Waldemar Alejandro Marmisollé

• Dr
• Researcher at National Scientific and Technical Research Council

We developed an arginine-responsive biosensor by integrating cascade enzymatic reactions into nanochannels functionalized with weak polyelectrolytes, which serve as "reactive signal amplifiers." This approach enhances device performance and broadens the...

Herein, we present a novel approach to quantify ferritin based on the integration of an Enzyme-Linked Immunosorbent Assay (ELISA) protocol on a Graphene Field-Effect Transistor (gFET) for bioelectronic immunosensing. The G-ELISA strategy takes advantage of the gFET inherent capability of detecting pH changes for the amplification of ferritin detect...

Chronic kidney disease (CKD) is a significant global health concern, impacting over 10% of the world population. Despite advances in home‐based treatments, CKD diagnosis and monitoring remain centralized in large laboratories. This work reports on the development of a Graphene‐based Lab‐On‐a‐Chip (G‐LOC) for the self‐testing of multiple renal funct...

We present the construction of an organic electrochemical transistor (OECT) based on poly(3,4-ethylendioxythiophene, PEDOT) and polyallylamine (PAH) and its evaluation as a bioelectronic platform for urease integration and urea sensing. The OECT channel was fabricated in a one-step procedure using chemical polymerization. Then, urease was immobiliz...

Solid-state nanochannels (SSNs) have emerged as promising platforms for controlling ionic transport at the nanoscale. SSNs are highly versatile, and this feature can be enhanced through their combination with porous materials such as Metal−Organic Frameworks (MOF). By selection of specific building blocks and experimental conditions, different MOF...

In this study, the transport of salt with moderate solubility through bioinspired solid-state nanochannels was comprehensively investigated. For this purpose, bullet-shaped channels were fabricated and exposed to KClO4, a monovalent...

Chronic kidney disease is one of the major health issues worldwide. However, diagnosis is now highly centralized in large laboratories, resulting in low access to patient monitoring and poor personalized treatments. This work reports the development of a graphene-based lab-on-a-chip (G-LOC) for the digital testing of renal function biomarkers in se...

Nanofluidic field-effect transistors for tailored transport and bio-inspired functionalities: solid-state nanochannels can be smartly tuned by external potentials to induce open/closed states or promote ion selectivity in the same way as biological ion channels.

Supercapacitors are devices that bridge the gap between traditional capacitors and rechargeable batteries, offering exceptional energy storage capabilities, rapid charge/discharge rates, long cycle life, and environmental friendliness. This study explores the development of neutral-aqueous supercapacitor materials using conductive polymers, with a...

We studied ionic transport properties of UiO-66 metal-organic framework-modified solid-state nanochannels (MOF@SSNs) embedded in polyethylene terephthalate (PET) membranes, focusing on the effect of calcium ions from chloride salt (CaCl2) acting...

Neurotransmitters are endogenous chemical messengers that play crucial roles in the transmission, enhancement and conversion of specific signals between neurons and other cells and are considered biomarkers of neurodegenerative diseases.[1] Neurodegenerative diseases cause progressive loss of cognitive and/or motor function and, as life expectancy...

In this chapter, we will give a briefing about the factors that influence a TC of macromolecular substances.

One of the main applications of binding is titrations. It has been written a lot about the subject (See for instance, [1,2]).

In this chapter we will consider examples of the titration of polyacids and polybases. These may be polymers in solution or substances in different states as colloids, solid films on top of electrodes, or other natural and synthetic macromolecules.

In the previous chapter we analysed the case colloidal oxides that can be considered as substances that have the particularity that the binding sites may behave as both acid and basic sites at the same time, that is, being polyampholytes.

In previous chapters we have defined ampholytes as those substances that have acid and basic groups in the same molecule. Polyampholytes may be defined as those that have many acid and basic groups in the macromolecule. There may be synthetic and natural polyelectrolytes.

We start with this kind of processes as they are more familiar to science students.

In this chapter we will consider one substrate with two different binding sites, different binding species on the same substrate and two different binding species on different sites of a given substrate.

Electroactive macromolecular substances have widely attracted the scientific attention because of their crucial role in natural processes and technological importance.

Polyacids and polybases are a particular kind of macromolecules.

We have referred before to the fact that two sites may or may not have different binding constants (it is also said they have different affinities).

In the forthcoming chapters we will see that the binding energy, and consequently the binding constant, depends on the extension of the binding.

