A study revealed at this year’s Heart Rhythm Society Meeting presented the first in-human results of a leadless implantable pacemaker. The device is about the size of a AAA battery and is implanted in the right ventricle. A limitation of current pacemakers is the reliance on implantable leads that can fracture or become infected. This device is the first step toward developing leadless pacing technologies. It remains to be seen how clinically useful this device will be but is expected to be available in Europe later this year.

Pharmaco-Kinesis Corporation has developed an implantable pump for localized cancer-fighting drug delivery. This first-generation Nano-Impedance Biosensor (NIB) detects vascular endothelial growth factor (VEGF-165) which is a biomarker correlating to the presence of a cancerous tumor in the body. The NIB is about the size of an aspirin and can detect VEGF at levels as low as 1 to 10 protein molecules in the billions of molecules present in 1 mL of body fluid. Products using NIB technology could ultimately become available over-the-counter to enable patients to measure biomarkers for cancer and other chronic illnesses. One can envision implantable sensors to track brain natriuretic peptide or troponin to enable instant therapy delivery for cardiovascular patients.

Tiny Implant Chip
Image taken from http://www.wired.co.uk/news/archive/2013-03/20/implantable-chip-doctor.

A multidisciplinary Swiss team has developed a tiny implantable chip that can test blood and wirelessly transmit the information to doctors.

Giovanni de Micheli and Sandro Carrara of École Polytechnique Fédérale de Lausanne (EPFL) invented the 14mm-long device. The device is a chip fitted with five sensors and a radio transmitter and is powered via inductive coupling with a battery patch worn outside the body delivering a tenth of a watt in energy. The chip is Bluetooth-equipped to transfer the data picked up by the chip’s radio signals.

The researchers’ goals are to use the chip to monitor five different molecules which may represent five different disease states. This proof-of-concept device has exciting implications for the field of personalized medicine; each person’s biological signals can be recorded and therapy tailored for each individual.

Tiny Resorbable Semiconductors: Smooth as Silk ‘Transient Electronics’ Dissolve in Body or Environment

Researchers from the University of Illinois at Urbana-Champaign recently developed silk-silicon implantable microcircuits that begin to dissolve two weeks after implantation.  These particular implantable devices were designed to produce heat to fight infection after surgery.  When the device were implanted in mice, they found that infection was reduced and only faint traces of the device remained after three weeks.  These transient implantable devices may have far-ranging applications not only in medicine but in reducing electronic waste.

Nokia has introduced a smart phone that can charge itself wirelessly. (http://www.nokia.com/global/products/lumia/)  It is safe to assume that Nokia uses induction based technology to charge the phone. The phone (equipped with a special receiver) is placed on a mat that generates an electromagnetic field. The phone’s special receiver uses this electromagnetic field to charge the phone’s battery. This technology can only power one device at a time and may generate heat during the charging process.

Recently, IDT and Intel partnered to announce the development of an integrated transmitter and receiver chipset for Intel’s wireless charging technology based on resonance technology. (IDT and Intel Partnership)  Magnetic resonance uses electrical components (a coil and a capacitor) to create magnetic resonance. This resonance can then transmit electricity to the receiver (device to be charged) from the transmitter (charging base). Magnetic resonance can power multiple devices at a time and may not generate excessive heat. A nice summary of this technology is available at Fujitsu Summary of Wireless Charging.

These technologies can be disruptive forces in the medical device industry that rely on battery depletion and replacement for subsequent sales (e.g., pacemakers, defibrillator, and noncardiac pulse generators). The device company that incorporates wireless charging into their devices may minimize replacement procedures for patients (and limiting procedural risk) while at the same time stabilizing their market position. Future device upgrades may be software upgrades and licensing that can be performed wirelessly without need for invasive procedure.

Researchers at the Fraunhofer Institute for Microelectronic Circuits and Systems IMS in Duisburg have developed an implantable biosensor that can measure glucose in sweat or tears obviating the need for needlesticks.  An electrochemical reaction using glucose oxidase that converts glucose into hydrogen peroxide; this concentration can be measured with a potentiostat and these measurements are used to calculate the glucose level. This biosensor has incorporated the entire diagnostic circuit into a fully implantable tiny sensor.  The biosensor can transmit the data via a wireless interface to a mobile receiver or even smart phone.

Biosensor Measures Glucose in Sweat and Tears

These researchers describe an amperometric sensor for the detection of ethanol in the extracellular fluid of animal brains.


Ethanol is one of the most widespread psychotropic agents in western society. While its psychoactive effects are mainly associated to GABAergic and glutamatergic systems, the positive reinforcing properties of ethanol are related to activation of mesolimbic dopaminergic pathways resulting in a release of dopamine in the nucleus accumbens. Given these neurobiological implications, the detection of ethanol in brain extracellular fluid (ECF) is of great importance. In this study we describe the development and characterization of an implantable biosensor for the amperometric detection of brain ethanol in real time. Ten different designs were characterized in vitro in terms of Michaelis–Menten kinetics (VMAX and KM), sensitivity (linear region slope, LOD and LOQ), and electroactive interference blocking. The same parameters were monitored in selected designs up to 28 days after fabrication in order to quantify their stability. Finally, the best performing biosensor design was selected for implantation in the nucleus accumbens and coupled with a previously-developed telemetric device for the real-time monitoring of ethanol in freely moving, untethered rats. Ethanol was then administered systemically to animals, either alone or in combination with ranitidine (an alcohol dehydrogenase inhibitor) while the biosensor signal was continuously recorded. The implanted biosensor, integrated in a low-cost telemetry system, was demonstrated to be a reliable device for the short-time monitoring of exogenous ethanol in brain ECF, and represents a new generation of analytical tools for studying ethanol toxicokinetics and the effect of drugs on brain ethanol levels.

Biosensors are now generating $13 billion in annual sales up from $5 million 30 years ago.  The combination of real-time biofeedback and the ability to deliver therapy has the promise to get us one step closer to a truly “personalized” approach to medicine.  Examples such as home glucose monitors and in-ear thermometers demonstrate that point of care biosensors can decentralize health care delivery.  Ultimately, the decentralization of health care will place patients once again at the forefront of their own care.