Scientific Highlights

This review is focused on publications dealing with interdigitated electrodes as a transducer unit and different bacteria detection systems using these devices. The first part of the review deals with the impedance technique principles, paying special attention to the use of interdigitated electrodes, while the main part of this work is focused on applications ranging from bacterial growth monitoring to label-free specific bacteria detection.
A review, Anal.Chim.Acta, 2019, vol.1088, pp. 1-19

This paper presents a new tool that allows a self-calibrating and multiplexed electrochemical lab-on-a-chip (ME-LoC) for cell culture analysis and high-resolution imaging. The ME-LoC contains a complex network of micro-channels and micro-chambers that allow compartmentalization of the reference electrode; cell seeding and proliferation without biofouling; electrode reactivation and recalibration; and multiple analyte detection, namely glucose and hydrogen peroxide concentrations, conductivity and ORP, as a way to monitor cell metabolism. Electrochemical analysis is completed with high-resolution imaging after labelling with fluorescent dyes. For its simplicity, integration, automation, compartmentalisation and microfluidic control, thist technology is a promising alternative for in vitro testing and organ-on-a-chip development in the near future.
Lab Chip, 2020, Advance Article

• Development of a robust electrochemical sensor integrated into a modular microfluidic system with the potential for on-site monitoring of inorganic As(III) species.
• Microfluidic system enabling the automatic sensor calibration, sample uptake, sample preconditioning and eventual As(III) detection.
• Linear system response to As(III) in a concentration range of 1−150 μg L−1, with a detection limit of 0.42 μg L−1 (below the threshold value of 10 μg L−1 set by WHO.
• System validated by measuring As(III) in tap water samples and samples from two Argentinean aquifers.

ACS Sensors, 2019, 4, 3156−3165

The remarkable advances in molecular logic reported in the last decade demonstrate the potential of luminescent molecules for logical operations, a paradigm-changing concerning silicon-based electronics. Trivalent lanthanide (Ln3+) ions, with their characteristic narrow line emissions, long-lived excited states, and photostability under illumination, may improve the state-of-the-art molecular logical devices. Here, the use of monolithic silicon-based structures incorporating Ln3+ complexes for performing logical functions is reported. Contrary to chemical inputs, physical inputs may enable the future concatenation of distinct logical functions and reuse of the logical devices, a clear step forward toward input–output homogeneity that is precluding the integration of nowadays molecular logic devices.
Adv. Optical Mater. 2020, 2000312.

We identify a program of forces and changes to the cytoplasmic mechanical properties required for mouse embryo development from fertilization to the first cell division. Injected, fully internalized chips responded to sperm decondensation and recondensation, and subsequent device behavior suggested a model for pronuclear convergence based on a gradient of effective cytoplasmic stiffness. The nanodevices reported reduced cytoplasmic mechanical activity during chromosome alignment and indicated that cytoplasmic stiffening occurred during embryo elongation, followed by rapid cytoplasmic softening during cell division. Forces greater than those inside muscle cells were detected. These results suggest that intracellular forces are part of a concerted program that is necessary for development at the origin of a new embryonic life.
Nat. Mater. (2020)

Here, we propose the integration of silicon nanowires on cell internalizable chips in order to combine the functional features of both approaches. The cellular uptake in HeLa cells of silicon 3 µm × 3 µm nanowire-based chips, and the results were compared with those of non-nanostructured silicon chips. Chip internalization without affecting cell viability was achieved however, important cell behavior differences were observed. The first stage of cell internalization was favored by silicon nanowire interfaces with respect to bulk silicon. In addition, chips were found inside membrane vesicles, and some nanowires seemed to penetrate the cytosol, which opens the door to the development of silicon nanowire chips as future intracellular sensors and drug delivery systems.
Nanomaterials 2020, 10(5), 893

The remarkable advances in molecular logic reported in the last decade demonstrate the potential of luminescent molecules for logical operations, a paradigm-changing concerning silicon-based electronics. Trivalent lanthanide (Ln3+) ions, with their characteristic narrow line emissions, long-lived excited states, and photostability under illumination, may improve the state-of-the-art molecular logical devices. Here, the use of monolithic silicon-based structures incorporating Ln3+ complexes for performing logical functions is reported. Contrary to chemical inputs, physical inputs may enable the future concatenation of distinct logical functions and reuse of the logical devices, a clear step forward toward input–output homogeneity that is precluding the integration of nowadays molecular logic devices.
Adv. Optical Mater. 2020, 2000312.