Deciphering antioxidant interactions via data mining and RDKit.

Minimizing the oxidation of lipids remains one of the most important challenges to extend the shelf-life of food products and reduce food waste. While most consumer products contain antioxidants, the most efficient strategy is to incorporate combinations of two or more compounds, boosting the total antioxidant capacity. Unfortunately, the reasons for observing synergistic / antagonistic / additive effects in food samples are still unclear, and it is common to observe very different responses even for similar mixtures.

Combining digital imaging and quantum dots for analytical purposes.

This review provides a critical assessment of the most recent advances in digital imaging (DI) methods, applied for the development of analytical methodologies combining quantum dots (QDs). The state-of-the-art, treatment of data, instrumental considerations, software, sensing approaches, and optimization of the resulting methods are reported. Applications of the technology for the analysis of food and beverages, biomedically relevant analytes, drugs, environmental samples and forensic samples are also discussed.

Ultradense Array of On-Chip Sensors for High-Throughput Electrochemical Analyses.

High-throughput sensors are valuable tools for enabling massive, fast, and accurate diagnostics. To yield this type of electrochemical device in a simple and low-cost way, high-density arrays of vertical gold thin-film microelectrode-based sensors are demonstrated, leading to the rapid and serial interrogation of dozens of samples (10 μL droplets). Based on 16 working ultramicroelectrodes (UMEs) and 3 quasi-reference electrodes (QREs), a total of 48 sensors were engineered in a 3D crossbar arrangement that devised a low number of conductive lines.

Ultradense Electrochemical Chips with Arrays of Nanostructured Microelectrodes to Enable Sensitive Diffusion-Limited Bioassays.

Nanostructured microelectrodes (NMEs) are an attractive alternative to yield sensitive bioassays in unprocessed samples. However, although valuable for different applications, nanoporous NMEs usually cannot boost the sensitivity of diffusion-limited analyses because of the enlarged Debye length within the nanopores, which reduces their accessibility. To circumvent this limitation, nanopore-free gold NMEs were electrodeposited from 45 μm SU-8 apertures, featuring nanoridged microspikes on a recessed surface of gold thin film while carrying interconnected crown-like and spiky structures along the edge of a SU-8 passivation layer.

Predicting the formation of NADES using a transformer-based model.

The application of natural deep eutectic solvents (NADES) in the pharmaceutical, agricultural, and food industries represents one of the fastest growing fields of green chemistry, as these mixtures can potentially replace traditional organic solvents. These advances are, however, limited by the development of new NADES which is today, almost exclusively empirically driven and often derivative from known mixtures. To overcome this limitation, we propose the use of a transformer-based machine learning approach.

Single-Response Duplexing of Electrochemical Label-Free Biosensor from the Same Tag.

Multiplexing is a valuable strategy to boost throughput and improve clinical accuracy. Exploiting the vertical, meshed design of reproducible and low-cost ultra-dense electrochemical chips, the unprecedented single-response multiplexing of typical label-free biosensors is reported. Using a cheap, handheld one-channel workstation and a single redox probe, that is, ferro/ferricyanide, the recognition events taking place on two spatially resolved locations of the same working electrode can be tracked along a single voltammetry scan by collecting the electrochemical signatures of the probe in relation to different quasi-reference electrodes, Au (0 V) and Ag/AgCl ink (+0.

Correction: Removal of metals and inorganics from rendered fat using polyamine-modified cellulose nanocrystals.

[This corrects the article DOI: 10.1039/D3SU00116D.].

Removal of metals and inorganics from rendered fat using polyamine-modified cellulose nanocrystals.

Meatpacking and poultry operations produce an enormous amount of co-products including offal, fat, blood, feathers that are collected and processed by the rendering industry into value-added materials such as various protein meals and rendered fat products. Rendered fats (mainly composed of triglycerides from the adipose tissue of animals or used cooking oil from the restaurant industry) are sold for a variety of applications including animal feed formulations. Nonetheless, in the current context of energy scarcity, their use as feedstocks for the generation of renewable fuels including biodiesel and renewable diesel represents a growing market.

Predicting Antioxidant Synergism via Artificial Intelligence and Benchtop Data.

