Future Medical Devices Research Articles

Reliable laser fabrication: the quest for responsive biomaterials surface.

Laser techniques have been traditionally used for material processing. Currently, there is growing recognition that lasers are a reliable fabrication tool that can be used to tailor the surfaces of biomaterials for tissue-engineering applications. Herein, we review the use of selected lasers with a wide range of wavelengths and pulses. We present typical examples to illustrate the basic fabrication principles and significance of laser fabrication in tailoring biomaterial surfaces with different geometric features. We also discuss the tissue-engineering applications of laser-fabricated biomaterials; these biomaterial surfaces show promise in delivering physicochemical cues for hard and soft tissue reconstruction.

O2 Reduction in Enzymatic Biofuel Cells.

Catalytic four-electron reduction of O2 to water is one of the most extensively studied electrochemical reactions due to O2 exceptional availability and high O2/H2O redox potential, which may in particular allow highly energetic reactions in fuel cells. To circumvent the use of expensive and inefficient Pt catalysts, multicopper oxidases (MCOs) have been envisioned because they provide efficient O2 reduction with almost no overpotential. MCOs have been used to elaborate enzymatic biofuel cells (EBFCs), a subclass of fuel cells in which enzymes replace the conventional catalysts. A glucose/O2 EBFC, with a glucose oxidizing anode and a O2 reducing MCO cathode, could become the in vivo source of electricity that would power sometimes in the future integrated medical devices. This review covers the challenges and advances in the electrochemistry of MCOs and their use in EBFCs with a particular emphasis on the last 6 years. First basic features of MCOs and EBFCs are presented. Clues provided by electrochemistry to understand these enzymes and how they behave once connected at electrodes are described. Progresses realized in the development of efficient biocathodes for O2 reduction relying both on direct and mediated electron transfer mechanism are then discussed. Some implementations in EBFCs are finally presented.

Study on the Factors Influencing User’s Acceptance Intention for Smart Medical and Health Care Equipment Based on UTAUT2

With the rapid development of mobile Internet technology and applications, more and more people begin to pay attention to and deepen the understanding of wearable devices, especially smart medical and health care devices. At the same time, as the extension of the traditional medical equipment, the market potential of smart medical and health care devices is huge, so it has also been paid more attention and promoted by many related industries and enterprises. However, according to the survey report, it shows that there is lower user adoption rate for the device's usage. In this study, we construct the user acceptance behavior model of smart medical and health care device, and analysis the factors influencing the adoption of smart medical and health care devices on the basis of UTAUT2 (the extended unified theory of acceptance and use of technology). In the study, we will pertinently modify the original UTAUT2 model, and add the two new constructs, including the health concern as the key features of health care equipment and the socio-economic status to carry on the research analysis. It aims to put forward suggestions on the operation and promotion of the future smart medical devices industry through the research in this paper.

TGF-β1 activation in human hamstring cells through growth factor binding peptides on polycaprolactone surfaces.

Our study describes the possibility to deliver hTGF-β1 to human derived hamstring cells using a non-covalent bioactive strategy. The significance of our results in vivo with our functionalized biomaterial with TGF-β1-binding peptides lies in the fact that these materials can now be employed to capture endogenous TGF-β1 in a spatially-controlled manner, overcoming the need for exogenous administration of supra-physiological TGF-β1 doses. Our method is different from current solutions that rely on global TGF-β1 administration, soaking the devices with TGF-β1, etc. Therefore we believe that our method is a significant change from current state-of-the-art in the types of devices that are used for ligament/tendon repair and that following our method can endow current and future medical devices with TGF-β1 binding properties.

Functional Nanoparticles Activate a Decellularized Liver Scaffold for Blood Detoxification

Extracorporeal devices have great promise for cleansing the body of virulence factors that are caused by venomous injuries, bacterial infections, and biological weaponry. The clinically used extracorporeal devices, such as artificial liver-support systems that are mainly based on dialysis or electrostatic interaction, are limited to remove a target toxin. Here, a liver-mimetic device is shown that consists of decellularized liver scaffold (DLS) populated with polydiacetylene (PDA) nanoparticles. DLS has the gross shape and 3D architecture of a liver, and the PDA nanoparticles selectively capture and neutralize the pore-forming toxins (PFTs). This device can efficiently and target-orientedly remove PFTs in human blood ex vivo without changing blood components or activating complement factors, showing potential application in antidotal therapy. This work provides a proof-of-principle for blood detoxification by a nanoparticle-activated DLS, and can lead to the development of future medical devices for antidotal therapy.

