Laura Sola

Italian National Research Council | CNR · Istituto di Scienze e Tecnologie Chimiche "Giulio Natta"-SCITEC CNR

We report here a deep investigation into the effect of the concentration of a polymeric coating’s functional groups on probe density immobilization with the aim of establishing the optimal formulation to be implemented in specific microarray applications. It is widely known that the ideal performance of a microarray strictly depends on the way prob...

Serological assays enable infection screening as relatively easy-to-operate approaches compared with standard methods. In addition, to be relevant for early diagnosis, specific antibody detection is important for epidemiological surveillance and quantitative detection has potential significance for evaluating the severity and prognosis of different...

The analytical performance of the microarray technique in screening the affinity and reactivity of molecules toward a specific target is highly affected by the coupling chemistry adopted to bind probes to the surface. However, the surface functionality limits the biomolecules that can be attached to the surface to a single type of molecule, thus fo...

Tangential flow filtration membrane systems are employed for the isolation and concentration of extracellular vesicles. However, interfacial interactions between the membrane surface and species influence the flux and membrane performance. Here we propose a strategy aimed at introducing functional ligands over the membrane surface to improve the se...

Integrated optical biosensors are gaining increasing attention for their exploitation in lab-on-chip platforms. The standard detection method is based on the measurement of the shift of some optical quantity induced by the immobilization of target molecules at the surface of an integrated optical element upon biomolecular recognition. However, this...

The use of micro- and nanoparticles in biological applications has dramatically grown during the last few decades due to the ease of protocols development and compatibility with microfluidics devices. Particles can be composed by different materials, i.e., polymers, inorganic dielectrics, and metals. Among them, silica is a suitable material for th...

We developed a biosensing system for serological detection of viruses based on the impedance variation between gold microelectrodes upon the capture of the target antibodies hybridized with nanobeads for signal amplification. The microfluidic platform core features a Differential Impedance Sensing (DIS) architecture between a reference and an activ...

The analytical performance of the microarray technique in screening the affinity and reactivity of molecules towards a specific target, is highly affected by the coupling chemistry adopted to bind probes to the surface. However, the surface functionality limits the biomolecules that can be attached to the surface to a single type of molecule, thus...

The physical–chemical properties of the surface of DNA microarrays and biosensors play a fundamental role in their performance, affecting the signal’s amplitude and the strength and kinetics of binding. We studied how the interaction parameters vary for hybridization of complementary 23-mer DNA, when the probe strands are immobilized on different c...

The capillary zone electrophoresis (CZE) has recently been proposed by our group as a novel technique for outer membrane vesicles (OMVs) characterization (J. Chromatography 1621 (2020) 461047). In present work the impact of selected parameters of CZE method on OMVs isolates analysis was assessed. It was shown that the extension of sample injection...

A new coronavirus (SARS-CoV-2) caused the current coronavirus disease (Covid-19) epidemic. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) is used as the gold standard for clinical detection of SARS-CoV-2. Under ideal conditions, RT-qPCR Covid-19 assays have analytical sensitivity and specificity greater than 95%. However, wh...

Extracellular vesicles (EVs) have attracted considerable interest due to their role in cell-cell communication, disease diagnosis, and drug delivery. Despite their potential in the medical field, there is no consensus on the best method for separating micro- and nanovesicles from cell culture supernatant and complex biological fluids. Obtaining a g...

It is widely accepted that assessing circular tumor DNA (ctDNA) in the plasma of cancer patients is a promising practice to evaluate somatic mutations from solid tumors noninvasively. Recently, it was reported that isolation of extracellular vesicles improves the detection of mutant DNA from plasma in metastatic patients; however, no consensus on t...

Background: A new coronavirus (SARS-CoV-2) caused the current Covid-19 epidemic. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) is used as the gold standard for clinical detection of SARS-CoV-2. Under ideal conditions RT-qPCR Covid-19 assays have analytical sensitivity and specificity greater than 95%. However, when the samp...

The manufacture of a very high-quality microarray support is essential for the adoption of this assay format in clinical routine. In fact, poorly surface-bound probes can affect the diagnostic sensitivity or, in worst cases, lead to false negative results. Here we report on a reliable and easy quality control method for the evaluation of spotted pr...

The analytical performance of the microarray technique in screening the affinity and reactivity of several probes towards a specific target, is highly affected by the coupling chemistry adopted to bind probes to the surface. However, the surface functionality limits the biomolecules that can be attached to the surface to a single type of molecule (...

Microarrays were introduced to run multiple assays on a single platform. Since then, researchers developed DNA and protein microarrays to study both transcription and expression of genes. Protein microarray technology represents a powerful tool to get an insight into living systems. However, despite their enormous potential, the fabrication of prot...

