows for a precise estimation of the functionalization loading through simple UV/Vis measurements. Details are given in the Full Paper by Giuliano Giambastiani etal. (DOI: 10.1002/cplu.201402391).
23. A Hetero-Bifunctional Spacer for the Smart Engineering of Carbon-Based Nanostructures
- Author
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Tuci G., Luconi L., Rossin A., Baldini F., Cicchi S., Tombelli S., Trono C., Giannetti A., Manet I., Fedeli S., Brandi A., Giambastiani G., Tuci G., Luconi L., Rossin A., Baldini F., Cicchi S., Tombelli S., Trono C., Giannetti A., Manet I., Fedeli S., Brandi A., and Giambastiani G.
- Abstract
© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Efforts have been made in recent years to develop novel functionalisation protocols aimed at imparting multimodality and improved properties to complex carbon-based nanostructures. The incorporation of cleavable bonds to the nanomaterial surface for the controlled release (or exchange) of specific molecules under appropriate chemical and biological settings is relatively unexplored. The design and synthesis of a hetero-bifunctional linker joining a "cleavable" disulfide moiety for the covalent anchoring of a wide range of thiol end-capped (bio)molecules and a "clickable" terminal acetylene group is described. The strategy is based on the well-established copper-mediated acetylene-azide coupling reaction between the acetylene linker and single-walled carbon nanotubes decorated with phenylazido pendant arms. As a result, easily "post-derivatisable" and traceable nanostructured platforms containing a linking group potentially available for a wide range of biological probes are prepared and completely characterised. Building on solid foundations: A hetero-bifunctional linker joining a "cleavable" disulfide moiety and a "clickable" terminal acetylene group was synthesized and used to decorate carbon nanotubes (CNTs). When used in combination with other selected terminal acetylene molecules, the linker can impart multimodality through a controlled click reaction to give carbon nanohybrids (see figure).
24. A Hetero-Bifunctional Spacer for the Smart Engineering of Carbon-Based Nanostructures
- Author
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Tuci G., Luconi L., Rossin A., Baldini F., Cicchi S., Tombelli S., Trono C., Giannetti A., Manet I., Fedeli S., Brandi A., Giambastiani G., Tuci G., Luconi L., Rossin A., Baldini F., Cicchi S., Tombelli S., Trono C., Giannetti A., Manet I., Fedeli S., Brandi A., and Giambastiani G.
- Abstract
© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. The cover picture shows a multifunctional platform based on carbon nanotubes, where a modular organic spacer acts as the anchoring site for controlled covalent functionalization of the surface. The combination of fluorescent dyes and post-derivatizable disulfide pendant arms capable of reacting with thiol end-capped (bio)molecules, generates optically traceable (bio)conjugates. The release of a pyridinic dye allows for a precise estimation of the functionalization loading through simple UV/Vis measurements. Details are given in the Full Paper by Giuliano Giambastiani etal. (DOI: 10.1002/cplu.201402391).
25. A Hetero-Bifunctional Spacer for the Smart Engineering of Carbon-Based Nanostructures
- Author
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Tuci G., Luconi L., Rossin A., Baldini F., Cicchi S., Tombelli S., Trono C., Giannetti A., Manet I., Fedeli S., Brandi A., Giambastiani G., Tuci G., Luconi L., Rossin A., Baldini F., Cicchi S., Tombelli S., Trono C., Giannetti A., Manet I., Fedeli S., Brandi A., and Giambastiani G.
- Abstract
© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Efforts have been made in recent years to develop novel functionalisation protocols aimed at imparting multimodality and improved properties to complex carbon-based nanostructures. The incorporation of cleavable bonds to the nanomaterial surface for the controlled release (or exchange) of specific molecules under appropriate chemical and biological settings is relatively unexplored. The design and synthesis of a hetero-bifunctional linker joining a "cleavable" disulfide moiety for the covalent anchoring of a wide range of thiol end-capped (bio)molecules and a "clickable" terminal acetylene group is described. The strategy is based on the well-established copper-mediated acetylene-azide coupling reaction between the acetylene linker and single-walled carbon nanotubes decorated with phenylazido pendant arms. As a result, easily "post-derivatisable" and traceable nanostructured platforms containing a linking group potentially available for a wide range of biological probes are prepared and completely characterised. Building on solid foundations: A hetero-bifunctional linker joining a "cleavable" disulfide moiety and a "clickable" terminal acetylene group was synthesized and used to decorate carbon nanotubes (CNTs). When used in combination with other selected terminal acetylene molecules, the linker can impart multimodality through a controlled click reaction to give carbon nanohybrids (see figure).
