Scientists at the University of Minnesota have successfully developed and tested a prototype of Z-Lab, a portable diagnostic platform designed to perform on site testing of biological samples for various ailments. This is the first version of the prototype developed for point-of-care diagnostics. The details of the device and results of the test are reported in the paper “Portable GMR Handheld Platform for the Detection of Influenza A Virus” published recently in ACS Sensors.
The prototype was used to test for the presence of the influenza A virus (IAV) in a treated sample. The testing process, which parallels the commonly used ELISA test process, involves antibodies acting as sensors capturing a biomarker, to which a detectable object is added that will bind to the sensor-biomarker complex. In the case of Z-Lab, a GMR (Giant Magnetoresistance) chip is used as the surface, and a magnetic label (MNP) is the detectable object. If the disease indicator is present in the sample, magnetic tags will bind to the GMR sensor resulting in a change in the electrical signal. The signal is monitored by the Z-Lab handheld device which is capable of data processing, display, wireless communication, and GPS location services depending on the needs of the specific application.
Z-Lab can be operational with minimal equipment. All it needs are a smartphone or similar device with a program that can receive, interpret, and display test results, and an adapter to charge the battery. The size of the Z-Lab (about the size of a large cellphone) makes it highly portable, allowing the device to be easily moved around and used in multiple settings. These features make it an accessible testing device that can be used in typical healthcare settings such as clinics, hospitals, and labs, as well as in homes. Test results can be transmitted wirelessly from Z-Lab to a secure application on a computer, smartphone or other mobile device. Lead scientist on the project and ECE faculty, Prof. Jian-Ping Wang (who is also Robert F. Hartmann Chair, and director of C-SPIN) says,
“The high sensitivity of this device allows it to detect various ailments—including infections, heart disease and even cancer—faster, easier and earlier than ever before. We see this as a preventative device that will ultimately save lives.”
The GMR chips used in this system give it multiplex capability, which can significantly reduce costs associated with multiple laboratory tests. Z-Lab can also potentially reduce costs associated with sending samples to labs, handling them safely, and skilled technicians to test them. Currently the device has successfully tested prepared samples, i.e. fluid samples that were treated and washed to isolate the virus.
The project scientists plan to develop Z-Lab’s capability to handle and diagnose unprocessed biological samples on-site which will be critical to the use of the device in non-lab or field settings. Looking forward, the team will continue testing and working on enhancements to Z-Lab to study its effectiveness with testing untreated samples using a proposed microfluidic device (to be integrated within Z-Lab) that can treat and prepare the sample. The assay will also have to undergo further evaluation to study its effectiveness in the case of biological samples. According to Prof. Andres M. Perez, who is on the faculty of the Department of Veterinary Population Medicine (and also lead scientist, and Director of CAHFS),
“Z-Lab’ s ability to inexpensively test for multiple biomarkers at once, along with its ability to automatically send nonprivate information to databases, will enable scientists to identify new correlations and new lines of research.”
The goal is to offer affordable, and accurate tests to patients in practically any setting, be it at the doctor’s office or in their own homes, which is especially critical for individuals suffering from chronic conditions affecting their mobility. The device also holds promise for use in conducting tests on animals making it far more affordable than having to transport the samples to labs.
In addition to the two lead scientists, postdoctoral scholars Dr. Kai Wu, Dr. Venkatramana D. Krishna, and former student Todd Klein, (they contributed equally to the work), and graduate student Diqing Su, are the other authors of the paper.
The authors acknowledge XPRIZE Foundation and Nokia Sensing XCHALLENGE competition for motivating the design of the Z-Lab Diagnosis Platform which won Distinguished Prize Award. Prof. Jian-Ping Wang has equity and royalty interests in, and serves on the Board of Directors and the Scientific Advisory Board, for Zepto Life Technology LLC, a company involved in the commercialization of GMR Biosensing technology. The University of Minnesota also has equity and royalty interests in Zepto Life Tech LLC. These interests have been reviewed and managed by the University of Minnesota in accordance with its Conflict of Interest policies.
*Photo credit: Dr. Kai Wu (one of the paper authors)