Nanopore‐based resistive‐pulse recordings represent a promising approach for single‐molecule biophysics with applications ranging from rapid DNA and RNA sequencing to “fingerprinting” proteins. Based on advances in fabrication methods, solid‐state nanopores are increasingly providing an alternative to proteinaceous nanopores from living organisms;...

Extracellular vesicles (EVs) have attracted great interest among researchers due to their role in cell-cell communication, disease diagnosis, and drug delivery. In spite of their potential in the medical field, there is no consensus on the best method for separating microvesicles from cell culture supernatant and complex biological fluids. Obtainin...

An optimized general protocol for DNA-protein ligation is provided and the conjugates are used to convert DNA arrays into antibody microarrays. Arrays obtained through DDI were used to capture and characterize extracellular vesicles (EVs), an emerging class of biomarkers. The proposed platform was tested against commercially available antibody micr...

The extracellular vesicles (EVs) released by plant pathogens of the Pectobacterium genus were investigated. The isolates were obtained using differential centrifugation followed by filtration and were characterized in terms of total protein content and particle size distribution. The transmission electron microscopy (TEM) analysis revealed the pres...

Bioprobes immobilization methods that elevate the probes from the substrate are generally preferred in microarray technology because they prevent steric limitations during the hybridization of the target to probes. A versatile approach to control the thickness of a polymeric coating based on click chemistry to obtain covalently linked layer-by-laye...

Surface chemistry is a crucial aspect for microarray modality biosensor development. The immobilization capability of the functionalized surface is indeed a limiting factor for the final yield of the binding reaction. In this work, we were able to simultaneously compare the functionality of protein ligands that were locally immobilized on different...

p>Surface chemistry is one of the most crucial aspects for microarray modality biosensor development. As a matter of fact, the immobilization capability of the functionalized surface is one of the limiting factors for the final yield of the binding reaction. In this work, we locally deposited many reactive polymers on a single solid support, allowi...

The use of peptides in paper-based analytics is a highly appealing field, yet it suffers from severe limitations. This is mostly due to the loss of effective target recognition properties of this relatively small probes upon nonspecific adsorption onto cellulose substrates. Here we address this issue by introducing a simple polymer-based strategy t...

The use of peptides in paper-based analytics is a highly appealing field, yet it suffers from severe limitations. This is mostly due to the loss of effective target recognition properties of this relatively small bioprobes upon nonspecific adsorption onto cellulose substrates. Here, we address this issue by introducing a simple polymer-based strate...

The performance of microarray assays results from the optimization of several parameters: in particular, the physical-chemical properties of the surface play a pivotal role in determining the robustness of the technology. Usually, microarray substrates are entirely modified with coatings able to bind, covalently or not, bioprobes. Here we present a...

Antigen immunoreactivity is often determined by surface regions defined by the 3D juxtapositions of amino acids stretches that are not continuous in the linear sequence. As such, mimicking an antigen immunoreactivity by means of putative linear peptide epitopes for diagnostic purposes is not trivial. Here we present a straightforward and robust met...

The interaction of carbohydrates with a variety of biological targets, including antibodies, proteins, viruses, and cells are of utmost importance in many aspects of biology. Glycan microarrays are increasingly used to determine the binding specificity of glycan-binding proteins. In this study, a novel microarray support is reported for the fabrica...

In this study we demonstrate the potential of sequential injection of samples in capillary electrophoresis-mass spectrometry (CE-MS) for rapid and sensitive proteome characterization of human lymphoblastic T-cells (line CCRF-CEM). Proteins were extracted, enzymatically digested, and the resulting peptides fractionated by RP-HPLC. Twenty fractions w...

Background: Identifying physiologically relevant binding partners of amyloid-β (Aβ) that modulate in vivo fibril formation may yield new insights into Alzheimer's disease (AD) etiology. Human cathelicidin peptide, LL-37, is an innate immune effector and modulator, ubiquitous in human tissues and expressed in myriad cell types. Objective: We pres...

We are investigating the molecular biophysics of the early-stage etiology of sporadic Alzheimer’s Disease (AD). What might cause initial accumulation of Aβ peptide-rich fibrils and plaques in the AD brain? What is Aβ’s physiological function? We focus on Aβ’s interactions with the human cathelicidin peptide, LL-37, an antibacterial and antiviral in...

This work introduces a novel sieving gel for DNA electrophoresis using a classical click chemistry reaction, the copper (I)-catalyzed azide-alkyne cycloaddition (CuAAC), to cross-link functional polymer chains. The efficiency of this reaction provides, under mild conditions, hydrogels with near-ideal network connectivity and improved physical prope...

Multiple ligand presentation is a powerful strategy to enhance the affinity of a probe for its corresponding target. A promising application of this concept lies in the analytical field, where surface immobilized probes interact with their corresponding targets in the context of complex biological samples. Here we investigate the effect of multiple...

