Detection of Listeria monocytogenes in foods with a textile organic electrochemical transistor biosensor.

Foods contaminated by pathogens are responsible for foodborne diseases which have socioeconomic impacts. Many approaches have been extensively investigated to obtain specific and sensitive methods to detect pathogens in food, but they are often not easy to perform and require trained personnel. This work aims to propose a textile organic electrochemical transistor-based (OECT) biosensor to detect L.

Long-Term Stability in Electronic Properties of Textile Organic Electrochemical Transistors for Integrated Applications.

Organic electrochemical transistors (OECTs) have demonstrated themselves to be an efficient interface between living environments and electronic devices in bioelectronic applications. The peculiar properties of conductive polymers allow new performances that overcome the limits of conventional inorganic biosensors, exploiting the high biocompatibility coupled to the ionic interaction. Moreover, the combination with biocompatible and flexible substrates, such as textile fibers, improves the interaction with living cells and allows specific new applications in the biological environment, including real-time analysis of plants' sap or human sweat monitoring.

Methylglyoxal Adducts Levels in Blood Measured on by Portable Near-Infrared Spectroscopy.

The altered glucose metabolism characterising cancer cells determines an increased amount of methylglyoxal in their secretome. Previous studies have demonstrated that the methylglyoxal, in turn, modifies the protonation state (PS) of soluble proteins contained in the secretomes of cultivated circulating tumour cells (CTCs). In this study, we describe a method to assess the content of methylglyoxal adducts (MAs) in the secretome by near-infrared (NIR) portable handheld spectroscopy and the extreme learning machine (ELM) algorithm.

Real-time monitoring of Arundo donax response to saline stress through the application of in vivo sensing technology.

One of the main impacts of climate change on agriculture production is the dramatic increase of saline (Na) content in substrate, that will impair crop performance and productivity. Here we demonstrate how the application of smart technologies such as an in vivo sensor, termed bioristor, allows to continuously monitor in real-time the dynamic changes of ion concentration in the sap of Arundo donax L. (common name giant reed or giant cane), when exposed to a progressive salinity stress.

Phenotyping for the Early Detection of Drought Stress in Tomato.

Drought stress imposes a major constraint over a crop yield and can be expected to grow in importance if the climate change predicted comes about. Improved methods are needed to facilitate crop management via the prompt detection of the onset of stress. Here, we report the use of an in vivo OECT (organic electrochemical transistor) sensor, termed as bioristor, in the context of the drought response of the tomato plant.

Tailoring Chemometric Models on Blood-Derived Cultures Secretome to Assess Personalized Cancer Risk Score.

The molecular protonation profiles obtained by means of an organic electrochemical transistor, which is used for analysis of molecular products released by blood-derived cultures, contain a large amount of information The transistor is based on the conductive polymer PEDOT:PSS comprising super hydrophobic SU8 pillars positioned on the substrate to form a non-periodic square lattice to measure the state of protonation on secretomes derived from liquid biopsies. In the extracellular space of cultured cells, the number of glycation products increase, driven both by a glycolysis metabolism and by a compromised function of the glutathione redox system. Glycation products are a consequence of the interaction of the reactive aldehydes and side glycolytic products with other molecules.

Emerging Designs of Electronic Devices in Biomedicine.

A long-standing goal of nanoelectronics is the development of integrated systems to be used in medicine as sensor, therapeutic, or theranostic devices. In this review, we examine the phenomena of transport and the interaction between electro-active charges and the material at the nanoscale. We then demonstrate how these mechanisms can be exploited to design and fabricate devices for applications in biomedicine and bioengineering.

Development of an In Vivo Sensor to Monitor the Effects of Vapour Pressure Deficit (VPD) Changes to Improve Water Productivity in Agriculture.

Environment, biodiversity and ecosystem services are essential to ensure food security and nutrition. Managing natural resources and mainstreaming biodiversity across agriculture sectors are keys towards a sustainable agriculture focused on resource efficiency. Vapour Pressure Deficit (VPD) is considered the main driving force of water movements in the plant vascular system, however the tools available to monitor this parameter are usually based on environmental monitoring.

An in vivo biosensing, biomimetic electrochemical transistor with applications in plant science and precision farming.

The in vivo monitoring of key plant physiology parameters will be a key enabler of precision farming. Here, a biomimetic textile-based biosensor, which can be inserted directly into plant tissue is presented: the device is able to monitor, in vivo and in real time, variations in the solute content of the plant sap. The biosensor has no detectable effect on the plant's morphology even after six weeks of continuous operation.

Geometrical Patterning of Super-Hydrophobic Biosensing Transistors Enables Space and Time Resolved Analysis of Biological Mixtures.

Pedot: PSS is a conductive polymer that can be integrated into last generation Organic Electrochemical Transistor (OECT) devices for biological inspection, identification and analysis. While a variety of reports in literature demonstrated the chemical and biological sensitivity of these devices, still their ability in resolving complex mixtures remains controversial. Similar OECT devices display good time dynamics behavior but lack spatial resolution.

Titanyl phthalocyanine ambipolar thin film transistors making use of carbon nanotube electrodes.

