Nicoletta Giamblanco | University of Montpellier (original) (raw)

Papers by Nicoletta Giamblanco

HAL (Le Centre pour la Communication Scientifique Directe), 2021

HAL (Le Centre pour la Communication Scientifique Directe), 2020

Mussel wet adhesion is known for its outstanding strength on a variety of surfaces. Based on the ... more Mussel wet adhesion is known for its outstanding strength on a variety of surfaces. Based on the hypothesis that 3,4-dihydroxyphenylalanine, a catecholic amino acid, governs mussel adhesion, chemists have put much effort into the design of adhesive synthetic polymers containing catechols. However, the exceptional properties exhibited by the native proteins were hardly captured. The attempts to make those polymers stick to wet inorganic surfaces resulted in low adhesive forces. Here we synthesized poly(dopamine acrylamide) and measured the interaction forces with various inorganic surfaces using AFM-based single-molecule force spectroscopy. We show that hydroxylation of the surface plays a pivotal role on the formation of strong bonds. We demonstrate that depending on the conditions, the whole range of interactions, from weak interactions to covalent bonds, can come into play.

Figure S-1. Current voltage (I-V) curves before (black, square) and after functionalization with ... more Figure S-1. Current voltage (I-V) curves before (black, square) and after functionalization with the PEG 5k (red, square) in 1.0 M KCl at pH 5.6 for the NP (rbase 115 nm and r t 11 nm).

The modification of AFM tips is based on the electro-initiated synthesis of poly-N-succinimidylac... more The modification of AFM tips is based on the electro-initiated synthesis of poly-N-succinimidylacrylate. This very simple one-step 'grafting-from' process results in the direct chemisorption of polymer chains onto the tip surface (Figure 1). The activated esters along the polymer backbone pave the way to further easy functionalization at room temperature both in water and in organic solvents. This is an ideal basis for the one-step anchoring of a wide range of nucleophilic compounds like amino groups. We have chosen grafting conditions resulting in an isolated chain regime, so that only one or very few polymeric linkers are tethered to the tip apex. . Dopamine molecules, which are bio-inspired adhesives, were then bonded to the polymer backbone via an amide link, leading to macromolecules bearing catechol groups.

a. Institut Européen des Membranes, UMR5635, Université de Montpellier CNRS ENSCM, Place Eugène B... more a. Institut Européen des Membranes, UMR5635, Université de Montpellier CNRS ENSCM, Place Eugène Bataillon, 34090 Montpellier, France b. Laboratoire des Solides Irradiés, École polytechnique, Université Paris-Saclay,Route de Saclay, 91128 Palaiseau Cedex, France c. Institut d’Electronique et des Systèmes, Université de Montpellier, 34095 Montpellier Cedex 5, France * diego.coglitore@umontpellier.fr

Small Methods, 2020

from β-lactoglobulin show several interesting features, such as the high aspect ratio (length vs ... more from β-lactoglobulin show several interesting features, such as the high aspect ratio (length vs diameter) making them a structuring agent in foods, stabilizers of foam and in emulsions as well as building blocks of microcapsules. [8] The applications of β-lactoglobulin fibrils in food products require a deep understanding of fibril digestion processes occurring during passage through the stomach and the intestine. [9] Indeed, certain amyloids such as tau, α-synuclein or β-peptides are involved in neurodegenerative diseases. [10] The protein fibril digestion can cleave the fibrils to oligomers with a potential increased pathogenic [11,12] or contribute to the formation of new fibrils as seeds. [13] To date, the investigation of the nondisease-related amyloid-like fibrils degradation combining kinetic and identification of species are difficult due to the difficulty to obtain both information using the same technique. Nanopore technology is one of the most promising approaches to protein sensing. [14,15] It allows single molecule detection providing information about the size, shape as well as charge. [16,17,18] Nanopores are also a platform to characterize the protein conformational change including folding/ unfolding. [19] Biological nanopores take advantage of their precise structure, allowing the characterization of polypeptide length and the identification of amino-acids, [20] opening a new avenue for protein sequencing. [21,22] On the other hand, they were used to detect small oligomers of peptides [23] and antibody prion interactions. [24] Solid-state nanopores and nanopipettes allow the characterization of the protein and peptide oligomerization giving also information on their morphology. [25] This makes them a candidate to develop new analytical tools for amyloid sensing. [26] However, their diameter and their short lifetime don't allow protofibril detection nor long time analysis. We recently reported that conical track-etched nanopore is likely the most suitable candidate to investigate the protein aggregation from small aggregates to protofibrils scale. [27] In this report, β-lactoglobulin aggregation was studied, discriminating between oligomer and protofibril populations. In addition, the long nanopore lifetime and the possibility to perform long time experiments, is suitable to analyze the digestion of β-lactoglobulin aggregates. The most relevant physiological proteases in digestion process are pepsin (stomach) and trypsin (small intestine). β-lactoglobulin aggregates are used as structuring agents in food processing. Their enzymatic degradation follows different pathways depending on the enzyme and the pH. The transient species produced during the degradation process are difficult to characterize under continuous measurement. Here, conical track-etched nanopores are used to investigate the β-lactoglobulin degradation by pepsin (pH 2) and trypsin (pH 9). Before enzyme addition, two distinct populations, oligomers and protofibrils, are identified. Just after enzyme addition, the aggregate size decreases. For pepsin, a phenomenon of reaggregation that does not occur for the trypsin is evidenced. In addition, after 140 min a larger population of aggregate appears. The experimental results are supported by a kinetic model. This work also demonstrates that conical nanopore allows following the kinetic of transient protein aggregate intermediates during enzymatic degradation.