26. In-parallel polar monitoring of chemiluminescence emission anisotropy at the solid-liquid interface by an optical fiber radial array
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Aldo Roda, Francesco Baldini, Ambra Giannetti, Mara Mirasoli, Simone Berneschi, Sara Tombelli, Massimo Guardigli, Cosimo Trono, Martina Zangheri, Elisa Marchegiani, Berneschi S., Trono C., Mirasoli M., Giannetti A., Zangheri M., Guardigli M., Tombelli S., Marchegiani E., Baldini F., and Roda A.
- Subjects
Photon ,Materials science ,Optical fiber ,Chemiluminescence ,CCD camera detector ,02 engineering and technology ,01 natural sciences ,Analytical Chemistry ,law.invention ,lcsh:Biochemistry ,law ,Emission anisotropy ,lcsh:QD415-436 ,Physical and Theoretical Chemistry ,Diffusion (business) ,Anisotropy ,business.industry ,Multimode optical fiber ,010401 analytical chemistry ,Isotropy ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Dipole ,Optoelectronics ,0210 nano-technology ,business ,Biosensor ,Refractive index - Abstract
Chemiluminescence (CL) detection is widely employed in biosensors and miniaturized analytical devices since it offers high detectability and flexible device design (there are no geometry requirements for the measurement cell, except the ability to collect the largest fraction of emitted photons). Although the emission anisotropy phenomenon for an emitting dipole bound to the interface between two media with different refractive index is well known for fluorescence, it is still poorly investigated for CL reactions, in which the excited-state reaction products can diffuse in solution before the photon emission event. In this paper, we propose a simple method for the real-time evaluation of the CL emission anisotropy based on a radial array of optical fibers, embedded in a poly(methyl methacrylate) semicylinder and coupled with a Charge-Coupled Device (CCD) camera through a suitable interface. The polar-time evolutions of the CL emission have been studied for catalyzing enzymes immobilized onto a solid surface (heterogeneous configuration) or free in solution (homogeneous configuration). Evidence of the anisotropy phenomenon is observed, indicating that the lifetime of the excited-state products of the enzyme-catalyzed reactions is shorter than the time required for their diffusion in solution at a distance at which the CL can be considered isotropic. These results open new perspectives in the development of CL-based miniaturized analytical devices.
- Published
- 2020
27. A complete optical sensor system based on a POF-SPR platform and a thermo-stabilized flow cell for biochemical applications
- Author
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Sara Tombelli, Luigi Zeni, Francesco Chiavaioli, Ambra Giannetti, Cosimo Trono, Nunzio Cennamo, Francesco Baldini, Cennamo, N., Chiavaioli, F., Trono, C., Tombelli, S., Giannetti, A., Baldini, F., and Zeni, Luigi
- Subjects
Materials science ,Sensors system ,Flow cell ,Nanotechnology ,02 engineering and technology ,lcsh:Chemical technology ,01 natural sciences ,Biochemistry ,Article ,Analytical Chemistry ,Whole systems ,Robustness (computer science) ,Surface plasmon resonance ,Monolayer ,lcsh:TP1-1185 ,Electrical and Electronic Engineering ,Plastic optical fiber ,Instrumentation ,Sensor system ,010401 analytical chemistry ,021001 nanoscience & nanotechnology ,Atomic and Molecular Physics, and Optics ,0104 chemical sciences ,Biosensors ,flow cell ,surface plasmon resonance ,plastic optical fiber ,sensors system ,biosensors ,0210 nano-technology ,Biosensor - Abstract
An optical sensor platform based on surface plasmon resonance (SPR) in a plastic optical fiber (POF) integrated into a thermo-stabilized flow cell for biochemical sensing applications is proposed. This device has been realized and experimentally tested by using a classic receptor-analyte assay. For this purpose, the gold surface of the POF was chemically modified through the formation of a self-assembling monolayer. The surface robustness of the POF-SPR platform has been tested for the first time thanks to the flow cell. The experimental results show that the proposed device can be successfully used for label-free biochemical sensing. The final goal of this work is to achieve a complete, small-size, simple to use and low cost optical sensor system. The whole system with the flow cell and the optical sensor are extensively described, together with the experimental results obtained with an immunoglobulin G (IgG)/anti-IgG assay.
- Published
- 2016
28. Extended-sleeve resection for endoluminal recurrence of B3 thymoma: does aerogenous spread really exist?
- Author
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Tombelli S, Bongiolatti S, Pasini V, and Voltolini L
- Abstract
Thymomas are a variant of thymic epithelial tumours. They are considered malignant due to their tendency to local invasion and they showed lower metastatic behaviour. Distal metastasis is rare and an endobronchial mass is a rare presentation. First-line treatment for early-stage thymomas is surgery; for Masaoka-Koga stage III, neoadjuvant or adjuvant chemoradiation therapy should be considered in association with surgery after Multidisciplinary Tumour Board evaluation. We report a rare case of radical resection with type A extended-sleeve lobectomy in a 63-year-old woman who was affected by endobronchial recurrence of B3 thymoma, 31 months after complete and radical thymectomy., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery.)