In order to interpret the TCs in complex systems, it is necessary to work out first a number of matters. Among them there is the question of the different types of binding. Considering the type of bonding between the adsorbate and the atoms of the substrate we may differentiate those in which the forces involved in bonding are of the van der Waals...

Organic electrochemical transistors (OECTs) are important devices for the development of flexible and wearable sensors due to their flexibility, low power consumption, sensitivity, selectivity, ease of fabrication, and compatibility with other flexible materials. These features enable the creation of comfortable, versatile, and efficient portable d...

The layer-by-layer (LbL) technique has been proven to be one of the most versatile approaches in order to fabricate functional nanofilms. The use of simple and inexpensive procedures as well as the possibility to incorporate a very wide range of materials through different interactions have driven its application in a wide range of fields. On the o...

The complexation of polyelectrolytes with other oppositely charged structures gives rise to a great variety of functional materials with potential applications in a wide spectrum of technological fields. Depending on the assembly conditions, polyelectrolyte complexes can acquire different macroscopic configurations such as dense precipitates, nanos...

The fabrication of efficient organic electrochemical transistors (OECTs)-based biosensors requires the design of biocompatible interfaces for the immobilization of biorecognition elements, as well as the development of robust channel materials to enable the transduction of the biochemical event into a reliable electrical signal. In this work, PEDOT...

"Clickable" organic electrochemical transistors (OECTs) allow the reliable and straightforward functionalization of electronic devices through the well-known click chemistry toolbox. In this work, we study various aspects of the click chemistry-based interface engineering of "clickable" OECTs. First, different channel architectures are investigated...

[This corrects the article DOI: 10.1021/jacsau.2c00515.].

Nanofluidic channels in which the ionic transport can be modulated by the application of an external voltage to the nanochannel walls have been described as nanofluidic field effect transistors (nFETs) because of their analogy with electrolyte-gated field effect transistors. The creation of nFETs is attracting increasing attention due to the possib...

Recent developments surrounding the oxygen reduction reaction (ORR) focus on low‐cost alternatives to materials used in traditional electrodes, e. g. Pt. To accumulate competitive advantages, these non‐traditional electrodes often consist of multiple functional coating layers. Considering that each layer can potentially alter the reaction mechanism...

Interfacing the surface of an organic semiconductor with biological elements is a central quest when it comes to the development of efficient organic bioelectronic devices. Here, we present the first example of “clickable” organic electrochemical transistors (OECTs). The synthesis and characterization of an azide-derivatized EDOT monomer (azidometh...

The use of track-etched membranes allows further fine-tuning of transport regimes and thus enables their use in (bio)sensing and energy harvesting applications, among others. Recently, metal-organic frameworks (MOFs) have been combined with such membranes to further increase their potential. Herein, the creation of a single track-etched nanochannel...

The interaction between polyamines and phosphate species is found in a wide range of biological and abiotic systems, yielding crucial consequences that range from the formation of supramolecular colloids to structure determination. In this work, the occurrence of phosphate-amino interactions is evidenced from changes in the electronic response of g...

Acetylcholinesterase-modified nanochannels are proposed as reliable and reproducible nanofluidic sensors for highly sensitive detection of acetylcholine. The operation mechanism relies on the use of weak polyelectrolytes as "chemical amplifiers" that adjust/reconfigure the nanochannel surface charge in the presence of local pH changes induced by th...

Graphene field-effect transistors (gFETs) are promising tools for the development of precise and affordable techniques for the study of molecular binding kinetics, crucial in applications such as biomolecule therapies, drug discovery, and medical diagnostics. Nevertheless, determining the reliability and modeling the gFET signal for the monitoring...

Conjugated polymers (CP) constitute nonexpensive stable building blocks for the construction of a variety of electrochemically active complex materials. Due to their particular electronic structure, they present as light metal-free conducting materials that can be prepared using soft chemical methods. This makes them immensely suitable for electroc...

The biofunctionalization of graphene field-effect transistors (GFETs) through vinylsulfonated-polyethyleneimine nanoscaffold is presented for enhanced biosensing of severe acute respiratory-related coronavirus 2 (SARS-CoV-2) spike protein and human ferritin, two targets of great importance for the rapid diagnostic and monitoring of individuals with...