The capability of efficiently injecting charge carriers into organic films and finely tuning their morphology and structure is crucial to improve the performance of organic thin film transistors (OTFTs). In this work, we investigate OTFTs employing carbon nanotubes (CNTs) as the source-drain electrodes and, as the organic semiconductor, thin films of titanyl phthalocyanine (TiOPc) grown by supersonic molecular beam deposition (SuMBD). While CNT electrodes have shown an unprecedented ability to improve charge injection in OTFTs, SuMBD is an effective technique to tune film morphology and structure.

Human stress monitoring through an organic cotton-fiber biosensor.

Selective detection of bioanalytes in physiological fluids, such as blood, sweat or saliva, by means of low-cost and non-invasive devices, is of crucial importance to improve diagnosis and prevention in healthcare. To be really useful in everyday life a sensing system needs to be handy, non-invasive, easy to read and possibly wearable. Only a sensor that satisfies these requirements could be eligible for applications in healthcare and physiological condition monitoring.

Diffusion driven selectivity in organic electrochemical transistors.

Organic Electrochemical transistors (OECTs) present unique features for their strategic combination with biomedical interfaces, simple and low voltage operation regime and sensing ability in aqueous environment, but they still lack selectivity, so that a significant effort in research is devoted to overcome this limitation. Here, we focus on the diffusion properties of molecular species in the electrolyte, which opportunely analyzed, modeled and compared to experimental data, serve as a simple and direct key factor in the recognition of species during OECT sensing. Specifically, we model the transient behavior of an OECT considering the effect of diffusion of the target species in the electrolyte.

Microtexturing of the conductive PEDOT:PSS polymer for superhydrophobic organic electrochemical transistors.

Superhydrophobic surfaces are bioinspired, nanotechnology artifacts, which feature a reduced friction coefficient, whereby they can be used for a number of very practical applications including, on the medical side, the manipulation of biological solutions. In this work, we integrated superhydrophobic patterns with the conducting polymer PEDOT:PSS, one of the most used polymers in organic electronics because highly sensitive to ionized species in solution. In doing so, we combined geometry and materials science to obtain an advanced device where, on account of the superhydrophobicity of the system, the solutions of interest can be manipulated and, on account of the conductive PEDOT:PSS polymer, the charged molecules dispersed inside can be quantitatively measured.

Irreversible evolution of eumelanin redox states detected by an organic electrochemical transistor: en route to bioelectronics and biosensing.

Organic electrochemical transistors (OECTs) are currently emerging as powerful tools for biosensing, bioelectronics and nanomedical applications owing to their ability to operate under liquid phase conditions optimally integrating electronic and biological systems. Herein we disclose the unique potential of OECTs for detecting and investigating the electrical properties of insoluble eumelanin biopolymers. Gate current measurements on fine aqueous suspensions of a synthetic eumelanin sample from 5,6-dihydroxyindole (DHI) revealed a well detectable hysteretic response similar to that of the pure monomer in solution, with the formal concentration of the polymer as low as 10 M.

Low temperature sensing properties of a nano hybrid material based on ZnO nanotetrapods and titanyl phthalocyanine.

ZnO nanotetrapods have recently been exploited for the realization of high-sensitivity gas sensors, but they are affected by the typical drawbacks of metal-oxides, i.e., poor selectivity and a relatively high working temperature.

Liposome sensing and monitoring by organic electrochemical transistors integrated in microfluidics.

Background: Organic electrochemical transistors (OECTs), which are becoming more and more promising devices for applications in bioelectronics and nanomedicine, are proposed here as ideally suitable for sensing and real time monitoring of liposome-based structures. This is quite relevant since, currently, the techniques used to investigate liposomal structures, their stability in different environments as well as drug loading and delivery mechanisms, operate basically off-line and/or with pre-prepared sampling.

Methods: OECTs, based on the PEDOT:PSS conductive polymer, have been employed as sensors of liposome-based nanoparticles in electrolyte solutions to assess sensitivity and monitoring capabilities based on ion-to-electron amplified transduction.

Superhydrophobic surfaces as smart platforms for the analysis of diluted biological solutions.

The aim of this paper is to expound on the rational design, fabrication and development of superhydrophobic surfaces (SHSs) for the manipulation and analysis of diluted biological solutions. SHSs typically feature a periodic array or pattern of micropillars; here, those pillars were modified to incorporate on the head, at the smallest scales, silver nanoparticles aggregates. These metal nanoclusters guarantee superior optical properties and especially SERS (surface enhanced Raman scattering) effects, whereby a molecule, adsorbed on the surface, would reveal an increased spectroscopy signal.

Polymorphism and phase control in titanyl phthalocyanine thin films grown by supersonic molecular beam deposition.

Polymorphism in the growth of titanyl phthalocyanine films on dielectric substrates has been systematically studied by UV absorption and micro-Raman analyses, correlating structure and optical properties. We explored different growth regimes as a function of substrate temperature and growth rate using hyperthermal seeded supersonic beams. We identify and discuss specific signatures in micro-Raman spectra specifically correlated to the different phases and demonstrate the unprecedented ability of growing crystalline films and controlling the relative abundance of the different phases (amorphous, phase I, and phase II) by the beam parameters.