- Published
- 2024
- Full Text
- View/download PDF
29. Case report: Complex left-carina resection: three-year single-center experience.
- Author
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Tombelli S, Viggiano D, Salimbene O, Trigiani M, Voltolini L, and Gonfiotti A
- Abstract
Carinal and tracheobronchial angle tumors have long been a contraindication for surgical removal; the technique of tracheal sleeve pneumonectomy makes it possible to approach this malignancy but still represents a surgical challenge. Left sleeve pneumonectomy is less common compared with right sleeve pneumonectomy and represents a minority component in the literature's case series due to the complexity of the anatomy. In addition, there is no standard for treatment strategy, and it must be assessed on a case-by-case basis. From 2020 to 2023, we performed three left tracheal sleeve pneumonectomies and one neocarina reconstruction surgery for benign lesions without lung resections. All cases were performed without cardiovascular support such as cardiopulmonary bypass and via median sternotomy. With a median length of stay of 21.5 days (between 14 days and 40 days), all patients were transferred to a physiotherapeutic rehabilitation facility for functional reactivation, where they received physiotherapeutic respiratory therapy given the slow functional recovery. The recorded 30-day mortality was 0. There is no standardized approach for left-sided sleeve pneumonectomy, and it is still a surgical challenge due to intraoperative and postoperative difficulties., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Tombelli, Viggiano, Salimbene, Trigiani, Voltolini and Gonfiotti.)
- Published
- 2024
- Full Text
- View/download PDF
30. Presentation and treatment of two massive intrapericardial lipoma. Case report.
- Author
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Tombelli S, Viggiano D, Salvicchi A, Bongiolatti S, Gonfiotti A, and Voltolini L
- Abstract
Introduction and Importance: Primary pericardial tumors are very rare with an overall incidence of 0.001-0.007 % and account for approximately 10 % of heart neoplasms. We present two clinical cases of massive mature intrapericardial lipomas (maximum size 270 × 230 mm) that were successfully treated in our department., Case Presentation: The first case is that of a 67-year-old male patient who underwent diagnostic investigations after the onset of dyspnea, which confirmed an intrapericardial mass of 270 × 230 mm in size that extended into the left lung field and was treated surgically by a clamshell incision. The second case is that of a 48-year-old patient who was completely asymptomatic and occasionally confirmed to have a 170 × 110 mm intrapericardial mass around the heart, which was surgically removed via sternotomy, also resulting in a mature lipoma., Clinical Discussion: In asymptomatic patients with small lesions, close monitoring is generally indicated. In asymptomatic patients with large lesions the decision should be made after multidisciplinary (MDT) evaluation. In symptomatic patients, surgical treatment is indicated. Lipomas are usually mature lesions with a capsule connected to the origin structure by one or more pedicles. Once reached the cardiac level and opened the pericardium, attention must be paid in resecting these pedicles given the area of origin and the possibility that they may be associated with vital structures., Conclusion: Both cases were characterized by slow recovery of normal cardiac function in the postoperative course. The average length of patient stay was 12 days, and one case was noted for readmission because a slight increase in pericardial effusion was detected at the scheduled ultrasound check after discharge. After further expert evaluation and steriodine therapy, the patient was discharged to a healthy home after 5 days. This report aims to describe the decision-making process, successful surgical treatment and outcomes of two rare massive intrapericardial tumors., Competing Interests: Conflict of interest statement The author declares that he has no relevant or material financial interests that relate to the research described in this paper. No conflicts of interest were shown., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2023
- Full Text
- View/download PDF
31. Biosensing by Polymer-Coated Etched Long-Period Fiber Gratings Working near Mode Transition and Turn-around Point.
- Author
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Dey TK, Trono C, Biswas P, Giannetti A, Basumallick N, Baldini F, Bandyopadhyay S, and Tombelli S
- Subjects
- Humans, Limit of Detection, Immunoassay, Biosensing Techniques methods
- Abstract
A methodology to enhance the sensitivity of long-period fiber gratings (LPFGs) based on the combination of three different enhancement approaches is presented; the methods here adopted are the working near mode transition (MT) of a cladding mode (CM), working near the turn-around point of a CM and the enhancement of the evanescent field of CMs by reducing the cladding diameter or by increasing the order number of CMs. In order to combine these enhancement methodologies, an electrostatic self-assembly (ESA) process was used to deposit a polymeric overlay, with a chosen thickness, onto the etched fiber. The add-layer sensitivity of the sensor was theoretically calculated, and the demonstration of the real applicability of the developed LPFG as a biosensor was performed by means of an IgG/anti-IgG immunoassay in human serum in a thermostated microfluidic system. The limits of detection (LODs) calculated by following different procedures (three times the standard deviation of the blank and the mean value of the residuals) were 6.9 × 10
-8 µg/mL and 4.5 × 10-6 µg/mL, respectively. The calculated LODs demonstrate the effectiveness of the applied methodology for sensitivity enhancement.- Published
