Pere Miribel-Català

Smart Power Integrated Circuit for a Piezoelectric Miniature Robot

A BCD technology (Bipolar, CMOS, DMOS) is used to implement a high voltage smart power integrated circuit in order to obtain a fully integrated Smart Powered Piezoactuator Unit (SPU) for a new generation of miniature robots with sizes around 1 cm3. The integrated circuit is based on a mixed-mode circuit with power analogue output circuitry and digital input control circuitry. A specific driving system strategy is defined based on ICs assembled on-board with a serial communication interface. This minimizes the number of wires connecting the miniature robot to improve the robot motion performances and is a first step towards fully autonomy. Six samples of the ICs have been assembled onto a driving platform and tested with good results.

Combined dielectrophoretic and impedance system for on-chip controlled bacteria concentration: Application to Escherichia coli

The present paper reports a bacteria autonomous controlled concentrator prototype with a user‐friendly interface for bench‐top applications. It is based on a microfluidic lab‐on‐a‐chip and its associated custom instrumentation, which consists of a dielectrophoretic actuator, to preconcentrate the sample, and an impedance analyzer, to measure concentrated bacteria levels. The system is composed of a single microfluidic chamber with interdigitated electrodes and an instrumentation with custom electronics. The prototype is supported by a real‐time platform connected to a remote computer, which automatically controls the system and displays impedance data used to monitor the status of bacteria accumulation on‐chip. The system automates the whole concentrating operation. Performance has been studied for controlled volumes of Escherichia coli samples injected into the microfluidic chip at constant flow rate of 10 μL/min. A media conductivity correcting protocol has been developed, as the preliminary results showed distortion of the impedance analyzer measurement produced by bacterial media conductivity variations through time. With the correcting protocol, the measured impedance values were related to the quantity of bacteria concentrated with a correlation of 0.988 and a coefficient of variation of 3.1%. Feasibility of E. coli on‐chip automated concentration, using the miniaturized system, has been demonstrated. Furthermore, the impedance monitoring protocol had been adjusted and optimized, to handle changes in the electrical properties of the bacteria media over time.

Design of a customized multipurpose nano-enabled implantable system for in-vivo theranostics

The first part of this paper reviews the current development and key issues on implantable multi-sensor devices for in vivo theranostics. Afterwards, the authors propose an innovative biomedical multisensory system for in vivo biomarker monitoring that could be suitable for customized theranostics applications. At this point, findings suggest that cross-cutting Key Enabling Technologies (KETs) could improve the overall performance of the system given that the convergence of technologies in nanotechnology, biotechnology, micro&nanoelectronics and advanced materials permit the development of new medical devices of small dimensions, using biocompatible materials, and embedding reliable and targeted biosensors, high speed data communication, and even energy autonomy. Therefore, this article deals with new research and market challenges of implantable sensor devices, from the point of view of the pervasive system, and time-to-market. The remote clinical monitoring approach introduced in this paper could be based on an array of biosensors to extract information from the patient. A key contribution of the authors is that the general architecture introduced in this paper would require minor modifications for the final customized bio-implantable medical device.

Dielectrophoretic concentrator enhancement based on dielectric poles for continuously flowing samples.

We describe a novel continuous‐flow cell concentrator microdevice based on dielectrophoresis, and its associated custom‐made control unit. The performances of a classical interdigitated metal electrode‐based dielectrophoresis microfluidic device and this enhanced version, that includes insulator‐based pole structures, were compared using the same setup. Escherichia coli samples were concentrated at several continuous flows and the devices trapping efficiencies were evaluated by exhaustive cell counts. Our results show that pole structures enhance the retention up to 12.6%, obtaining significant differences for flow rates up to 20 μL/min, when compared to an equivalent classical interdigitated electrodes setup. In addition, we performed a subsequent proteomic analysis to evaluate the viability of the biological samples after the long exposure to the actuating electrical field. No Escherichia coli protein alteration in any of the two systems was observed.

