Tiny Turns Powerful
Xia's nanofluidic expertise and advanced terahertz spectroscopy could enable on-the-spot diagnosis of cancer and other diseases, leading to faster and improved treatments.
Xia (top left), director of the UMass Amherst Nanodevices and Integrated Systems Lab, employs high precision methodologies in order to engineer increasingly small components. Much of his work is done in the Nanotechnology Cleanroom Lab, which is an enclosed “clean” facility. Within its walls the concentration of airborne particles are controlled to specified limits, and researchers must wear full-body suits to enter. Affiliated with the Center for Personalized Health Monitoring—one of the three new centers in the Institute for Applied Life Sciences—Xia is using this methodology to help create small devices with unprecedented capability for medical analysis.
Xia is conducting research that will allow personal health monitoring devices to be more compact and more powerful. As data is continuously collected from personal health monitors, how to effectively store the gigantic amounts of data is a critical issue that impacts the design of the monitors. To meet this challenge, Xia is developing a new memory technology called the “resistance switch” or “memristor.” Compared with traditional data storage devices such as hard drive and CMOS (complementary metal-oxide-semiconductors) based memories, this device is smaller, faster, and more power efficient.
“In our lab we try to develop better devices,” Xia says. “We also want to develop better fabrication techniques which can make them smaller and cheaper. And we want to study device physics because in order to make a better device you need to better understand the device.”
Working with collaborators in the campus’ Terahertz Lab (directed by electrical and computer engineer Sigfrid Yngvesson) and at the UMass Medical School, Xia is also developing a device that can rapidly scan for an array of biomolecules using only one drop of liquid—blood, saliva or other biological fluids. The one-drop device could provide on-the-spot cancer detection, glucose testing, or iron counts. By exposing the fluid to high-frequency signals such as those in the terahertz range, the device will be able to detect various types of molecules, as each biomolecule gives off a unique responsive signal. The nanofluidic channels that Xia and his team are developing will allow for transport of the tiny biological molecules.
“The beauty [of collaboration] is if you can combine different expertise in different areas and work towards the same goal, the result is going to be more powerful than working alone,” Xia says.
Xia, an expert in engineering extremely small channels, is fine-tuning his nanofabrication technique to allow them to be even narrower. The DNA molecules—the molecules these devices will be testing—are small and complex. DNA in a free space, Xia explains, curls up like a ball of yarn, making it difficult to analyze. In a confined space, however, it stretches out, making it easier to test. Once developed, these tiny channels will be laid over the terahertz circuit.
“If you can integrate those channels with the circuit, that’s going to make you a very powerful nanofluidic tool,” Xia says.
Xia’s research is making huge strides towards the proverbial lab on a chip. His patented non-volatile technology allows for universal data storage, so that each unit is more densely packed with memory capacity and information can be stored to the device without a constant power source. His nanofluidic expertise and advanced terahertz spectroscopy could enable on-the-spot diagnosis of cancer and other diseases, leading to faster and improved treatments. With these features combined, patients may soon be able to take potentially life saving measurements continuously throughout the day—a task that currently requires a trip to the doctor and weeks of time waiting for results.