- 2023
- Full Text
- View/download PDF
32. Lung Segmentectomy in NSCLC Surgery.
- Author
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Salvicchi A, Tombelli S, Mugnaini G, and Gonfiotti A
- Abstract
Current guidelines recommend surgery for early-stage non-small cell lung cancer (NSCLC). The standard treatment for patients with cT1N0 NSCLC has been lobectomy with lymph-node dissection, with sublobar resection used only in patients with inadequate cardio-respiratory reserve, with poor performance status, or who are elderly. In 1995, the Lung Cancer Study Group published the results of a randomized, prospective trial demonstrating the superiority of lobectomy compared with sublobar resection. From then on, wedge resection and segmentectomy were reserved exclusively for patients with poor functional reserve who could not tolerate lobectomy. Therefore, the exact role of segmentectomy has been controversial over the past 20 years. Recently, the randomized controlled trial JCOG0802/WJOG4607L demonstrated that segmentectomy was superior to lobectomy in patients with stage IA NSCLC (<2 cm and CTR < 0.5) in terms of both overall-survival and post-operative lung function. Based on these results, segmentectomy should be considered the standard surgical procedure for this patient group. In 2023, the randomized phase III CALGB 140503 (Alliance) trial demonstrated the efficacy and non-inferiority of sublobar resection, including wedge resection, for clinical stage IA NSCLC with tumor diameter of < 2 cm. This article is a narrative review of the current role of segmentectomy in lung cancer treatment and summarizes the most relevant studies in this context.
- Published
- 2023
- Full Text
- View/download PDF
33. Video-assisted transcervical-transtracheal repair of posterior wall laceration of thoracic trachea: A new approach. Case Report.
- Author
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Tombelli S, Viggiano D, Gatteschi L, Voltolini L, and Gonfiotti A
- Abstract
Iatrogenic tracheal lacerations are a rare but potentially fatal event. In selected acute cases, surgery plays a key role. Treatment can be conservative, for lacerations of less than 3 cm; surgical or endoscopic, depending on the size and location of the lesion and fan efficiency. There is no clear indication of the use of any of these approaches and the decision is therefore linked to local expertise. We present an emblematic clinical case of a 79 years old female patient undergoing polytrauma as a result of a road accident, without neurological damage, which required intubation and subsequent tracheotomy due to a significant limitation to ventilation. Imaging has shown the tracheal laceration involving the anterior wall and the pars membranacea up to the origin of the right main bronchus.A percutaneous tracheotomy was permormed without any improvement of the respiratory dynamic. Therefore, the patient underwent a surgical repair of the tracheal laceration with a hybrid mini-cervicotomic/endoscopic approach. This less invasive approach successfully repaired the extensive loss of substance., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Tombelli, Viggiano, Gatteschi, Voltolini and Gonfiotti.)
- Published
- 2023
- Full Text
- View/download PDF
34. Sensitivity Analysis of Sidelobes of the Lowest Order Cladding Mode of Long Period Fiber Gratings at Turn Around Point.
- Author
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Dey TK, Tombelli S, Roy A, Biswas P, Giannetti A, Basumallick N, Baldini F, Bandyopadhyay S, and Trono C
- Abstract
A new methodology to enhance the sensitivity of a long period fiber grating sensor (LPFG) at the Turn Around Point (TAP) is here presented. The LPFG sensor has been fabricated by etching the fiber up to 20.4 µm, until the sidelobes of dispersed LP
0,2 cladding mode appeared near TAP in aqueous medium. The dual peak sensitivity of the sidelobes was found to be 16,044 nm/SRIU (surrounding refractive index units) in the RI range from 1.333 to 1.3335.- Published
