Search publications 


CVD-grown Graphene-on-Au characterization and sensing using Kretschmann-based SPR

Publication year: 2020
Authors: Jamil N.A.1, Mei G.S.1, Zain A.R. 1,2, Hewak D. 3, Huang C-C. 3, Mohamed M.A. 1, Majlis B.Y. 1, Menon P.S.1,*
Published in: Electron Devices Technology and Manufacturing Conference (EDTM), IEEE
A Kretschmann-based surface plasmon resonance (SPR) sensing method was used to determine the refractive index and thickness of graphene thin films. The measured complex refractive index (n,k) values of graphene on Au at 670 nm and 785 nm wavelength are 2.85, 0.74 and 3.1, 1.19 respectively. In further analysis, the analysis of sensing performance of graphene on Au SPR sensor for ethanol detection was obtained using Finite Difference Time Domain (FDTD) method.[...]

Surfactant Interactions with Protein-Coated Surfaces: Comparison between Colloidal and Macroscopically Flat Surfaces

Publication year: 2020
Authors: Mateos H. 1,*, Valentini A. 2, Lopez F. 3, Palazzo G. 4
Published in: Biomimetics 2020, Vol. 5(3), p. 31
Surface interactions with polymers or proteins are extensively studied in a range of industrial and biomedical applications to control surface modification, cleaning, or biofilm formation. In this study we compare surfactant interactions with protein-coated silica surfaces differing in the degree of curvature (macroscopically flat and colloidal nanometric spheres). The interaction with a flat surface was probed by means of surface plasmon resonance (SPR) while dynamic light scattering (DLS) was used to study the interaction with colloidal SiO2 (radius 15 nm).Surface interactions with polymers or proteins are extensively studied in a range of industrial and biomedical applications to control surface modification, cleaning, or biofilm formation. In this study we compare surfactant interactions with protein-coated silica surfaces differing in the degree of curvature (macroscopically flat and colloidal nanometric spheres). The interaction with a flat surface was probed by means of surface plasmon resonance (SPR) while dynamic light scattering (DLS) was used to study the interaction with colloidal SiO2 (radius 15 nm).[...]

PEDOT-polyamine composite films for bioelectrochemical platforms -flexible and easy to derivatize

Publication year: 2020
Authors: Sappia L. +a, Piccinini E. +a, von Binderling C. a, Knoll W. bcd, Marmisollé W. *a, Azzorini O. *acd
Published in: Material Sciece and Engineering: C, 2020, Vol. 109, p.110575
We report a straightforward route for the preparation of flexible, electrochemically stable and easily functionalizable poly(3,4-ethylenedioxythiophene) (PEDOT) composite films deposited on PET foils as biosensing platforms. For this purpose, poly(allylamine) hydrochloride (PAH) was blended with PEDOT to provide amine-bearing sites for further biofunctionalization as well as to improve the mechanical properties of the films.[...]

Modulation of Living Cell Behavior with Ultra‐Low Fouling Polymer Brush Interfaces

Publication year: 2020
Authors: Víšová I., Smolková B., Uzhytchak M., Vrabcová M., Zhigunova Y., Houska M. ,Surman F., de los Santos Pereira A.,Lunov O., Dejneka A., Vaisocherová‐Lísalová H.
Published in: Macromolecular Bioscience, 2020, Vol. 20, 3, p. 1900351
Ultra‐low fouling and functionalizable coatings represent emerging surface platforms for various analytical and biomedical applications such as those involving examination of cellular interactions in their native environments. Ultra‐low fouling surface platforms as advanced interfaces enabling modulation of behavior of living cells via tuning surface physicochemical properties are presented and studied.[...]

