MEMS for biomedical can do far more than simply "sense"
June 15, 2011 // Bill Schweber
Most engineers think of MEMS devices primarily as sensors. This makes sense, because that's where the bulk of the market is, as airbag triggers in cars, pressure sensors, accelerometers, or gyroscopes. But there are many other attractive applications for MEMS technology, as I learned in a conversation with Dr. Jeffrey T. Borenstein, Distinguished Member of the Technical Staff and Director of the Biomedical Engineering Center at Draper Laboratory (Cambridge, MA), while at the TechConnect World Conference & Expo in Boston.
For biomedical applications, Draper and others are investigating MEMS technology as a critical enabling technology for many non-sensor situations, including large-device fabrication as well as tiny, sophisticated actuators.
For example, in one project, a silicon wafer is micro-etched with tiny channels to act as a fabrication master. This master is then used to make many "copies", which are then stacked up as layers. The result is an artificial organ to be used as a supplement or even a replacement for the liver, as the blood flows through the many channels. This is clearly much better for dialysis patients, who now must go in to a clinic for blood cleaning three times a week, typically.
Critical note for those who assume that "smaller is better" when it comes to process geometries, and think that dimensions in the tens of nanometers are the needed--similar to those of today's digital ICs — keep this in mind: Dr. Borenstein said that the appropriate biomedical-device features are on the order of ten microns, which is three orders of magnitude larger than our state-of-the-art ICs, since blood cells are around 5 microns in diameter.
There are also interesting developments under way for applications in precision, internal medicine delivery using MEMS-based actuators. Presently, a drug must be delivered either by injection, or orally, and thus often causes unavoidable collateral damage to other parts of the body besides the target area. Also, the patient may have problems adhering to the delivery schedule and protocol. Even so, the medicine may not reach the right spot, in the right dose, or with the right timing.
For example, there's some indication that it may be possible, with the right medicine to spur regeneration of the frequency-tuned hair cells in the inner ear which respond to sound (vibration) and are critical to converting the incoming sound energy to nerve signals. Dr. Borenstein said they are exploring doing this via a MEMS-based, microfluidic reciprocating push-pull pump which periodically squirts the dose into the inner-ear area. The thinking is that such a burst-type injection is preferable to a slow, continuous application, since it is less intrusive and thus less prone to rejection, where the bodies proteins attack the injection as a foreign material.
Don’t expect to see this system too soon — problems are not just physiological. While there are options for powering such a device, including batteries and wireless recharging, the refilling of the implanted drug container is another challenge. Draper is working with Massachusetts Eye and Ear Infirmary, a leading institution, to test the concepts, but it will be several years before they have preliminary test data. That's certainly a big difference from your conventional new-product cycle for most electronics we design.
(For additional information, see here, here, and here.)
Bosch suggests cars to coast for fuel efficiency
December 11, 2013
With a package of relatively simple but coordinated measures, cars can raise their fuel efficiency. Automotive supplier Bosch ...
Europe is giving up on leading edge digital chip design
Design-free RF-based wireless charging redefines user experience
Electromobility, Formula One and the Fatal Consequences of Bad Software Design: The top ten stories of 2013
Brushless DC servo motors integrate field-oriented closed-loop servo control
How green is your code?
December 11, 2013
Mid-November, French technology cluster Images & Réseaux was holding a one-day presentation of start-up companies at Rennes’ ...
Chinese LED lighting market to more than double to $7.4 billion in 2017, forecasts Lux Research
80V Wide Range I2C Power Monitor Simplifies Challenging System
CUI launches complete range of free 3D power supply models to speed power supply design
- 3mm × 3mm QFN IC Directly Monitors 0V to 80V Supplies
- UltraCMOS® Semiconductor Technology Platforms: A Rapid Advancement of Process & Manufacturing
- Adaptive Cell Converter Topology Enables Constant Efficiency in PFC Applications
- Isolated 4-Channel, Thermocouple/RTD Temperature Measurement System with 0.5°C Accuracy
InterviewPerformance monitoring solution helps provide intelligent control of high power systems
A performance monitoring solution designed to enable companies to monitor high power IGBT module systems in locomotive, wind turbine, High Voltage DC and industrial drive applications was unveiled this ...
Filter WizardCheck out the Filter Wizard Series of articles by Filter Guru Kendall Castor-Perry which provide invaluable practical Analog Design guidelines.
Linear video channel
READER OFFERRead more
Internet of Things (IoT) manufacturer Ciseco has launched the Raspberry Pi ‘Wireless Inventors Kit’ (RasWIK), featuring 88 pieces to provide everything a Pi owner needs to follow a series of step-by-step projects or to create their own wireless devices, without the need for configuration or even writing code.
RasWIK has been designed to be highly accessible, demystifying the dark art of wireless and enabling anyone with basic computing skills to begin building wireless devices with a Raspberry Pi. You can create anything from a simple traffic light, to a battery monitor, or even a temperature gauge that sends data to the Xively IoT cloud so billions can access the data.This month, Ciseco is giving away twelve Raspberry Pi Wireless Inventors kits, worth £49.99 each for EETimes Europe's readers to win.
And the winners are...
In our previous reader offer, Farsens was giving away five kits for EEtimes Europe readers to evaluate its FenixVortex, Kineo and X1 wireless, battery free sensor tags.
Lucky winners include Mr A. Neil from the UK, Mr. E. Delvaux from Belgium, Mr Lengal from the Czech Republic, Mr H. Bijlsma from the Netherlands, and Mr G. Pfaff from Germany. All should be receiving their packages soon. Lets wish them some interesting findings with their projects.
December 15, 2011 | Texas instruments | 222901974
Unique Ser/Des technology supports encrypted video and audio content with full duplex bi-directional control channel over a single wire interface.