- 2022
- Full Text
- View/download PDF
35. An integrated device for fast and sensitive immunosuppressant detection.
- Author
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Tombelli S, Trono C, Berneschi S, Berrettoni C, Giannetti A, Bernini R, Persichetti G, Testa G, Orellana G, Salis F, Weber S, Luppa PB, Porro G, Quarto G, Schubert M, Berner M, Freitas PP, Cardoso S, Franco F, Silverio V, Lopez-Martinez M, Hilbig U, Freudenberger K, Gauglitz G, Becker H, Gärtner C, O'Connell MT, and Baldini F
- Subjects
- Humans, Immunoassay, Microfluidics, Silicon, Immunosuppressive Agents, Optical Devices
- Abstract
The present paper describes a compact point of care (POC) optical device for therapeutic drug monitoring (TDM). The core of the device is a disposable plastic chip where an immunoassay for the determination of immunosuppressants takes place. The chip is designed in order to have ten parallel microchannels allowing the simultaneous detection of more than one analyte with replicate measurements. The device is equipped with a microfluidic system, which provides sample mixing with the necessary chemicals and pumping samples, reagents and buffers into the measurement chip, and with integrated thin film amorphous silicon photodiodes for the fluorescence detection. Submicrometric fluorescent magnetic particles are used as support in the immunoassay in order to improve the efficiency of the assay. In particular, the magnetic feature is used to concentrate the antibody onto the sensing layer leading to a much faster implementation of the assay, while the fluorescent feature is used to increase the optical signal leading to a larger optical dynamic change and consequently a better sensitivity and a lower limit of detection. The design and development of the whole integrated optical device are here illustrated. In addition, detection of mycophenolic acid and cyclosporine A in spiked solutions and in microdialysate samples from patient blood with the implemented device are reported., (© 2021. The Author(s).)
- Published
- 2022
- Full Text
- View/download PDF
36. Electronic Detection of DNA Hybridization by Coupling Organic Field-Effect Transistor-Based Sensors and Hairpin-Shaped Probes.
- Author
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Napoli C, Lai S, Giannetti A, Tombelli S, Baldini F, Barbaro M, and Bonfiglio A
- Abstract
In this paper, the electronic transduction of DNA hybridization is presented by coupling organic charge-modulated field-effect transistors (OCMFETs) and hairpin-shaped probes. These probes have shown interesting properties in terms of sensitivity and selectivity in other kinds of assays, in the form of molecular beacons (MBs). Their integration with organic-transistor based sensors, never explored before, paves the way to a new class of low-cost, easy-to-use, and portable genetic sensors with enhanced performances. Thanks to the peculiar characteristics of the employed sensor, measurements can be performed at relatively high ionic strengths, thus optimizing the probes' functionality without affecting the detection ability of the device. A complete electrical characterization of the sensor is reported, including calibration with different target concentrations in the measurement environment and selectivity evaluation. In particular, DNA hybridization detection for target concentration as low as 100 pM is demonstrated.
- Published
- 2018
- Full Text
- View/download PDF
37. Long-period fiber grating: a specific design for biosensing applications.
- Author
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Bandyopadhyay S, Biswas P, Chiavaioli F, Dey TK, Basumallick N, Trono C, Giannetti A, Tombelli S, Baldini F, and Bandyopadhyay S
- Abstract
In this paper, a detailed investigation on the modeling of long-period fiber grating (LPFG) sensors is discussed with the aim of providing a more realistic solution for their use in biosensing. Add-layer sensitivity, i.e., sensitivity of the sensor to an additional layer adhered onto the fiber surface, is quantified and a clear and complete analysis about the influence of the average thickness of the deposited biological sensing layers, as well as the change in refractive index of these layers, on the resonant wavelength of the cladding modes of an LPFG is provided. Add-layer sensitivity of LPFG sensors close to mode transition (MT) and also at turn-around point (TAP) are taken into account. Adsorbed layer thicknesses, as estimated from measured wavelength shifts of the LPFG, are found to have a good match with the values obtained through other measurement techniques.
- Published
- 2017
- Full Text
- View/download PDF
38. Molecular beacon-decorated polymethylmethacrylate core-shell fluorescent nanoparticles for the detection of survivin mRNA in human cancer cells.
- Author
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Adinolfi B, Pellegrino M, Giannetti A, Tombelli S, Trono C, Sotgiu G, Varchi G, Ballestri M, Posati T, Carpi S, Nieri P, and Baldini F
- Subjects
- A549 Cells, Biosensing Techniques methods, Humans, Nanoparticles ultrastructure, Optical Imaging methods, RNA Probes genetics, Spectrometry, Fluorescence methods, Survivin, Fluorescent Dyes chemistry, Inhibitor of Apoptosis Proteins genetics, Nanoparticles chemistry, Polymethyl Methacrylate chemistry, RNA Probes chemistry, RNA, Messenger analysis, RNA, Messenger genetics
- Abstract
One of the main goals of nanomedicine in cancer is the development of effective drug delivery systems, primarily nanoparticles. Survivin, an overexpressed anti-apoptotic protein in cancer, represents a pharmacological target for therapy and a Molecular Beacon (MB) specific for survivin mRNA is available. In this study, the ability of polymethylmethacrylate nanoparticles (PMMA-NPs) to promote survivin MB uptake in human A549 cells was investigated. Fluorescent and positively charged core PMMA-NPs of nearly 60nm, obtained through an emulsion co-polymerization reaction, and the MB alone were evaluated in solution, for their analytical characterization; then, the MB specificity and functionality were verified after adsorption onto the PMMA-NPs. The carrier ability of PMMA-NPs in A549 was examined by confocal microscopy. With the optimized protocol, a hardly detectable fluorescent signal was obtained after incubation of the cells with the MB alone (fluorescent spots per cell of 1.90±0.40 with a mean area of 1.04±0.20µm
2 ), while bright fluorescent spots inside the cells were evident by using the MB loaded onto the PMMA-NPs. (27.50±2.30 fluorescent spots per cell with a mean area of 2.35±0.16µm2 ). These results demonstrate the ability of the PMMA-NPs to promote the survivin-MB internalization, suggesting that this complex might represent a promising strategy for intracellular sensing and for the reduction of cancer cell proliferation., (Copyright © 2016 Elsevier B.V. All rights reserved.)- Published
- 2017
- Full Text
- View/download PDF
39. A Complete Optical Sensor System Based on a POF-SPR Platform and a Thermo-Stabilized Flow Cell for Biochemical Applications.