Surface Preconditioning Influences the Antifouling Capabilities of Zwitterionic and Nonionic Polymer Brushes

Publication year: 2020
Authors: Víšová I. 1, Vrabcová M. 1, Forinová M. 1, Zhigunová Y. 1, Mironov V. 1, Houska . 1, Bittrich E. 2, Eichhorn K. 2, Hashim H. 3,4, Schovánek P. 1,5, Dejneka A. 1, Vaisocherová - Lísalová H. 1
Published in: Langmuir, 2020, Vol. 36, 29, 8485–8493
Polymer brushes not only represent emerging surface platforms for numerous bioanalytical and biological applications but also create advanced surface-tethered systems to mimic real-life biological processes. In particular, zwitterionic and nonionic polymer brushes have been intensively studied because of their extraordinary resistance to nonspecific adsorption of biomolecules (antifouling characteristics) as well as the ability to be functionalized with bioactive molecules.[...]

Delineating the Molecular Basis of the Calmodulin–bMunc13-2 Interaction by Cross-Linking/Mass Spectrometry—Evidence for a Novel CaM Binding Motif in bMunc13-2

Publication year: 2020
Authors: Piotrowski C. 1, Moretti R. 2, Ihling C. 1,Haedicke A. 3†, Liepold T. 4, Lipstein N. 5, Meiler J. 2, Jahn O. 4,*, Sinz A. 1,*
Published in: Cells, 2020, Vol.9 (1) , p.136
Exploring the interactions between the Ca2+ binding protein calmodulin (CaM) and its target proteins remains a challenging task. Members of the Munc13 protein family play an essential role in short-term synaptic plasticity, modulated via the interaction with CaM at the presynaptic compartment. [...]

Functional Plasma Polymerized Surfaces for Biosensing

Publication year: 2020
Authors: Makhneva* E., Barillas L 1., Farka Z. 2, Pastucha M. 2, Skládal P. 2, Weltmann K.D. 1, Fricke K. 1
Published in: Applied Material Interfaces, 2020, Vol.12, 14, p.17100–17112
The capabilities of biosensors for fast, economic, and user-friendly analysis of complex samples has led to the exploitation of analytical devices for detection, quantification, and monitoring of specific chemical species for various applications. For a sufficiently high surface reactivity toward the adopted bioreceptors, a thin functional layer is required to enable coupling of the target biomolecules and to provide good stability in the presence of a sample matrix.[...]

Single-vesicle imaging reveals lipid-selective and stepwise membrane disruption by monomeric α-synuclein

Publication year: 2020
Authors: Hannestad J. a, Rocha S. b, Agnarsson B. a, Zhdanov V. ac, Wittung-Stafshede P. *b, Höök F. *a
Published in: Proceedings of National Academy of Sciences PNAS, 2020, Vol. 117, 25, p.14178-14186
The interaction of the neuronal protein α-synuclein with lipid membranes appears crucial in the context of Parkinson’s disease, but the underlying mechanistic details, including the roles of different lipids in pathogenic protein aggregation and membrane disruption, remain elusive. Here, we used single-vesicle resolution fluorescence and label-free scattering microscopy to investigate the interaction kinetics of monomeric α-synuclein with surface-tethered vesicles composed of different negatively charged lipids.[...]

Enhancing the Sensitivity of Biotinylated Surfaces by Tailoring the Design of the Mixed Self-Assembled Monolayer Synthesis

Publication year: 2020
Authors: Blasi D. ‡†, Sarcina L. ‡§, Tricase A. ‡§, Stefanachi A. ‖, Leonetti F.*‖, Alberga D. $, Mangiatordi* Ͱ, Manoli K. †§, Scamarcio G. ◊∫, Picca R.A. *†§, Torsi L. †§#
Published in: ACS Omega 2020, Vol. 5, 27, p. 16762–16771
Thiolated self-assembled monolayers (SAMs) are typically used to anchor on a gold surface biomolecules serving as recognition elements for biosensor applications. Here, the design and synthesis of N-(2-hydroxyethyl)-3-mercaptopropanamide (NMPA) in biotinylated mixed SAMs is proposed as an alternative strategy with respect to on-site multistep functionalization of SAMs prepared from solutions of commercially available thiols.[...]