Self-powered adaptive circuit sampling for a piezoelectric harvester

This paper proposes a low-cost true self-powered start-up and control circuitry for an envisaged system based on commercial vibration energy harvesting sources, that is oriented to structural health monitoring (SHM) applications. The proposed circuitry is quite simple and assures a battery less system just working with piezoelectrical generators. This architecture works looking for the maximum mechanical to electrical efficiency conversion, thanks to a continuous check of the open-load voltage at the piezoelectric generator, disconnecting it from the electronic circuitry, defining a true adaptive control unit. Also it is addressed the cold-start of the system. Initial experimental results are provided to verify its performance.

Low-ripple skipping-based regulation system for a two-phase voltage doubler charge pump

A full-custom regulated two-phase voltage doubler charge pump is presented in this paper. The regulation process is based on the use of a comparator-based pulse-skipping regulator. Since this type of regulation generates an inherent and non-negligible amount of ripple over the regulated output voltage, an on-chip ripple reduction system has been developed and included in the charge pump architecture. Simulated results show that ripple reduction ratios up to 53% can be achieved when the designed ripple reduction solution is applied over a 5 V regulated charge pump with flying and load capacitors Cf=CL=1 uF, switching frequency fs=100 kHz, and load RL=10 KΩ. The proposed design has been implemented using the high-voltage I2T100 0.7µm BCD smart power technology.

Small-volume multiparametric electrochemical detection at low cost polymeric devices featuring nanoelectrodes

The development of a low-cost multiparametric platform for enzymatic electrochemical biosensing that can be integrated in a disposable, energy autonomous analytical device is the target of the current work. We propose a technology to fabricate nano-electrodes and ultimately biosensors on flexible polymeric-based substrates (cyclo olefin polymer, and polyimide) using standard microfabrication (step and repeat lithography and lift-off) and rapid prototyping techniques (blade cutting). Our target is towards the fabrication of a miniaturized prototype that can work with small sample volumes in the range of 5-10μL without the need for external pumps for sample loading and handling. This device can be used for the simultaneous detection of metabolites such as glucose, cholesterol and triglycerides for the early diagnosis of diabetes.

Towards a portable point-of-use blood analysis with EIS technique device

In this paper first approach to a compact system for point-of-use primarily blood characteristics analysis by means of an EIS (Electrochemical Impedance Spectroscopy) experience is described. This is based on a custom electronic instrumentation, post processing software and a commercial three electrodes gold sensor. The designed electronic is based on a potentiostat instrumentation supported by a real time platform connected to a remote computer, which allows the instrumentation control, real time monitoring data and its posterior resultant analysis. Moreover, the whole system has been characterized and validated using different sensors and biocompatible materials. The study consists on a complete EIS experience in order to get a full spectrum analysis of impedance behavior in terms of magnitude and phase. As a result, we were able to detect impedance with an average error of less than 3% and a SNR rejection of -40 dB in a frequency working range of 10 Hz to 100 kHz. This integrated approach pushes forward the development of truly autonomous point-of-care devices relying on impedance spectrometry detection.

Accurate design of Two-Phase Voltage Doublers based on a compact mathematical model

A novel accurate mathematical model to be applied in the steady-state analysis of Two-Phase Voltage Doubler circuits is presented. The use of this model in combination with numerical software tools provides a full understanding about the voltage doublers steady-state output behavior while, at the same time, accelerates and simplifies the design process of such circuits in comparison with the use of classical parametric SPICE-based simulations. Numerically simulated results show that the proposed model is closer to the SPICE-based simulation data than already developed models, offering less than 1% of relative error over a wide range of working load conditions.

A portable point-of-care device for multi-parametric diabetes mellitus analysis

We present a small, compact and portable envisaged lab-on-a-chip (LoC) device for point-of-care (PoC) detection of different key parameters on diabetes mellitus analysis; glucose, cholesterol, triglycerides and hematocrit. These four parameters, present in blood samples, are important in the standardized analysis affecting different patients with different medical conditions. The quantification of glucose, cholesterol, triglycerides and hematocrit it is performed with a single disposable device using a single blood drop, enhancing disposition decision time and improving patient satisfaction when compared with actual analytical methodology, and it is an easy to use device and no skilled personnel is needed to use it, avoiding the use of more complicated processes like phlebotomy. The presented device consists of a custom sensing system, low power electronic instrumentation and an easy user interpretation readout display, powered by a single battery.