The generation of robust analytical data using microarray platforms strictly relies on optimal ligand-target interaction at the sensor surface which, in turn, is inherently bound to the correct immobilization scheme of the interrogated bioprobes. In the present work, we performed a rigorous comparative analysis of the impact of peptide ligands immo...

In this work we report on the post-polymerization modification (PPM) of a polymer to introduce new functionalities that enable click chemistry reactions, for microarray applications. The parent polymer, named Copoly(DMA-NAS-MAPS), is composed of N,N-dimethylacrylamide (DMA), a monomer that self adsorbs onto different materials through weak interact...

Efficient diagnosis of emerging and novel bacterial infections is fundamental to guide decisions on therapeutic treatments. Here, we engineered a novel rational strategy to design peptide microarray platforms, which combines structural and genomic analyses to predict the binding interfaces between diverse protein antigens and antibodies against Bur...

Capillary electrophoresis (CE) is one of the most powerful techniques for the separation of biomolecules. However, the separation efficiency of proteins in CE is often compromised by their tendency to interact with the silanol groups on the surface of the inner capillary and by an uncontrolled electroosmotic flow. Herein, we report on the use of no...

We have investigated the behavior of thiol-ene substrates that is a class of promising materials for lab-on-a-chip electrophoresis applications. Two polymeric materials were prepared by copolymerization of N,N-dimethylacrylamide (DMA), (3-(methacryloyl-oxy)propyl)trimethoxysilane (PMA) and 3-trimethylsilanyl-prop-2-yne methacrylate (MAPS) and speci...

The goal of this work is to develop an innovative approach for the coating of gold nanoparticles (AuNPs) with a synthetic functional copolymer. This stable coating with a thickness of few nanometers provides stabilization and functionalization of the particles at the same time. The polymeric coating consists of a backbone of polydimethylacrylamide...

The fabrication of high density microarrays requires a precise control of surface physical and chemical properties. In fact, spot morphology has a deep impact on signal level and might affect seriously the reliability and reproducibility of the assay. As a consequence, a proper biomolecule deposition and immobilization increases the accuracy of dat...

A new methodology for the fabrication of an high-performance peptide microarray is reported, combining the higher sensitivity of a layered Si–SiO2substrate with the oriented immobilization of peptides using a N,N- dimethylacrylamide-based polymeric coating that contains alkyne monomers as functional groups. This clickable polymer allows the oriente...

We analyze the electroosmotic flow (EOF) of an electrolytic solution in a polymer coated capillary electrophoresis tube. The polymeric density, charge, thickness, and the capillary tube charge vary as a function of pH and produce a non-trivial modulation of the EOF, including a flow reversal at acid pH conditions. By means of a theoretical argument...

Separation of proteins in capillary electrophoresis (CE) is often hindered by their interactions with the silanols groups on the inner surface of the fused silica capillary. In particular, the positive charges of alkaline proteins establish electrostatic interactions with the negative charges of the surface, leading to peak broadening and loss of s...

Single-molecule detection and counting is the new frontier in biomarker analysis. Here, we report on recent techniques for the digital detection of biomolecules for clinical application. First we highlight methods based on the immunocapture of proteins onto microparticles, followed by isolation of individual particles in microenvironments so that a...

Nano fluidic sensing devices promise high performance by overcoming issues of mass transport of analyte molecules to the sensing surface, whilst micro-porous membranes promise high sensitivity due to a large surface for their capture. Anodic alumina (AAO) filter membranes allow the flow through of samples, and could be used as a convenient and read...

Despite the continuous advancements in bio-molecular detection methods and fluidic integration approaches, the realization of portable and high performance devices for diagnostic applications still presents major difficulties, mostly due to the need of combining adequate sensitivity with low cost of production, operational simplicity and rapidity....

To date, photonic biosensing with porous membranes has produced slow responses and long sensing times, due to the narrow (less than 100 nm) closed end pores of the membranes used. Recently, polarimetry was used to demonstrate analyte flow through, and real time biosensing in, free-standing porous alumina membranes. Here, we demonstrate how an impro...

The analysis of high molecular weight (HMW) proteins from complex mixtures is still a challenge in proteomics. This work introduces a novel hydrogel obtained by the copolymerization of an allyl polyvinyl alcohol derivative (allyl-PVA) with acrylamide and BISacrylamide and applies this matrix to the electrophoretic separation of HMW proteins. By ind...

The quality of separation in capillaries electrophoresis is strongly affected by the magnitude of the electroosmotic flow (EOF). The EOF can be efficiently suppressed by coating the capillary wall with hydrophilic polymers. In this paper, experimental data are presented to show the effect of coating thickness and charge on mass transport. Simulatio...

