Sensors Central

What's New in Biosensors

Plenty of engineering work is inspired by nature, and some of it—biosensor development, for instance—actually incorporates biological components. In one example, the cities of New York and San Francisco have installed Intelligent Automation Corp.'s IAC 1090 Intelligent Aquatic BioMonitoring System, which uses fish to continuously monitor public water supplies for contamination and potential terrorism incidents. As the fish swim, breathe, and cough (yes, fish cough!) noncontact sensors monitor parameters such as ventilation and cough rates. Should the fish detect toxic conditions, the IAC 1090 takes a series of water samples and notifies staff. According to IAC, "Chemical concentrations can be measured with an instrument, but only biosensors (fish) can be used to measure toxicity that is potentially harmful to humans." (

Microscale Developments

Chitosan, a structural element found in the exoskeletons of Chesapeake Bay blue crabs, is key to a system that University of Maryland researchers are developing. The researchers use it to coat miniature vibrating cantilevers within a MEMS device. Different cantilevers can detect different substances, and when even a tiny amount of a targeted substance enters the device from the air or water, the chitosan reacts, changing the vibration on the corresponding cantilever. An optical sensing system detects the change and signals the presence of the substance. (

NanoSensors Inc. is evaluating a generic biosensor design that will accommodate a sensor on a chip. According to CEO Dr. Ted Wong, "The company believes in the value of using porous silicon as a sensor substrate to vastly improve the sensitivity for the detection of targeted agents, and now with the [Michigan State University] license, the company will be able to build its first sensors using this platform." Wong is referring to NanoSensors' agreement with MSU that gives it exclusive worldwide rights to use patent-pending electrochemical DNA biosensors for detecting certain bacteria in commercial applications. (,

Luminex Corp. has received a $300,000 DARPA research grant that focuses on developing the company's xMAP chip-scale technology for biodefense applications. The concept leverages xMAP—a bead-based flow cytometry solution for multiplexing biological assays—to detect biopathogens on the scale of a microchip. (

Changes in Temperature Sensor Use

A new research study by Flow Research finds several important shifts occurring in the temperature sensor market. The study, "The Market for Temperature Sensors in the Americas," 2nd Edition, says one important technology change is a transition from contact to noncontact temperature measurement. This involves a shift away from thermocouples, RTDs, and thermistors (all contact sensors) to IR thermometers and fiber-optic temperature sensors (both noncontact). In addition, there is a broader shift away from thermocouples, which typically are less accurate and less stable than RTDs and thermistors. (

Paros Wins Award for Sensor Technology

Jerome M. "Jerry" Paros, president and chairman of Paroscientific, has won ISA's Albert F. Sperry Founder Award for developing quartz crystal resonator sensor technology. Quartz crystal resonator sensors—technology first introduced by Paros in 1972—can help detecting tsunamis and other complex geophysical phenomena. (

Provision Improvements

Power generation has made intriguing progress recently. Photonic Power Business Unit of JDSU says it has achieved a world record: its 3 V and 5 V gallium arsenide photovoltaic power converter produces optical-to-electrical conversion efficiency >50%, near the maximum theoretical limit. Photonic power cost-effectively drives electronic devices operating in high-voltage, RF/EMI, and magnetic fields, where traditional copper options are complex or impractical. The improvement brings competitive advantages to industrial sensor, wireless communications, and medical applications, the company says. (

Roy Freeland, CEO of the U.K. company Perpetuum, says of his company's new vibration energy harvester, "No competitive offering has come close . . . in terms of the amount of data that can be sent or the conditions under which it will operate reliably."

The PMG7 microgenerator, available to OEMs and end users, converts kinetic energy from the vibration of equipment running at mains frequency (50 or 60 Hz) into electrical energy. It can generate up to 5 mW, which is enough to power a wireless transmitter sending 6 KB of data every few minutes, or small amounts of data, such as temperature readings, several times a second. It installs easily and can operate in most industrial environments and at minimal vibration levels (25 mg). (

Battery Developments

Several new battery technologies are in the R&D stage. Oak Ridge Micro-Energy, for instance, has developed a new rechargeable thin-film lithiumion battery that can operate at high temperatures. Based on a new anode-cathode combination, the company's prototypes were cycled at a record high of 170°C (338° F). Compare that to the conventional rechargeable lithiumion batteries that can cycle at about 60°C maximum. According to Mark Meriwether, president and CEO, this could open up new markets in areas such as sensors for downhole and other harsh environments, and semiconductor diagnostic wafers. (

 Oak Ridge Micro-Energy's rechargeable thin-film battery
Oak Ridge Micro-Energy's rechargeable thin-film battery

Rutgers University has granted mPhase Technologies the right to test its lithium-based alternative chemistries for a prototype nano-structured battery, which Rutgers says "promises to significantly change the storage battery industry."

In another announcement, mPhase reported that the microscopic structure designs of its prototype battery and magnetometer survived a high acceleration test at 12,000 g, conducted at Picatinny Arsenal, the Army's foremost munitions research facility. The test paves the way for developing small guided munitions. (,

Military—And More

In many of military scenarios, battery maintenance is undesirable or impossible. So Neah Power Systems Inc. is working to extend its patented fuel-cell technology, based on porous silicon electrodes, to power sensors for military, portable electronics, and homeland security applications. "Most fuel cells require air to react with the methanol fuel to produce electricity," said chairman Dan Rosen, PhD. "Neah uses liquid electrolytes that enable them to be configured to either use air or run as a closed system in applications where you don't want your sensor and its fuel cell to be detected." (

And finally, MTI MicroFuel Cells Inc. (MTI Micro) says it has achieved an energy density of more than 1.3 Wh/cc of fuel on a 30 W laboratory test unit—which represents a >30% increase in fuel efficiency. For high-power applications, MTI Micro's direct methanol fuel cell (DMFC) system, Mobion-30, is being designed to produce up to 30 W of continuous power in a portable, lightweight, energy-rich power-pack, allowing deployed soldiers to use portable electronic devices for much longer periods of time. For low-power military applications, MTI Micro's Mobion-1 is designed to produce 1 W of continuous power. (

Concept model of MTI Micro's Mobion-30 system
Concept model of MTI Micro's Mobion-30 system