- Author
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Cennamo N, Chiavaioli F, Trono C, Tombelli S, Giannetti A, Baldini F, and Zeni L
- Abstract
An optical sensor platform based on surface plasmon resonance (SPR) in a plastic optical fiber (POF) integrated into a thermo-stabilized flow cell for biochemical sensing applications is proposed. This device has been realized and experimentally tested by using a classic receptor-analyte assay. For this purpose, the gold surface of the POF was chemically modified through the formation of a self-assembling monolayer. The surface robustness of the POF-SPR platform has been tested for the first time thanks to the flow cell. The experimental results show that the proposed device can be successfully used for label-free biochemical sensing. The final goal of this work is to achieve a complete, small-size, simple to use and low cost optical sensor system. The whole system with the flow cell and the optical sensor are extensively described, together with the experimental results obtained with an immunoglobulin G (IgG)/anti-IgG assay.
- Published
- 2016
- Full Text
- View/download PDF
40. Optical fiber nanotips coated with molecular beacons for DNA detection.
- Author
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Giannetti A, Barucci A, Cosi F, Pelli S, Tombelli S, Trono C, and Baldini F
- Subjects
- DNA chemistry, Nucleic Acid Hybridization, Biosensing Techniques methods, DNA analysis, Nanotechnology methods, Optical Fibers
- Abstract
Optical fiber sensors, thanks to their compactness, fast response and real-time measurements, have a large impact in the fields of life science research, drug discovery and medical diagnostics. In recent years, advances in nanotechnology have resulted in the development of nanotools, capable of entering the single cell, resulting in new nanobiosensors useful for the detection of biomolecules inside living cells. In this paper, we provide an application of a nanotip coupled with molecular beacons (MBs) for the detection of DNA. The MBs were characterized by hybridization studies with a complementary target to prove their functionality both free in solution and immobilized onto a solid support. The solid support chosen as substrate for the immobilization of the MBs was a 30 nm tapered tip of an optical fiber, fabricated by chemical etching. With this set-up promising results were obtained and a limit of detection (LOD) of 0.57 nM was reached, opening up the possibility of using the proposed nanotip to detect mRNAs inside the cytoplasm of living cells.
- Published
- 2015
- Full Text
- View/download PDF
41. Theranostic properties of a survivin-directed molecular beacon in human melanoma cells.
- Author
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Carpi S, Fogli S, Giannetti A, Adinolfi B, Tombelli S, Da Pozzo E, Vanni A, Martinotti E, Martini C, Breschi MC, Pellegrino M, Nieri P, and Baldini F
- Subjects
- Antineoplastic Agents pharmacology, Apoptosis drug effects, Apoptosis genetics, Cell Line, Tumor, DNA Fragmentation drug effects, Down-Regulation drug effects, Down-Regulation genetics, Gene Expression Regulation, Neoplastic genetics, Humans, Inhibitor of Apoptosis Proteins biosynthesis, Membrane Potential, Mitochondrial drug effects, Membrane Potential, Mitochondrial genetics, Oligonucleotide Probes genetics, Oligonucleotide Probes therapeutic use, RNA, Messenger genetics, RNA, Messenger metabolism, Substrate Specificity, Survivin, Inhibitor of Apoptosis Proteins genetics, Melanoma pathology, Oligonucleotide Probes metabolism
- Abstract
Survivin is an inhibitor of apoptosis overexpressed in different types of tumors and undetectable in most terminally differentiated normal tissues. In the current study, we sought to evaluate the in vitro theranostic properties of a molecular beacon-oligodeoxynucleotide (MB) that targets survivin mRNA. We used laser scanning confocal microscopy to study MB delivery in living cells and real-time PCR and western blot to assess selective survivin-targeting in human malignant melanoma cells. We further assess the pro-apoptotic effect of MB by measuring internucleosomal DNA fragmentation, dissipation of mitochondrial membrane potential (MMP) and changes in nuclear morphology. Transfection of MB into A375 and 501 Mel cells generated high signal intensity from the cytoplasm, while no signal was detected in the extracellular environment and in survivin-negative cells (i.e., human melanocytes and monocytes). MB time dependently decreased survivin mRNA and protein expression in melanoma cells with the maximum effect reached at 72 h. Treatment of melanoma cells with MB induced apoptosis by significant changes in MMP, accumulation of histone-complexed DNA fragments in the cytoplasm and nuclear condensation. MB also enhanced the pro-apoptotic effect of standard chemotherapeutic drugs tested at clinically relevant concentrations. The MB tested in the current study conjugates the ability of imaging with the pharmacological silencing activity against survivin mRNA in human melanoma cells and may represent an innovative approach for cancer diagnosis and treatment.
