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

Design of Non Invasive Wireless Eeg Recording System

Bio medical signal monitoring systems have drawn great attention now a day by the results yielded from weighty advances in electronics and communications and field of information technologies. As an example EEG (electroencephalogram) is the most popular interface for measuring bio-potential in brain computer interface (BCI) systems which is a prominent topic organizing a direct communication link between human brain and a computer. We know that most BCI (brain computer interface) systems are bulky and hard wired EEG experiments which are inconvenient and troublesome for patients to follow their regular routine tasks. So, to overcome this problem we are going to develop a single channel wireless EEG (electroencephalogram) acquisition and recording system which will be more comfortable and convenient to the patients. The system consists of an EEG signal acquisition and processing units along with the wireless transmission and reception units. The former (analogue processing unit) includes electrodes, pre-amplifiers, filters and gain amplifiers while the later (digital processing unit) includes ADC (analogue to digital converter) and micro-controller which are used to convert the analogue EEG signals into digital signals and fulfill the digital filtering. The transmission and reception units include a Bluetooth communication module which sends the digital signals to the PC (personal computer) to be displayed over the GUI (graphical user interface). Thus the patient's EEG signal could be observed and stored without any bulky wired environment due to which the distortion caused by the long distance transmission could be reduced significantly. The key performances are: a) Long range communications (50 meters) b) ADC sampling rate is high (400 samples/sec) c) Low power consumption. d) Portable and e) Battery operated. Medical research applications based on wireless EEG acquisition system can be explored such as brain controlled games and diagnosis of diseases

Design, implementation, evaluation and application of a 32-channel radio frequency signal generator for thermal magnetic resonance based anti-cancer treatment

Thermal Magnetic Resonance (ThermalMR) leverages radio frequency (RF)-induced heating to examine the role of temperature in biological systems and disease. To advance RF heating with multi-channel RF antenna arrays and overcome the shortcomings of current RF signal sources, this work reports on a 32-channel modular signal generator (SG(PLL)). The SG(PLL) was designed around phase-locked loop (PLL) chips and a field-programmable gate array chip. To examine the system properties, switching/settling times, accuracy of RF power level and phase shifting were characterized. Electric field manipulation was successfully demonstrated in deionized water. RF heating was conducted in a phantom setup using self-grounded bow-tie RF antennae driven by the SG(PLL). Commercial signal generators limited to a lower number of RF channels were used for comparison. RF heating was evaluated with numerical temperature simulations and experimentally validated with MR thermometry. Numerical temperature simulations and heating experiments controlled by the SG(PLL) revealed the same RF interference patterns. Upon RF heating similar temperature changes across the phantom were observed for the SG(PLL) and for the commercial devices. To conclude, this work presents the first 32-channel modular signal source for RF heating. The large number of coherent RF channels, wide frequency range and accurate phase shift provided by the SG(PLL) form a technological basis for ThermalMR controlled hyperthermia anti-cancer treatment

A multi-chanel electrical impedance meter based on digital lock-in technology

Abstract The presented multichannel measuring system working on various frequencies is suitable either for electrical impedance spectroscopy or tomography. The authors of this paper have developed the complete measurement system and a graphical user interface platform. The accuracy of impedance amplitude and phase are 1 ppm and 0.01°, respectively. The basic instrument works with 8 channels and can be expanded to 64 channels with the application of multiplexing or multiple parallel connected instruments in the same system

Design and development of a novel Invasive Blood Pressure simulator for patient's monitor testing