Sensors and Actuators B: Chemical, 2018

Highlights  3 protein amyloids (Lysozyme, β-lactoblogulin and BSA) translocation through a SiNx ... more Highlights  3 protein amyloids (Lysozyme, β-lactoblogulin and BSA) translocation through a SiNx single nanopore  Nanopore functionalized by PEG allows preventing protein aggregate adsorption  The intensity of relative current blockade allows to discriminate the morphology of proteins aggregates

Biophysical Journal, 2018

accessible synthetic nanopore fabrication approach, controlled breakdown (CDB). Since CDB uses co... more accessible synthetic nanopore fabrication approach, controlled breakdown (CDB). Since CDB uses conductance feedback to monitor the nanopore fabrication, it cannot tell whether there is a large single nanopore or multiple small nanopores in the membrane. In this work, we found that despite the stochastic process during the breakdown, nanopores created via breakdown in a SiN x membrane tend to have the same scale. We proposed a resistance model to govern the multiple nanopores formation by the conductance feedback-the number of nanopores in the membrane was determined by the membrane resistance and the nanopore sizes were controlled by the enlargement electric field. We further characterized our multiple nanopores by transmission electron microscopy (TEM) imaging and the fluorescence of Ca 2þ-activated dyes. We anticipate that by combining with optical measurements, this fabrication approach could accelerate the process of nanopore sensing towards a highthroughput and multichannel technique.

Analytical Chemistry, 2018

Amyloid fibrils are involved in several neurodegenerative diseases. However due to their 15 polym... more Amyloid fibrils are involved in several neurodegenerative diseases. However due to their 15 polymorphism and low concentration, they are challenging to assess in real-time with 16

Physical chemistry chemical physics : PCCP, Jan 9, 2018

Solid-state nanopore technology for nanoparticle sensing is considered for the development of ana... more Solid-state nanopore technology for nanoparticle sensing is considered for the development of analytical tools to characterise their size, shape or zeta potential. In this field, it is crucial to understand how the nanopore inner surface influences the dynamic of nanoparticle translocation. Here, three single nanopores directly drilled in metal alloys (titanium nitride, titanium-tantalum and tantalum) are considered. The translocation of polystyrene nanoparticles coated with ssDNA is investigated by the resistive pulse method at different concentrations and voltages. The results show that the nanoparticle energy barrier for entrance into the pore decreases for nanopores that exhibits a higher surface energy and hydrophilicity, while the dwell time is found to depend on the nanopore surface state. Overall, this study demonstrates that the control of nanopore surface state must be taken into account for the resistive pulse experiments for nanoparticle detection.

Langmuir : the ACS journal of surfaces and colloids, Jan 13, 2018

The understanding of the interactions between nanomaterials, biomolecules and polyphenols is fund... more The understanding of the interactions between nanomaterials, biomolecules and polyphenols is fundamental in food chemistry, toxicology and new emerging fields such as nanomedicine. Here we investigated the effect of the resveratrol, a principal actor in drug delivery application on the interaction between BSA, employed as a vector for the delivery of polyphenol drugs, and gold nanoparticle (gNP), the most promising tool in theranostic applications. Through a combination of experimental techniques, which includes an initial evaluation by dynamic light scattering and surface plasmon resonance spectroscopy, we were able to evaluate the evolution of the gold nanoparticle aggregation with increasing ionic strength and the consequences of the BSA and resveratrol addition. In order to investigate the mechanisms of the interactions, we pursued at the single-molecule level using solid-state nanopore and fluorescence correlation spectroscopy. Our results show that without resveratrol the BSA ...