Lipid oxidation is a major issue affecting products containing unsaturated fatty acids as ingredients or components, leading to the formation of low molecular weight species with diverse functional groups that impart off-odors and off-flavors. Aiming to control this process, antioxidants are commonly added to these products, often deployed as combinations of two or more compounds, a strategy that allows for lowering the amount used while boosting the total antioxidant capacity of the formulation. While this approach allows for minimizing the potential organoleptic and toxic effects of these compounds, predicting how these mixtures of antioxidants will behave has traditionally been one of the most challenging tasks, often leading to simple additive, antagonistic, or synergistic effects.

Lab-on-a-Drone: remote voltammetric analysis of lead in water with real-time data transmission.

The present work describes a laboratory-on-a-drone (Lab-on-a-Drone) developed to perform detection of contaminants in environmental water samples. Toward this goal, the system was mounted on an unmanned aerial vehicle (UAV) (drone) and remotely controlled Wi-Fi to acquire a water sample, perform the electrochemical detection step, and then send the voltammetry data to a smartphone. This Lab-on-a-Drone system was also able to recharge its battery using a solar cell, greatly increasing the autonomy of the system, even in the absence of a power line.

Strategies for capillary electrophoresis: Method development and validation for pharmaceutical and biological applications-Updated and completely revised edition.

This review is in support of the development of selective, precise, fast, and validated capillary electrophoresis (CE) methods. It follows up a similar article from 1998, Wätzig H, Degenhardt M, Kunkel A. "Strategies for capillary electrophoresis: method development and validation for pharmaceutical and biological applications," pointing out which fundamentals are still valid and at the same time showing the enormous achievements in the last 25 years.

Advancements and future directions in cardiac biomarker detection using lateral flow assays.

Lateral flow assays (LFAs) have emerged as one of the most prominent paper-based biosensor platforms for rapidly detecting and quantifying analytes. Their selectivity, cost-effectiveness, efficiency, and simplicity make them ideal candidates for point-of-care (POC) applications, particularly when time-sensitive decisions are needed, such as cardiovascular events. The profound impact of cardiovascular diseases (CVDs), characterized by their high morbidity, mortality, and rehospitalization rates, necessitates an optimized approach for the early detection of cardiac muscle damage.

Rapid Detection of Using Paper-Derived Electrochemical Biosensors.

Several groups have recently explored the idea of developing electrochemical paper-based wearable devices, specifically targeting metabolites in sweat. While these sensors have the potential to provide a breadth of analytical information, there are several key challenges to address before these sensors can be widely adopted for clinical interventions. Toward this goal, we describe the development of a paper-based electrochemical sensor for the detection of .

Predicting the Orientation of Adsorbed Proteins Steered with Electric Fields Using a Simple Electrostatic Model.

Under the most common experimental conditions, the adsorption of proteins to solid surfaces is a spontaneous process that leads to a rather compact layer of randomly oriented molecules. However, controlling such orientation is critically important for the development of catalytic surfaces. In this regard, the use of electric fields is one of the most promising alternatives.

Dielectric Spectroscopy Can Predict the Effect of External AC Fields on the Dynamic Adsorption of Lysozyme.

This report describes the application of dielectric spectroscopy as a simple and fast way to guide protein adsorption experiments. Specifically, the polarization behavior of a layer of adsorbed lysozyme was investigated using a triangular-wave signal with frequencies varying from 0.5 to 2 Hz.

Taking the leap between analytical chemistry and artificial intelligence: A tutorial review.

The last 10 years have witnessed the growth of artificial intelligence into different research areas, emerging as a vibrant discipline with the capacity to process large amounts of information and even intuitively interact with humans. In the chemical world, these innovations in both hardware and algorithms have allowed the development of revolutionary approaches in organic synthesis, drug discovery, and materials' design. Despite these advances, the use of AI to support analytical purposes has been mostly limited to data-intensive methodologies linked to image recognition, vibrational spectroscopy, and mass spectrometry but not to other technologies that, albeit simpler, offer promise of greatly enhanced analytics now that AI is becoming mature enough to take advantage of them.

Use of universal 3D-Printed smartphone spectrophotometer to develop a time-based analysis for hypochlorite.