The Development of a New Medical Device for Standardized Episiotomy: A Pre-Clinical Validation Study

Background: The aim of this study was to present the validation and optimization process for a new innovative medical device to create a standardized episiotomy. Design: We performed a preclinical validation study. Setting: This study was performed at the University hospital. Sample: Animal, cadaver. Methods: Together with technical engineers, we designed a new medical device that involves a knife and cuts back from buttock toward introitus, in contrast to the conventional episiotomy. We optimized the design and its performance in consecutive animal and cadaver studies. Main Outcome Measures: Ability to perform a standardized incision, ease of use. Results: After multiple adjustments, based on the results of multiple animal and cadaver studies, a medical device was developed to perform a standardized clean-cut episiotomy of 4-6 cm length. Conclusion: We have shown that optimizing the technical performance and safety of an innovative device in animals, prior to opposing patients to its potential hazards, is feasible. Our design optimizing study can be used as a model for the pre-clinical validation of future innovative medical devices.

Foreign direct investment of Covidien Center of Innovation in medical device industry

Medical device industry has characteristics of multi-disciplinary convergence and is easy to apply with information communication technology. Such nature makes Korea medical device industry more globally competitive than the pharmaceutical industry. The foreign direct investment (FDI) of service industry in Korea continues to be at a standstill and the medical device industry is not an exception. Among this stagnant FDI situation in Korea, Covidien, a global medical device company has established the Covidien Center of Innovation as both an education and training facility for domestic and foreign healthcare professionals and a medical device research and development (R&D) center in August 2013. Along with the global attractiveness of superior clinical outcomes generated by healthcare professionals, the future medical device industry development will be fueled by continued R&D investments, researchoriented hospital R&D activities, and clinical studies, etc. It is important to provide attractive investment environments to embrace FDI similar to Covidien Center of Innovation into Korea in order to leverage healthcare professionals' competency at maximum and lead collaboration between medical device companies and healthcare professionals. It is imperative that 'innovative medical device enterprise' certification system similar to the curent 'innovative pharmaceutical enterprise certification' is created. If additional premium reimbursement prices are granted to medical devices developed and manufactured by the innovative enterprises which contribute to domestic R&D and healthcare professional education and training through FDI in Korea, it will help FDI activation in Korea to a great extent. And the reimbursement coverage for routine care costs in clinical trial will stimulate FDI in Korea.

Modeling and Simulation of Enzymatic Biofuel Cells with Three-Dimensional Microelectrodes

The enzymatic biofuel cells (EBFCs) are considered as an attractive candidate for powering future implantable medical devices. In this study, a computational model of EBFCs based on three-dimensional (3-D) interdigitated microelectrode arrays was conducted. The main focus of this research is to investigate the effect of different designs and spatial distributions of the microelectrode arrays on mass transport of fuels, enzymatic reaction rate, open circuit output potential and current density. To optimize the performance of the EBFCs, numerical simulations have been performed for cylindrical electrodes with various electrode heights and well widths. Optimized cell performance was obtained when the well width is half of the height of the 3-D electrode. In addition, semi-elliptical shaped electrode is preferred based on the results from current density and resistive heating simulation.

Disease-specific guidelines for reporting adverse events for peripheral vascular medical devices

Disease-specific guidelines for reporting adverse events for peripheral vascular medical devices

Travelling along the Clinical Roadmap: Developing Electrospun Scaffolds for Tendon Repair

Biopolymers, such as poly(ε-caprolactone), can be easily electrospun to create fibrous scaffolds. It is also possible to control the alignment of the emitted fibres and further manipulate these scaffolds to create 3D yarn structures, which resemble part of the tendon tissue hierarchy. Material properties, such as tensile strength, can be tailored depending on the selection and combination of polymer and solvent used during electrospinning. The scaffolds have been proven to separately support the adhesion and proliferation of equine tendon fibroblasts and human mesenchymal stem cells whilst simultaneously directing cell orientation, which caused their alignment parallel to the underlying fibres. Implantation of scaffolds into the flexor digitorum profundus tendon of mice hindpaws yielded encouraging results with minimal inflammatory reaction and observation of cell infiltration into the scaffold. This research demonstrates the progression of electrospun fibres along the clinical roadmap towards becoming a future medical device for the treatment of tendon injuries.

Implantable Biofuel Cells Operating In Vivo – towards Biomedical Devices Powered with Electricity Harvested Inside the Body

not Available.

O014: A new generation of hybrid biomaterials for antimicrobial medical devices

The present effective treatment for device related infections is large doses of systemically applied drugs. There is a high risk of recurring infections and biofilm formation for patients dependent on long term in-dwelling catheters and the extended dependency on antibiotics results in clinical drug resistance. We present a new tool for minimizing drug resistance by upgrading existing and future medical devices through a unique self-regenerating surface that prevents biofilm formation.