- Published
- 2014
- Full Text
- View/download PDF
42. Detection of clinically relevant point mutations by a novel piezoelectric biosensor.
- Author
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Dell'Atti D, Tombelli S, Minunni M, and Mascini M
- Subjects
- DNA analysis, DNA isolation & purification, DNA Mutational Analysis, Humans, Jurkat Cells, Polymerase Chain Reaction, Tumor Suppressor Protein p53 analysis, Tumor Suppressor Protein p53 isolation & purification, Biosensing Techniques, Point Mutation, Tumor Suppressor Protein p53 genetics
- Abstract
Piezoelectric sensing is here applied to point mutation detection in human DNA. The mutation investigated is in the TP53 gene, which results inactivated in most cancer types. TP53 gene maps on chromosome 17 (17p13.1). It contains 11 exons and codifies for the relative protein, involved in cell proliferation. The TP53 gene has a wide mutation spectrum that is related to different tumours. In particular, those occurring in the structurally important L2 and L3 zinc-binding domains, have been linked to patient prognosis and more strongly to radiotherapy and chemotherapy resistance in several major cancers. For this reason, the identification of these mutations represents an important clinical target and biosensors could represent good candidate for fast mutation screening. In this paper, a DNA-based piezoelectric biosensor for the detection of the TP53 gene mutation at codon 248 is reported. A biotinylated probe was immobilised on the sensor surface via dextran-streptavidin modified surfaces. The sensor was optimised using synthetic oligonucleotides. Finally, the sensor system was successfully applied to polymerase chain reaction (PCR)-amplified real samples of DNA extracted from two cell lines, one normal (wild-type) and one mutated, carrying the mutation at codon 248 of the TP53 gene. The results obtained demonstrate that the DNA-based piezoelectric biosensor is able to detect the point mutations in PCR-amplified samples showing the potentialities of this approach for routine analysis.
- Published
- 2006
- Full Text
- View/download PDF
43. Immobilisation of DNA probes for the development of SPR-based sensing.
- Author
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Wang R, Tombelli S, Minunni M, Spiriti MM, and Mascini M
- Subjects
- Adsorption, Biosensing Techniques instrumentation, Coated Materials, Biocompatible chemistry, In Situ Hybridization instrumentation, Surface Plasmon Resonance instrumentation, Biosensing Techniques methods, DNA analysis, DNA chemistry, DNA Probes chemistry, In Situ Hybridization methods, Polymerase Chain Reaction methods, Surface Plasmon Resonance methods
- Abstract
An immobilisation procedure based on the direct coupling of thiol-derivatised oligonucleotide probes to bare gold sensor surfaces has been used for DNA sensing applications. The instrumentation used relies on surface plasmon resonance (SPR) transduction; in particular the commercially available instruments BIACORE X and SPREETA, have been employed in this study. The performances of the SPR-based DNA sensors resulting from direct coupling of thiol-derivatised DNA probes onto gold chips, have been studied in terms of the main analytical parameters, i.e. selectivity, sensitivity, reproducibility, analysis time, etc. A comparison between the thiol-derivatised immobilisation approach and a reference immobilisation method, based on the coupling of biotinylated oligonucleotide probes onto a streptavidin coated dextran sensor surface, using synthetic complementary oligonucleotides has been discussed. Finally, a denaturation method to obtain ssDNA ready for hybridisation analysis has been applied to polymerase chain reaction (PCR) amplified samples, for the detection of genetically modified organisms (GMOs).
- Published
- 2004
- Full Text
- View/download PDF
44. A new approach for the detection of DNA sequences in amplified nucleic acids by a surface plasmon resonance biosensor.