The concept of nanoarchitechtonics was introduced to describe the correct manipulation of nanoscale materials in the creation of nano-devices and applications. Nanoarchitectonics has begun to spread into many fields including nanostructured materials synthesis, supramolecular assembly, nanoscale structural fabrications, materials hybridizations, ma...

During the past decade, solid-state nanopores and nanochannels (SSNs) have emerged as a new class of devices for the creation of nanofluidic platforms with diverse applications. In particular, the precise control of ion transport achieved by SSNs paved the way to the development of specific and efficient biological and chemical iontronic sensors wi...

It is well known that graphene field-effect transistors (gFETs) are sensitive to changes in the pH of the solution in which they are immersed, and this phenomenon allows the (bio)sensing of different analytes. 1,2 In this work, we study a possible treatment to increase the pH sensitivity of gFETs. Under the hypothesis that gFETs with a greater oxid...

We introduce a new approach for glucose oxidase (GOx) immobilization on graphene field-effect transistors (gFETs) to fabricate highly sensitive glucose sensors. The strategy relies on the electropolymerization of a layer of the copolymer polyIJ3-amino-benzylamine-co-aniline) (PABA) on graphene-based transistors. The synthesized polymer film provides...

We present a strategy for the integration of three building blocks in a functional interfacial nanoarchitecture in order to fabricate composite films with improved features towards the electrochemical oxygen reduction reaction (ORR). Firstly, multilayer films of polyethyleneimine (PEI) and poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (...

Advanced nanostructured membranes with high ion flux and selectivity bring new opportunities for generating clean energy by exploiting the osmotic pressure difference between water sources of different salinities.

Biomimetic solid-state nanochannels enable new modalities for biosensing. In the last decade, these nanofluidic architectures have been widely studied due to their rapid and sensitive detection capabilities. Developing nanofluidic sensors with great ability to sense ions, small biomolecules, and biological macromolecules requires the combination of...

Organic bioelectronics involves the connection of organic semiconductors with living organisms, organs, tissues, cells, membranes, proteins, and even small molecules. In recent years, this field has received great interest due to the development of all kinds of devices architectures, enabling the detection of several relevant biomarkers, the stimul...

Recently, much scientific effort has been centered on the control of the ionic transport properties of solid state nanochannels and the rational design and integration of chemical systems to induce changes in the ionic transport by means of interactions with selected target molecules. Here, we report the fabrication of a novel nanofluidic device ba...

The construction of organic electrochemical transistors (OECTs) using poly(3,4‐ethylenedioxythiophene):tosylate and polyallylamine hydrochloride composites as conducting channel material is presented. The regulation of the polyelectrolyte‐to‐conducting polymer proportion allows one to easily tune both electronic and ionic characteristics of the tra...

During the last years, much scientific effort has been focused on the control of the ionic transport properties of solid state nanochannels and the rational integration of chemical systems to induce changes in the ionic transport by interaction with selected target molecules for (bio)sensing purposes. In this work, we present the construction and f...

Solid-state nanochannels have attracted substantial attention of the scientific community due to the remarkable control of ionic transport and the feasibility to regulate the iontronic output by different stimuli. Most of the developed nanodevices are subjected to complex modification methods or show functional responsiveness only in moderate ionic...

Carbon nanomaterials are usually employed for improving the electrical and electrochemical properties of conducting polymer electrodes. However, low-cost of production, scalable simple procedures and adequate integration of the components at the molecular level within the composites become a challenge when dealing with real life applications. In th...

Polyamine-salt aggregates have become promising soft materials in nanotechnology due to their easy preparation process and pH-responsiveness. Here, we report the use of hexacyanoferrate (II) and hexacyanoferrate (III) as electroactive crosslinking agents for the formation of nanometer-sized redox-active polyamine-redox-salt aggregates (rPSA) in bul...

Nanofluidic field-effect transistors (nFETs) have attracted the attention of scientific community due to its remarkable level of control over ionic transport. Particularly, the combination of nanofluidic systems and electroactive polymers has demonstrated being an interesting approach to achieve an electrochemically addressable device. In this work...

Polyamine–salt aggregates (PSA) are biomimetic soft materials that have attracted great attention due to their straightforward fabrication methods, high drug‐loading efficiencies, and attractive properties for pH‐triggered release. Herein, a simple and fast multicomponent self‐assembly process was used to construct cross‐linked poly(allylamine hydr...