Label-free characterization and real-time monitoring of cell uptake of extracellular vesicles

Publication year: 2020
Authors: Koponen A.ab, Kerkelä E. a, Rojalin T. b, Lázaro-Ibáñez E. b, Suutari T. b, Saari H.b, Siljander P.c, Yliperttula M. b, Laitinen S. a, Viitala T. b
Published in: Biosensors and Bioelectronics, 2020, Vol. 168, p. 112510
Extracellular vesicles (EVs) have the ability to function as molecular vehicles and could therefore be harnessed to deliver drugs to target cells in diseases such as cancer. The composition of EVs determines their function as well as their interactions with cells, which consequently affects the cell uptake efficacy of EVs.[...]

Nickel (II) phthalocyanine-tetrasulfonic-Au nanoparticles nanocomposite film for tartrazine electrochemical sensing

Publication year: 2020
Authors: de Lima L. 1, Maciel C. 2, Ferreira A. 1, de Almeida J. 2, Ferreira M. 1*
Published in: Materials Letters, 2020 Vol. 262, p. 127186
In this work, we report the analytical detection of tartrazine through differential pulse voltammetry (DPV) using gold nanoparticles (AuNPs) and Nickel(II)-phthalocyanine-tetrasulfonic (NiTsPc). The Layer-by-Layer (LbL) film was constructed following the Au-(AuNPs-PAH/NiTsPc)5 architecture.[...]

Heparin/Collagen Surface Coatings Modulate the Growth, Secretome and Morphology of Human Mesenchymal Stromal Cell Response to Interferon‐Gamma

Publication year: 2020
Authors: Cifuentes S. 1, Priyadarshani P. 23,Castilla‐Casadiego D. 4, Mortensen L. 23,Almodóvar J. 4, Domenech M. 15
Published in: Journal of Biomedical Materials Research, 2020
The therapeutic potential of human mesenchymal stromal cells (h‐MSC) is dependent on the viability and secretory capacity of cells both modulated by the culture environment. Our previous studies introduced heparin and collagen I (HEP/COL) alternating stacked layers as a potential substrate to enhance the secretion of immunosuppressive factors of h‐MSCs. [...]

Layer-by-Layer nanostructured films of magnetite nanoparticles and polypyrrole towards synergistic effect on methylparaben electrochemical detection

Publication year: 2020
Authors: de Lima L., Daikuzono C., Miyazaki C., Pereira E., Ferreira M.*
Published in: Applied Surface Science 2020, Vol. 505, p. 144278
The sustained use of cosmetics, hygiene products and medicines containing methylparaben (MeP) can be related to cases of cancer in women and children, which is why it is important to develop simple ways to monitor this compound. Gold electrodes were modified with Layer-by-Layer (LbL) films of magnetite nanoparticles (MNP) and polypyrrole (Ppy) for electrochemical determination of MeP.[...]

Partitioning of Catechol Derivatives in Lipid Membranes: Implications for Substrate Specificity to Catechol-O-methyltransferase

Publication year: 2020
Authors: Parkkila P., Viitala T.
Published in: ACS Chemical Neuroscience, 2020, Vol.11, 6, p. 969–978
We have utilized multiparametric surface plasmon resonance and impendance-based quartz crystal microbalance instruments to study the distribution coefficients of catechol derivatives in cell model membranes. Our findings verify that the octanol–water partitioning coefficient is a poor descriptor of the total lipid affinity for small molecules which show limited lipophilicity in the octanol–water system.[...]