Atomic force microscopy (AFM)-based single-molecule force spectroscopy is a prevalent tool for th... more Atomic force microscopy (AFM)-based single-molecule force spectroscopy is a prevalent tool for the exploration of individual (bio)molecules, providing exquisite information on many molecular-level processes. For example, proteins, DNA, polysaccharides, supramolecular polymers and polyelectrolytes have been investigated, revealing details about the strength of intramolecular interactions, folding and unfolding pathways, mechanics, conformational changes, reactivity, kinetics, etc. For each particular system under investigation, the experimental design is a decisive phase that often involves a multistep chemical protocol, including grafting, derivatization, coupling, (de-)protection, and other functionalization reactions. Procedures of sample preparation are often complex and time-consuming. Hence, there is a need for new general platforms allowing for straightforward sample preparation adapted to single-molecule studies, i.e. a tight attachment to both the substrate and the tip, and a low density to favor single-molecule detection. We report here on the use of poly(ethylene oxide) (PEO) as a tether to probe various properties of individual molecules. The polymeric linker acts as a handle that stably binds to the AFM tip. The simple adsorption of poly(ethylene oxide) to the tip is versatile and provides an appropriate system configuration for the investigation of many different biological and synthetic molecular systems. To attest for this versatility and adequacy with advanced single-molecule investigation, we present different examples of PEO-mediated studies about the unfolding of a synthetic peptide, the mechanochemical behavior of a molecular machine and finally the stability of a metallo-supramolecular complexed polymer. All the requirements for the study of peptide conformation, tiny molecular machines or metallo-supramolecular interactions in solution are here fulfilled. More generally, this method based on non-covalent sorption of PEO on an AFM tip, can be implemented in a wide range of solvents, for the study of many intra- or intermolecular phenomena at the single-molecule level over orders of magnitude of force loading rates. Connecting PEO tethers to a very broad variety of (bio)molecules is a facile and versatile route. The commercial availability of many different functional PEOs makes this tethering strategy even more accessible

Nanoscale, Jan 26, 2018

Experimental and theoretical reports have shown that nanostructured surfaces have a dramatic effe... more Experimental and theoretical reports have shown that nanostructured surfaces have a dramatic effect on the amount of protein adsorbed and the conformational state and, in turn, on the performances of the related devices in tissue engineering strategies. Here we report an innovative method to prepare silica-based nanostructured surfaces with a reproducible, well-defined local curvature, consisting of ordered hexagonally packed arrays of curved hemispheres, from nanoparticles of different diameters (respectively 147 nm, 235 nm and 403 nm). The nanostructured surfaces have been made chemically homogeneous by partially embedding silica nanoparticles in poly(hydroxymethylsiloxane) films, further modified by means of UV-O3 treatments. This paper has been focused on the experimental and theoretical study of laminin, taken as a model protein, to study the nanocurvature effects on the protein configuration at nanostructured surfaces. A simple model, based on the interplay of electrostatic in...

ACS Omega, 2017

Recent surveys have shown that the number of nanoparticle-based formulations actually used at a c... more Recent surveys have shown that the number of nanoparticle-based formulations actually used at a clinical level is significantly lower than that expected a decade ago. One reason for this is that the physicochemical properties of nanoparticles fall short for handling the complexity of biological environments and preventing nonspecific protein adsorption. In this study, we address the issue of the interactions of plasma proteins with polymer-coated surfaces. With this aim, we use a noncovalent grafting-to method to functionalize iron oxide sub-10 nm nanoparticles and iron oxide flat substrates and compare their protein responses. The functionalized copolymers consist of alternating poly(ethylene glycol) (PEG) chains and phosphonic acid grafted on the same backbone. Quartz crystal microbalance with dissipation was used to monitor polymer adsorption kinetics and evaluate the resistance to protein adsorption. On flat substrates, functionalized PEG copolymers adsorb and form a brush in moderate or highly stretched regimes, with densities between 0.15 and 1.5 nm −2. PEG layers using phosphonic acid as linkers exhibit excellent protein resistance. In contrast, layers prepared with carboxylic acid as the grafting agent exhibit mitigated protein responses and layer destructuration. The present study establishes a correlation between the long-term stability of PEG-coated particles in biofluids and the protein resistance of surfaces coated with the same polymers.

Journal of Colloid and Interface Science, 2017

Clinical application of DNA microarrays used for screening of single nucleotide polymorphisms (SN... more Clinical application of DNA microarrays used for screening of single nucleotide polymorphisms (SNPs) are very important for diagnosis of diseases and appropriate treatment of patients. In this paper localized surface plasmon resonance (LSPR) technique has been used to study the DNA hybridization process for binary solutions of respectively perfectly matching (PM) and single base mismatching (MM) 93-mer ssDNA from KRAS codon 12. 5 0-thiol modified 35-mer ssDNA has been linked to the Au nanodisks array as probe with a surface coverage of 2.8 ± 0.1 Â 10 12 /cm 2. Probe's binding properties was investigated in details, obtaining a sensitivity down to 10 nM and 13 nM, respectively for PM and MM, showing that the hybridization process occurs at a lower rate for MM with respect to PM target. The competitive hybridization is accounted for by an inhibition model, where the non-complementary sequences kinetically hinder the hybridization of the perfect matching sequences, owing to their above mentioned affinity constant differences for the same probe. Accordingly, the single nucleotide polymorphisms can therefore be revealed in a single step and label free mode with high sensitivity and specificity by LSPR measurements.