Nanofluidic reverse electrodialysis systems based on track-etched nanochannels are promising devices for new eco-friendly ways of sustainable energy generation. In recent years, several works have been focused on the influence of parameters such as pH, ionic strength, and chemical nature of the electrolyte on the device performance. However, despit...

Multistage delivery systems with size reduction capacity have been proposed as a powerful strategy for improving tissue drug penetration. Here we developed a simple and fast supramolecular approach to construct size-shrinkable polyamine-salt aggregates by ionic cross-linking of biodegradable poly-L-lysine dendrigraft with tripolyphosphate anion. Th...

Responsive nanomaterials have emerged as key components in materials sciences. Herein, we report the one-step preparation of multi-stimuli responsive polyamine-salt aggregates (PSA) by ionically crosslinking polyethylenimine with potassium ferrioxalate (FeOx)....

In the last years the ionic conductance behavior of solid-state nanochannels (SSN) has been extensively studied with both basic and applied purposes. In particular, the interactions between confined groups and dissolved species have been widely used for the design of biosensors and smart devices. Being the species confined to the small volume of th...

In this work we explore a nanoarchitectonics approach to construct functional composite nanomaterials with enhanced electrocatalytic properties. Functional electrodes were designed in order to combine two key elements: high surface area and porosity with electroactivity, thus enabling their application to the enhancement of the electrochemical oxyg...

The ability to create extended porous networks, such as those composed of Metal Organic Frameworks (MOFs), with tailored hydrophilic/hydrophobic character is crucial for adapting such widely used supports to different applications. In order to achieve this goal, direct polymer inclusion has proven to be a suitable strategy, and functional composite...

Solid‐state nanopores are fascinating objects that enable the development of specific and efficient chemical and biological sensors, as well as the investigation of the physicochemical principles ruling the behavior of biological channels. The great variety of biological nanopores that nature provides regulates not only the most critical processes...

In the present work, we review the occurrence of capacitive currents in conducting polymer and, particularly, in the electrochemical response of polyaniline film-coated electrodes Firstly, we present and discuss the differences between the electrical double-layer capacitance and the so-called pseudocapacitance. Then, we discuss the capacitive behav...

The use of soft materials as building blocks in layer‐by‐layer (LbL) assemblies represent a very appealing and useful approach to enhance the loading capacity of thin films. Here, the capacity of positively charged polyamine‐salt aggregates (PSAs) based on ionically crosslinked poly(allylamine hydrochloride) (PAH) with phosphate anions (Pi) is expl...

Ionically crosslinked poly(allylamine)/phosphate (PAH/Pi) colloids consist of self‐assembled nanostructures stabilized by supramolecular interactions. Under physiological conditions, these interactions should be present at high ionic strength and only in a narrow pH window to be effective as drug delivery agents. In this work we study the effect of...

The discovery and development of novel approaches, materials and manufacturing processes in the field of energy are compelling increasing recognition as a major challenge for contemporary societies. The performance and lifetime of energy devices are critically dependent on nanoscale interfacial phenomena. From the viewpoint of materials design, the...

Supramolecular self-assembly of molecular building blocks represents a powerful "nanoarchitectonic" tool to create new functional materials with molecular-level feature control. Here, we propose a simple method to create tunable phosphate/polyamine-based films on surfaces by successive assembly of poly(allylamine hydrochloride) (PAH)/phosphate anio...

Since its discovery in the 80´s, Conducting Polymers have been extensively employed for the preparation of electrode materials in different applications from chemical and biochemical sensing to energy storage. Some of the comparative advantages of these materials are the facility of synthesis, low cost and low density. Particularly, their wide-spre...

Oxygen Reduction Reaction (ORR), essential in many energy conversion devices, takes particular relevance in facing the increasing global demand for clean energy sources and vectors. In this context, desirable features for ORR-based electrochemical cells are operability under environmentally-friendly conditions, such as pH 7 biocompatible electrolyt...

The modulation of cell adhesion via biologically inspired materials plays a key role in the development of realistic platforms to envisage not only mechanistic descriptions of many physiological and pathological processes but also new biointerfacial designs compatible with the requirements of biomedical devices. In this work, we show that the cell...

Supramolecular self-assembly is of paramount importance for the development of novel functional materials with molecular-level feature control. In particular, the interest in creating well-defined stratified multilayers through simple methods using readily available building blocks is motivated by a multitude of research activities in the field of...