From “cyborg” lobsters to a pacemaker powered by implantable biofuel cells

Enzyme-based biofuel cells implanted into living lobsters or designed as fluidic systems mimicking human blood circulation were used for powering electronic devices. Two lobsters with implanted biofuel cells connected in series were able to generate open circuit voltage (Voc) up to 1.2 V and an electrical watch, selected as a model electronic device, was activated by the power extracted from the “living battery”. The fluidic system composed of five cells filled with human serum solution connected in series generated Voc of ca. 3 V and was able to power a pacemaker. Sustainable operation of the pacemaker was achieved with the system closely mimicking human physiological conditions characteristic of normal and pathophysiological glucose concentrations with the fluidic rate typical for a blood circulation upon resting or performing physical exercises. While the “cyborg” lobsters demonstrate a model system with future possible military, homeland security and environmental monitoring applications, the system activating a pacemaker presents practicality for biomedical applications. The first demonstration of the pacemaker activated by the physiologically produced electrical energy shows promise for future electronic implantable medical devices powered by electricity harvested from the human body.

A pacemaker powered by an implantable biofuel cell operating under conditions mimicking the human blood circulatory system – battery not included

Biocatalytic electrodes made of buckypaper were modified with PQQ-dependent glucose dehydrogenase on the anode and with laccase on the cathode and were assembled in a flow biofuel cell filled with serum solution mimicking the human blood circulatory system. The biofuel cell generated an open circuitry voltage, Voc, of ca. 470 mV and a short circuitry current, Isc, of ca. 5 mA (a current density of 0.83 mA cm(-2)). The power generated by the implantable biofuel cell was used to activate a pacemaker connected to the cell via a charge pump and a DC-DC converter interface circuit to adjust the voltage produced by the biofuel cell to the value required by the pacemaker. The voltage-current dependencies were analyzed for the biofuel cell connected to an Ohmic load and to the electronic loads composed of the interface circuit, or the power converter, and the pacemaker to study their operation. The correct pacemaker operation was confirmed using a medical device - an implantable loop recorder. Sustainable operation of the pacemaker was achieved with the system closely mimicking human physiological conditions using a single biofuel cell. This first demonstration of the pacemaker activated by the physiologically produced electrical energy shows promise for future electronic implantable medical devices powered by electricity harvested from the human body.

Characteristic and Modeling of Human Body Motions for Body Area Network Applications

Many current and future medical devices are wearable and human body is used as a carrier for wireless communication, which implies human body to be a crucial part of the transmission medium in body area networks (BANs). In order to understand the propagation characteristics around human body, the statistical model is derived for communication links in the medical implant communication service band, industrial scientific medical band and ultra-wideband based on the narrowband measurement. The channel model of diffracting components around human body were different from one scenario to another. Moreover, second order statistics, including level crossing rate and fade duration, are presented for each scenario to evaluate the link quality and outage performance for on-body to on-body scenario. Using a network analyzer, Doppler spread spectrum in frequency domain and coherence time in time domain from temporal variations of human body movements are also analyzed from diverse perspectives. Additionally, the shape of Doppler spread spectrum is fitted to describe the relationship of power and frequency. The proposed on-body to on-body channel model for human body motions can be used to better design wireless network protocols for BANs.

Advances in Medical Devices and Medical Electronics

Medical devices and medical electronics are areas that had little to offer 100 years ago. However, there were three important existing technologies that led to many further developments over the following 100 years. These are the stethoscope, electrocardiography, and X-ray medical imaging. Although these technologies had been described and were available to some extent when the Proceedings of the IEEE pages first appeared, they had yet to achieve the widespread use that they have today. The stethoscope is the oldest of these, and it helped physicians to hear sounds of the body and relate them to functioning and malfunctioning organs. The early use of the stethoscope by physicians was more of an art than a science, but as the Proceedings matured, so did this technology. Engineers were able to make this a more quantitative process by graphically displaying the sounds and ultimately using techniques such as voiceprint analysis to assist the physician in diagnosis and monitoring of treatment. The electrocardiograph had been invented a few years prior to the appearance of the Proceedings, but the apparatus was awkward to use, especially for sick people, and was considered more of an oddity than a viable medical technology 100 years ago. Today, it and devices derived from it such as cardiac patient monitors are important parts of our healthcare system. Similarly, X-rays represented a new technology 100 years ago, but unlike electrocardiography physicians immediately saw the value of this technology and quickly adopted it. Many improvements have been made to the basic technology over the last 100 years culminating in computer tomography and complex image processing. Other devices to create high-quality and 3-D medical images have also been developed in recent years to make medical imaging a very important aspect of clinical care today. Looking to the future is always a difficult task, but it is clear that the electronic health record will play an important role in consolidating the information from various medical devices as well as providing readily available data on patients wherever it might be needed. Future medical devices will need to not only address the problems of diagnostic and therapeutic medicine but also be capable of addressing important societal problems such as worldwide disparities in the availability of medical care, continually rising healthcare costs, and healthcare for travel beyond Earth. The next 100 years promises to be even more exciting than the last from the perspective of medical devices and medical electronics.