In this work, a new method to functionalize a gold surface by dip coating with a functional copolymer is presented. The coating procedure is simple, robust and can be accomplished in less than one hour. Atomic force microscopy (AFM) scratch tests reveal the presence of a homogeneous polymer coating with a thickness of 2.5 nm. X-ray photoemission sp...

We report on the fabrication of a microfluidic cell completely made of thiol-ene for microarray applications. To overcome the issues related to the hydrophobic nature of the thiol-ene material we have also introduced a new polymeric coating based of N, N-dimethylacrylamide (DMA) which is able to reduce the material hydrophobicity, to avoid aspecifi...

We present a facile, one-pot procedure for the organic-to-water phase transfer and biofunctionalization of semiconductor nanocrystals (quantum dots, or QDs) which employs a synthetic functional copolymer, namely poly(DMA-NAS-MAPS), consisting of three components: a surface interacting monomer, N,N-dimethylacrylamide (DMA), a chemically reactive mon...

This review focuses on the fluorescent protein microarrays applied to neurodegenerative disorders, a major health problem in our aging society. Biomarker discovery studies and work on new diagnostic tests are both included. Three platforms are described: antibody planar microarrays, comprising an array of well-defined antibodies for the simultaneou...

A number of materials used to fabricate disposable microfluidic devices are hydrophobic in nature with water contact angles on their surface ranging from 80° to over 100°. This characteristic makes them unsuitable for a number of microfluidic applications. Both the wettability and analyte adsorption parameters are highly dependent on the surface hy...

Polymeric coatings, usually referred as tridimensional chemistries, provide homogenous surface derivatization methods presenting a high reactive group concentration and resulting in an increased binding capacity of targets. Furthermore, they act as linkers distributing the bound probe also in the axial position, thus causing a faster reaction with...

In this work, calculations and preliminary experimental data for determining the optimal condition for the selective bio-functionalization of magnetic tunneling junction (MTJ)-based biosensors are presented. Results on the detection of biomolecular recognition events employing MTJ-based sensor and magnetic beads are presented and interpreted throug...

Recognizing and quantifying specific biomolecules in aqueous samples are constantly needed in research and diagnostic laboratories. As the typical detection procedures are rather lengthy and involve the use of labeled secondary antibodies or other agents to provide a signal, efforts have been made over the last 10 y to develop alternative label-fre...

We report the first demonstration of real-time biosensing in free standing macroporous alumina membranes. The membranes with their 200 nm diameter pores are ideal candidates for biosensing applications where fast response times for small sample volumes are needed as they allow analytes to flow through the pores close to the bioreceptors immobilized...

In this work, we present a highly sensitive immunoassay for the detection of the Alzheimer's disease (AD) biomarker amyloid-beta 1-42 (Aβ42) based on a label/label-free microarray platform that utilises silicon/silicon oxide (Si/SiO2) substrates. Due to constructive interference, Si/SiO2 layered slides allow enhancement of the fluorescence intensit...

The accuracy of antibody-based microarrays depends on eliminating or at least minimizing the effect of cross-reactive components. In this work, a method to create a versatile, compartmentalized storage system for antibodies and soluble microarray reagents is described. These containers are made of hydrogel plugs immobilized on a slide facing the co...

In this work, we present a highly sensitive immunoassay for the detection of the Alzheimer's disease (AD) biomarker amyloid-beta 1-42 (Aβ42) based on a label/label-free microarray platform that utilises silicon/silicon oxide (Si/SiO2) substrates. Due to constructive interference, Si/SiO 2 layered slides allow enhancement of the fluorescence intensi...

We demonstrate the application of a novel smart surface to modulate the orientation of immobilized double stranded DNA (dsDNA) and the conformation of a polymer scaffold through variation in buffer pH and ionic strength. An amphoteric poly(dimethylacrylamide) based coating containing weak acrylamido acids and bases, which are copolymerized together...

Capillary electrophoresis (CE) is one of the most powerful techniques for the separation of biomolecules. However, the separation efficiency of proteins in CE is often compromised by their tendency to interact with the silanol groups on the surface of the inner capillary and by an uncontrolled electroosmotic flow. Herein, we report on the synthesis...

Protein and DNA microarrays hold the promise to revolutionize the field of molecular diagnostics. Traditional microarray applications employ labeled detection strategies based on the use of fluorescent and chemiluminescent secondary antibodies. However, the development of high throughput, sensitive, label-free detection techniques is attracting att...

We utilize spectral self-interference fluorescent microscopy (SSFM) to measure fluorophore height with sub-nm precision to precisely quantify DNA orientation and conformation. A novel polymeric 3D scaffold is used to functionalize the sensor surface and permits controlled orientation of the surface anchored DNA.