An investigation of the synergistic effect between magnetite nanoparticles and polypyrrole in nanostructured layer‐by‐layer films

Publication year: 2020
Authors: de Lima L. 1,2, Maciel C. 3, Ferreira A. 1, Rubira R. 4, Constantino C. 4, Ferreira M. *1 1M.
Published in: Journal of Applied Polymer Science, 2020
In this paper, we report the controlled fabrication of layer‐by‐layer (LbL) films deposited on gold substrates with three different supramolecular architectures using polypyrrole (Ppy) and magnetite nanoparticles (Fe3O4‐np), besides conventional poly(allylamine hydrochloride) (PAH) e poly(vinyl sulfonic acid) (PVS) polyelectrolytes, demonstrating the synergistic effect between Ppy and Fe3O4‐np such as a result of their interaction.[...]

Diffusion and Protein Corona Formation of Lipid-Based Nanoparticles in the Vitreous Humor: Profiling and Pharmacokinetic Considerations

Publication year: 2020
Authors: Tavakoli S 1., Kari O.K. 1, Turunen T. 1, Lajunen T. 1, Schmitt M. 1, Lehtinen J. 1, Tasaka F. 2, Parkkila P. 1, Ndika J. 3, Viitala T. 1, Alenius H. 3,5, Urtti, A. 1,6,7 Subriz A. *7
Published in: Molecular Pharmaceutics, 2020
The vitreous humor is the first barrier encountered by intravitreally injected nanoparticles. Lipid-based nanoparticles in the vitreous are studied by evaluating their diffusion with single-particle tracking technology and by characterizing their protein coronae with surface plasmon resonance and high-resolution proteomics. Single-particle tracking results indicate that the vitreal mobility of the formulations is dependent on their charge.[...]

Ultra-low HIV-1 p24 detection limits with a bioelectronic sensor

Publication year: 2020
Authors: Macchia E. 12, Sarcina L. 1, Picca R.A. 1, Manoli K. 1, Di Franco C. 1, Scamarcio G. 34 Torsi L. 125
Published in: Analytical and Bioanalytical Chemistry, 2020, Vol. 412, p. 811–818
Early diagnosis of the infection caused by human immunodeficiency virus type-1 (HIV-1) is vital to achieve efficient therapeutic treatment and limit the disease spreading when the viremia is at its highest level. To this end, a point-of-care HIV-1 detection carried out with label-free, low-cost, and ultra-sensitive screening technologies would be of great relevance.[...]

Mechanism of lysozyme adsorption onto gold surface determined by quartz crystal microbalance and surface plasmon resonance

Publication year: 2020
Authors: Komorek P., Wałek M., Jachimska B.
Published in: Bioelectrochemistry, 2020, Vol. 135, p. 107582
In this study, the physicochemical characterization of lysozyme adsorbed on gold was investigated. Through the use of MP-SPR it was possible to establish that the orientation of molecules changes from side-on to between or end-on with increasing surface coverage.[...]

Assessment of Gold Bio-Functionalization for Wide-Interface Biosensing Platforms

Publication year: 2020
Authors: Sarcina L. 1,Torsi L. 123, Picca R.A. 12, Manoli K. 12*, Macchia E. 3
Published in: Sensors, 2020, Vol. 20, p. 3678
The continuous improvement of the technical potential of bioelectronic devices for biosensing applications will provide clinicians with a reliable tool for biomarker quantification down to the single molecule. Eventually, physicians will be able to identify the very moment at which the illness state begins, with a terrific impact on the quality of life along with a reduction of health care expenses.[...]

Comparative Characterization of Plasmodium falciparum Hsp70-1 Relative to E. coli DnaK Reveals the Functional Specificity of the Parasite Chaperone

Publication year: 2020
Authors: Lebepe C. 1, Matambanadzo P. 1, Makhoba X. 2, Achilonu I. 3, Zininga T. 1,4, Shonhai A. 1,*
Published in: Biomolecules 2020, Vol. 10(6), p. 856
Hsp70 is a conserved molecular chaperone. How Hsp70 exhibits specialized functions across species remains to be understood. Plasmodium falciparum Hsp70-1 (PfHsp70-1) and Escherichia coli DnaK are cytosol localized molecular chaperones that are important for the survival of these two organisms. [...]