Gamma irradiation of electrospun poly(ε‐caprolactone) fibers affects material properties but not cell response

AbstractFabrication of electrospun fibrous scaffolds as future medical devices is being widely researched, with particular emphasis given to their material properties and effect on cell response and differentiation. However, the vast majority of these scaffolds are sterilized via nonmedically approved methods, including submersion in ethanol and exposure to UV light. Although these techniques are adequate for laboratory‐based research, they are not sufficient for human implantation. In this case, regulatory approved, medical grade sterilization is required. In this study, we report the effects of gamma irradiation, a regulatory approved technique, on electrospun poly(ε‐caprolactone) fibers. Fabricated fibers were separately subjected to different dosages of irradiation ranging from 0 to 45 kGy and then assessed for their physicochemical properties. Gamma irradiation affected fiber properties irrespective of dosage. A dose‐dependent decrease in polymer molecular weight was observed and an increase in melting point and crystallinity reported. Similarly, irradiation had a significant effect on mechanical properties with greatest decrease in tensile strength (68%) for fibers exposed to 40 kGy. The method of sterilization had no effect on cell response. Seeded tenocytes attached to all fibers and elongated parallel to the underlying fiber direction. The results demonstrate the importance of incorporating medical grade sterilization procedures early in the research projects time line to assist translation from bench to clinic. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012

A Method for Removal of Low Frequency Components Associated with Head Movements from Dual-Axis Swallowing Accelerometry Signals

Head movements can greatly affect swallowing accelerometry signals. In this paper, we implement a spline-based approach to remove low frequency components associated with these motions. Our approach was tested using both synthetic and real data. Synthetic signals were used to perform a comparative analysis of the spline-based approach with other similar techniques. Real data, obtained data from 408 healthy participants during various swallowing tasks, was used to analyze the processing accuracy with and without the spline-based head motions removal scheme. Specifically, we analyzed the segmentation accuracy and the effects of the scheme on statistical properties of these signals, as measured by the scaling analysis. The results of the numerical analysis showed that the spline-based technique achieves a superior performance in comparison to other existing techniques. Additionally, when applied to real data, we improved the accuracy of the segmentation process by achieving a 27% drop in the number of false negatives and a 30% drop in the number of false positives. Furthermore, the anthropometric trends in the statistical properties of these signals remained unaltered as shown by the scaling analysis, but the strength of statistical persistence was significantly reduced. These results clearly indicate that any future medical devices based on swallowing accelerometry signals should remove head motions from these signals in order to increase segmentation accuracy.

An enhanced frame transmission method for medical devices with ultra low power operation

Radio modules for future medical devices are required to minimize their energy consumption while maximizing the reliability of frame transmission. For medical devices in wireless body network, TDMA-based protocols can be candidates, but they have low energy efficiency in a wireless interference environment. In this paper, we propose an enhanced continuous frame transmission (CFT) method which is a hybrid TDMA and random access MAC protocol with carrier sensing method. CFT controls the frame transmission epochs considering the effect of interference that changes according to the number of neighbor wireless devices. Simulation results show that CFT method has higher efficiency compared to conventional TDMA based methods in a interference environment.

One-pot Synthesis of TiO2 Nanoparticles in Suspensions for Quantification of Titanium Debris Release in Biological Liquids

In this work we have developed an analytical method to measure potential titanium debris released from TiO2 nanotube layers devices immersed in biological fluids. This quantitative study is highly required to ensure both the security and non toxicity of the nanostructured surfaces used as future implantable medical devices in the living. A one-pot synthesis process is developed to produce high quality standard solutions of titanium dioxide nanoparticles in aqueous medium. The elaborated dispersion is then used to fabricate standard solutions in both aqueous and human blood plasma media. The synthesized nanoparticles dispersion was characterized by granulometry. The nanoparticles structure and morphology were then observed using Transmission Electron Microscopy (TEM). Thermogravimetric Analysis (TGA) was used to evaluate the concentration of TiO2 in the suspension. A quantitative routine by the use of Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) is developed. The quantification threshold of titanium species is found to be in the 30 - 40 ppb range. None interference is detected between the particles and the human blood plasma. Using the established quantitative routine, the titanium species release from titania nanotube layers in human blood plasma is evaluated.