This paper presents a newly-designed and realized Invasive Blood Pressure (IBP) device for the simulation on patient’s monitors. This device shows improvements and presents extended features with respect to a first prototype presented by the authors and similar systems available in the state-of-the-art. A peculiarity of the presented device is that all implemented features can be customized from the developer and from the point of view of the end user. The realized device has been tested, and its performances in terms of accuracy and of the back-loop measurement of the output for the blood pressure regulation utilization have been described. In particular, an accuracy of ±1 mmHg at 25 °C, on a range from −30 to 300 mmHg, was evaluated under different test conditions. The designed device is an ideal tool for testing IBP modules, for zero setting, and for calibrations. The implemented extended features, like the generation of custom waveforms and the Universal Serial Bus (USB) connectivity, allow use of this device in a wide range of applications, from research to equipment maintenance in clinical environments to educational purposes. Moreover, the presented device represents an innovation, both in terms of technology and methodologies: It allows quick and efficient tests to verify the proper functioning of IBP module of patients’ monitors. With this innovative device, tests can be performed directly in the field and faster procedures can be implemented by the clinical maintenance personnel. This device is an open source project and all materials, hardware, and software are fully available for interested developers or researchers.Web of Science201art. no. 25

A high-performance 8 nV/root Hz 8-channel wearable and wireless system for real-time monitoring of bioelectrical signals

Background: It is widely accepted by the scientific community that bioelectrical signals, which can be used for the identification of neurophysiological biomarkers indicative of a diseased or pathological state, could direct patient treatment towards more effective therapeutic strategies. However, the design and realisation of an instrument that can precisely record weak bioelectrical signals in the presence of strong interference stemming from a noisy clinical environment is one of the most difficult challenges associated with the strategy of monitoring bioelectrical signals for diagnostic purposes. Moreover, since patients often have to cope with the problem of limited mobility being connected to bulky and mains-powered instruments, there is a growing demand for small-sized, high-performance and ambulatory biopotential acquisition systems in the Intensive Care Unit (ICU) and in High-dependency wards. Finally, to the best of our knowledge, there are no commercial, small, battery-powered, wearable and wireless recording-only instruments that claim the capability of recording electrocorticographic (ECoG) signals. Methods: To address this problem, we designed and developed a low-noise (8 nV/√Hz), eight-channel, battery-powered, wearable and wireless instrument (55 × 80 mm2). The performance of the realised instrument was assessed by conducting both ex vivo and in vivo experiments. Results: To provide ex vivo proof-of-function, a wide variety of high-quality bioelectrical signal recordings are reported, including electroencephalographic (EEG), electromyographic (EMG), electrocardiographic (ECG), acceleration signals, and muscle fasciculations. Low-noise in vivo recordings of weak local field potentials (LFPs), which were wirelessly acquired in real time using segmented deep brain stimulation (DBS) electrodes implanted in the thalamus of a non-human primate, are also presented. Conclusions: The combination of desirable features and capabilities of this instrument, namely its small size (~one business card), its enhanced recording capabilities, its increased processing capabilities, its manufacturability (since it was designed using discrete off-the-shelf components), the wide bandwidth it offers (0.5 – 500 Hz) and the plurality of bioelectrical signals it can precisely record, render it a versatile and reliable tool to be utilized in a wide range of applications and environments

Monitoring Cardiovascular Physiology using Bio-compatible AlN Piezoelectric Skin Sensors

Arterial pulse waves contain a wealth of parameters indicative of cardiovascular disease. As such, monitoring them continuously and unobtrusively can provide health professionals with a steady stream of cardiovascular health indices, allowing for the development of efficient, individualized treatments and early cardiovascular disease diagnosis solutions. Blood pulsations in superficial arteries cause skin surface deformations, typically undetectable to the human eye; therefore, Microelectromechanical systems (MEMS) can be used to measure these deformations and thus create unobtrusive pulse wave monitoring devices. Miniaturized ultrathin and flexible Aluminium Nitride (AlN) piezoelectric MEMS are highly sensitive to minute mechanical deformations, making them suitable for detecting the skin deformations caused by cardiac events and consequently providing multiple biomarkers useful for monitoring cardiovascular health and assessing cardiovascular disease risk. Conventional wearable continuous pulse wave monitoring solutions are typically large and based on technologies limiting their versatility. Therefore, we propose the adoption of 29.5 μm-thick biocompatible, skin-conforming devices on piezoelectric AlN to create versatile, multipurpose arterial pulse wave monitoring devices. In our initial trials, the devices are placed over arteries along the wrist (radial artery), neck (carotid artery), and suprasternal notch (on the chest wall and close to the ascending aorta). We also leverage the mechano-acoustic properties of the device to detect heart muscle vibrations corresponding to heart sounds S1 and S2 from the suprasternal notch measurement site. Finally, we characterize the piezoelectric device outputs observed with the cardiac cycle events using synchronized electrocardiogram (ECG) reference signals and provide information on heart rate, breathing rate, and heart sounds. The extracted parameters strongly agree with reference values as illustrated by minimum Pearson correlation coefficients (r) of 0.81 for pulse rate and 0.95 for breathing rate