- Author
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Wang R, Minunni M, Tombelli S, and Mascini M
- Subjects
- Apolipoproteins E analysis, Apolipoproteins E genetics, Biosensing Techniques instrumentation, DNA, Plant analysis, DNA, Plant genetics, Humans, Oligonucleotide Array Sequence Analysis instrumentation, Polymerase Chain Reaction instrumentation, Surface Plasmon Resonance instrumentation, Zea mays genetics, Biosensing Techniques methods, DNA analysis, DNA genetics, Oligonucleotide Array Sequence Analysis methods, Polymerase Chain Reaction methods, Surface Plasmon Resonance methods
- Abstract
In this paper, a simple and useful approach for DNA sensing based on surface plasmon resonance (SPR) transduction is reported. A new DNA sample pre-treatment has been optimised to allow fast and simple detection of hybridisation reaction between a target sequence in solution and a probe immobilised on the sensing surface. This pre-treatment consisted in a denaturation procedure of double stranded DNA containing the target sequence and was based on an high temperature treatment (95 degrees C, 5 min) followed by a 1 min incubation with small oligonucleotides. The oligonucleotides are designed to prevent the re-hybridising of the denatured strands, while enabling the target sequence to bind the immobilised probe. The important parameters of the procedure, i.e. incubation time, length and concentration of the oligonucleotides, have been studied in detail. The optimised DNA denaturation procedure has been successfully applied to the detection of amplified DNA with a commercially available SPR biosensor (Biacore X). DNA samples extracted from plant and human blood were tested after amplification by polymerase chain reaction (PCR).
- Published
- 2004
- Full Text
- View/download PDF
45. Combination of amplification and post-amplification strategies to improve optical DNA sensing.
- Author
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Giakoumaki E, Minunni M, Tombelli S, Tothill IE, Mascini M, Bogani P, and Buiatti M
- Subjects
- DNA genetics, DNA Probes chemical synthesis, Nucleic Acid Amplification Techniques methods, Nucleic Acid Denaturation, Optics and Photonics, Reproducibility of Results, Sensitivity and Specificity, Biosensing Techniques methods, DNA analysis, DNA chemistry, DNA Probes chemistry, Polymerase Chain Reaction methods, Surface Plasmon Resonance methods
- Abstract
The work evaluated a series of approaches to optimise detection of polymerase chain reaction (PCR) amplified DNA samples by an optical sensor based on surface plasmon resonance (SPR) (BiacoreX). The optimised procedure was based on an asymmetric PCR amplification system to amplify predominantly one DNA strand, containing the sequence complementary to a specific probe. The study moved into two directions, aiming to improve the analytical performance of SPR detection in PCR amplified products. One approach concerned the application of new strategies at the level of PCR, i.e. asymmetric PCR to obtain ssDNA amplified fragments containing the target capable of hybridisation with the immobilised complementary probe. The other strategy focused on the post-PCR amplification stage. Optimised denaturing conditions were applied to both symmetrically and asymmetrically amplified fragments. The effective combination of the two strategies allowed a rapid and specific hybridisation reaction. The developed method was successfully applied in the detection of genetically modified organisms.
- Published
- 2003
- Full Text
- View/download PDF
46. Quartz crystal microbalance (QCM) affinity biosensor for genetically modified organisms (GMOs) detection.
- Author
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Mannelli I, Minunni M, Tombelli S, and Mascini M
- Subjects
- Affinity Labels, Agrobacterium tumefaciens genetics, Biosensing Techniques methods, Caulimovirus genetics, Coated Materials, Biocompatible chemical synthesis, Crystallization instrumentation, Crystallization methods, DNA standards, DNA, Ribosomal analysis, Electrochemistry instrumentation, Electrochemistry methods, Equipment Design, Food Contamination analysis, Microelectrodes, Polymerase Chain Reaction methods, Quality Control, Quartz, Reproducibility of Results, Sensitivity and Specificity, Biosensing Techniques instrumentation, DNA analysis, DNA Probes, Organisms, Genetically Modified genetics, Transducers
- Abstract
A DNA piezoelectric sensor has been developed for the detection of genetically modified organisms (GMOs). Single stranded DNA (ssDNA) probes were immobilised on the sensor surface of a quartz crystal microbalance (QCM) device and the hybridisation between the immobilised probe and the target complementary sequence in solution was monitored. The probe sequences were internal to the sequence of the 35S promoter (P) and Nos terminator (T), which are inserted sequences in the genome of GMOs regulating the transgene expression. Two different probe immobilisation procedures were applied: (a) a thiol-dextran procedure and (b) a thiol-derivatised probe and blocking thiol procedure. The system has been optimised using synthetic oligonucleotides, which were then applied to samples of plasmidic and genomic DNA isolated from the pBI121 plasmid, certified reference materials (CRM), and real samples amplified by the polymerase chain reaction (PCR). The analytical parameters of the sensor have been investigated (sensitivity, reproducibility, lifetime etc.). The results obtained showed that both immobilisation procedures enabled sensitive and specific detection of GMOs, providing a useful tool for screening analysis in food samples.
- Published
- 2003
- Full Text
- View/download PDF
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