A fully-functional smartphone-based spectrophotometer was designed and built using 3D printing. The major advantage of this approach is its capacity to be interfaced with a variety of smartphones, allowing the use of the smartphone's camera and display, and regardless of the relative position of the camera. The analytical performance of the device was analyzed using a model dye (crystal violet), leading to a proportional response for concentrations in the 0.

Fast Degradation of Hydrogen Peroxide by Immobilized Catalase to Enable the Use of Biosensors in Extraterrestrial Bodies.

Hydrogen peroxide has been postulated to be present on the surface of Europa and Enceladus. While it could represent a potential source of energy for possible life-forms, HO may also interfere with a number of current detection technologies, including biosensors. To take advantage of the selectivity and portability of these devices, simple and reliable routes to degrade the potential HO present should be developed and implemented to prepare for this possibility.

A Multi-Pump Magnetohydrodynamics Lab-On-A-Chip Device for Automated Flow Control and Analyte Delivery.

This article shows the development of a computer-controlled lab-on-a-chip device with three magnetohydrodynamic (MHD) pumps and a pneumatic valve. The chip was made of a stack of layers of polymethylmethacrylate (PMMA), cut using a laser engraver and thermally bonded. The MHD pumps were built using permanent magnets (neodymium) and platinum electrodes, all of them controlled by an Arduino board and a set of relays.

Decomposition of Chemical Warfare Agent Simulants Utilizing Pyrolyzed Cotton Balls as Wicks.

A simple method to improve the thermal decomposition of chemical warfare agent simulants is reported. Utilizing pyrolyzed cotton balls as a substrate for the delivery of an incendiary agent into a bulk volume of chemical warfare agent simulants, significant enhancements in the burning rates were achieved with respect to either other wicks or the incendiary agent by itself. To perform the decomposition experiments and follow the reaction in real time, while still addressing the important safety considerations related to experiments involving chemical warfare agent simulants and incendiary agents, a simple instrument was assembled in a laboratory hood, where all experiments were performed.

Integrated instrumental analysis teaching platform with smartphone-operated fluorometer.

The present work describes an Integrated Teaching Tool (ITT) to facilitate the learning process in analytical chemistry. The first instrument integrated in the platform to demonstrate the concept is a wireless, portable fluorometer, produced by 3D printing. The low-cost instrument features a Teensy 3.

Fluorescent patterning of paper through laser engraving.

While thermal treatment of paper can lead to the formation of aromatic structures via hydrothermal treatment (low temperature) or pyrolysis (high temperature), neither of these approaches allow patterning the substrates. Somewhere in between these two extremes, a handful of research groups have used CO2 lasers to pattern paper and induce carbonization. However, none of the previously reported papers have focused on the possibility to form fluorescent derivatives via laser-thermal engraving.

Fabrication of microwell plates and microfluidic devices in polyester films using a cutting printer.

This study reports, for the first time, the possibility to manufacture analytical devices on polyester substrates using a cutting printer. The protocol involves the design of a layout in a graphical software, the cut into polyester films and the lamination against one or multiple polyester films coated with a thermosensitive layer. The feasibility of the proposed approach was demonstrated through the fabrication of 96-microwell plates, 3D microfluidic mixing and distance-based microfluidic devices.

Pyrolyzed cotton balls for protein removal: Analysis of pharmaceuticals in serum by capillary electrophoresis.

Because of the inherent affinity of proteins for bare, fused silica capillaries, the analysis of protein-containing samples has proven a challenging task for capillary electrophoresis. The adsorption of proteins to the capillary walls effectively changes the zeta potential and thus affects the electro-osmotic flow leading to significant shifts in migration time, peak broadening, and poor reproducibility. While there are several well-known methods to remove proteins from samples prior to the analysis (including precipitation) or to prevent their adsorption to the capillary (semi-permanent coatings), those approaches are often expensive, time consuming, or simply unreliable.

CO reduction using paper-derived carbon electrodes modified with copper nanoparticles.

The conversion of CO into useful chemicals can lead to the production of carbon neutral fuels and reduce greenhouse gas emissions. A key technological challenge necessary to enable such a process is the development of substrates that are active, cost effective, and selective for this reaction. In this regard, the reduction of CO electrochemical means is one of the most attractive alternatives but still requires rather unique electrodes.