Flexible and Conductive Bioelectrodes Based on Chitosan-Carbon Black Membranes: Towards the Development of Wearable Bioelectrodes.

Wearable sensors for non-invasive monitoring constitute a growing technology in many industrial fields, such as clinical or sport monitoring. However, one of the main challenges in wearable sensing is the development of bioelectrodes via the use of flexible and stretchable materials capable of maintaining conductive and biocompatible properties simultaneously. In this study, chitosan-carbon black (CH-CB) membranes have been synthesized using a straightforward and versatile strategy and characterized in terms of their composition and their electrical and mechanical properties.

Enzymatic Glucose-Based Bio-batteries: Bioenergy to Fuel Next-Generation Devices.

This article consists of a review of the main concepts and paradigms established in the field of biological fuel cells or biofuel cells. The aim is to provide an overview of the current panorama, basic concepts, and methodologies used in the field of enzymatic biofuel cells, as well as the applications of these bio-systems in flexible electronics and implantable or portable devices. Finally, the challenges needing to be addressed in the development of biofuel cells capable of supplying power to small size devices with applications in areas related to health and well-being or next-generation portable devices are analyzed.

Pacifier Biosensor: Toward Noninvasive Saliva Biomarker Monitoring.

Wearable sensors for noninvasive monitoring of physiological parameters is a growing technology in the clinical field. Especially in neonates, the development of portable and nonharmful monitoring devices is urgently needed because they cannot provide any feedback about discomfort or health complaints. However, in infant monitoring, only wearable sensors measuring physical parameters for vital signs have been developed.

Eyeglasses-based tear biosensing system: Non-invasive detection of alcohol, vitamins and glucose.

We report on a wearable tear bioelectronic platform, integrating a microfluidic electrochemical detector into an eyeglasses nose-bridge pad, for non-invasive monitoring of key tear biomarkers. The alcohol-oxidase (AOx) biosensing fluidic system allowed real-time tear collection and direct alcohol measurements in stimulated tears, leading to the first wearable platform for tear alcohol monitoring. Placed outside the eye region this fully wearable tear-sensing platform addresses drawbacks of sensor systems involving direct contact with the eye as the contact lenses platform.

Correction: Microchip in situ electrosynthesis of silver metallic oxide clusters for ultra-FAST detection of galactose in galactosemic newborns' urine samples.

Correction for 'Microchip in situ electrosynthesis of silver metallic oxide clusters for ultra-FAST detection of galactose in galactosemic newborns' urine samples by Laura García-Carmona et al., Analyst, 2016, 141, 6002-6007.

Class enzyme-based motors for "on the fly" enantiomer analysis of amino acids.

Here, two class-enzyme motors are properly designed allowing the rapid dispersion of the class-enzyme D-amino acid oxidase (DAO) and L-amino acid oxidase (LAO) for selective "on the fly" biodetection of D and L-amino acids (AAs), respectively. The efficient movement together with the continuous release of fresh class-enzyme leads to a greatly accelerated enzymatic reaction processes without the need of external stirring or chemical and physical attachment of the enzyme. Ultra-fast detection (<2min) and accurate quantifications of L-phenylalanine (L-Phe) in plasma and whole-blood newborns samples diagnosed with Phenylketonuria and total D-AAs in Vibrio cholera cultures are pioneer illustrated as relevant examples of each enantiomer determination.

Aligned copper nanowires as a cut-and-paste exclusive electrochemical transducer for free-enzyme highly selective quantification of intracellular hydrogen peroxide in cisplatin-treated cells.

The role and reliable quantification of intracellular hydrogen peroxide during cancer therapy constitutes an unexplored and fascinating application. In this work, we report the fabrication of vertically aligned copper nanowires (v-CuNWs) using electrosynthesis on templates, and their application as a cut-and-paste exclusive and flexible electrochemical transducer. This easily adaptable electrodic platform is demonstrated for a fast, simple and free-enzyme selective quantification of intracellular hydrogen peroxide in Cisplatin-treated human renal HK-2 cells.

Vertically-Oriented and Shape-Tailored Electrocatalytic Metal Nanowire Arrays for Enzyme-Free Galactosemia Rapid Diagnosis.

Metallic catalytic nanowires such as nickel and copper nanowires (NWs) for electrochemical detection of carbohydrates involved in metabolic rare diseases are proposed. NWs were electrodeposited using a polycarbonate membrane template, which was cut with the desired shape, stuck in double-sided adhesive tape, pasted into a non-conductive substrate and in situ removed. This simple and versatile approach allowed to obtain NWs vertically oriented (v-NWs), which are contained in the double-sided adhesive tape, becoming highly versatile.

Microchip in situ electrosynthesis of silver metallic oxide clusters for ultra-FAST detection of galactose in galactosemic newborns' urine samples.

This work describes for the first time the coupling of microfluidic chips (MC) to electrosynthetized silver metallic oxide clusters (AgMOCs). As an early demonstration of this novel approach, the ultrafast detection of galactose in galactosemic newborns' urine samples is proposed. AgMOCs were in situ electrosynthetized on integrated microchip platinum electrodes using a double pulse technique and characterized in full using scanning electronic microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS) and electrochemical techniques revealing the presence of silver oxides and electrocatalysis towards galactose as a galactosemia biomarker.

Electrochemical detectors based on carbon and metallic nanostructures in capillary and microchip electrophoresis.

Carbon and metallic-based nanostructures have been progressively implemented as innovative electrochemical detectors in CE and microchip electrophoresis (ME). For both type of nanomaterials and toward selected examples, this review details the impact of these nanomaterials for enhanced detection performance in CE, ME, and paper-based microfluidic devices. The analytical performance and the analytical potential in real world applications is also presented and discussed.