New Approach for Making Standard the Development of Biosensing Devices by a Modular Multi-Purpose Design

The fast widening of biosensing applications, such as healthcare, drug delivery, food, and military industries, is increasing the need for generality and compatibility among different sensors. To address this challenge, we present here an innovative approach for the fast development of new electronic biosensing systems, linking a custom-designed front-end with a multi-purpose system. We envision an open tool to help designers to focus on the target molecule and related detection method instead of designing each time a dedicated electronic device. The architecture of the proposed system is based on a modular approach, where only the front-end and the software need to be custom re-designed according to the application. Considering current research and applying a rigorous definition of the technical requirements, the core of the system is designed to fit the highest number of biosensing methods. The flexibility of this approach is successfully demonstrated with three different types of biosensors, i.e., amperometric, ion-sensitive, and memristive

Bidirectional Wireless Telemetry for High Channel Count Optogenetic Microsystems

In the past few decades, there has been a significant progress in the development of wireless data transmission systems, from high data rate to ultra-low power applications, and from G-b per second to RFID systems. One specific area, in particular, is in wireless data transmission for implantable bio-medical applications. To understand how brain functions, neural scientists are in pursuit of high-channel count, high-density recordings for freely moving animals; yet wire tethering issue has put the mission on pause. Wireless data transmission can address this tethering problem, but there are still many challenges to be conquered. In this work, an ultra-low power ultra-wide band (UWB) transmitter with feedforward pulse generation scheme is proposed to resolve the long-existing problem in UWB transmitter. It provides a high-data rate capability to enable 1000 channels in broadband neural recording, assuming 10-bit resolution with a sampling rate of 20 kHz to accommodate both action potential (AP) and local field potential (LFP) recording, while remaining in ultra- low power consumption at 4.32 pJ/b. For the bi-directional communication between the wireless and recording/ stimulating module, a bit-wise time-division (B-TDD) duplex transceiver without cancellation scheme is presented. The receiver works at U-NII band (5.2GHz) and shares the same antenna with UWB transmitter. This significantly reduces the area consumption as well as power consumption for implantable systems. The system can support uplink at 200 Mbps for 1000 recording channels and downlink at 10 Mbps for 36 stimulation channels. With a 3.7 Volt 25mAh rechargeable battery, the system should be able to operate more than 1.5 hours straight for both recording and stimulation, assuming 1 LED channel with 100 µA, 10% duty-cycled stimulating current. The B-TDD transceiver is integrated with a dedicated recording/ stimulation optogenetic IC chip to demonstrate as a complete wireless system for implantable broadband optogenetic neural modulation and recording. The fully integrated system is less than 5 gram, which is suitable for rodent experiments.PHDElectrical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/155242/1/yujulin_1.pd

Information management system study results. Volume 1: IMS study results

The information management system (IMS) special emphasis task was performed as an adjunct to the modular space station study, with the objective of providing extended depth of analysis and design in selected key areas of the information management system. Specific objectives included: (1) in-depth studies of IMS requirements and design approaches; (2) design and fabricate breadboard hardware for demonstration and verification of design concepts; (3) provide a technological base to identify potential design problems and influence long range planning (4) develop hardware and techniques to permit long duration, low cost, manned space operations; (5) support SR&T areas where techniques or equipment are considered inadequate; and (6) permit an overall understanding of the IMS as an integrated component of the space station