Fraunhofer Researchers Demonstrating Scalable, Digitized PCR Test System at MEDICA

PCR methods are considered the diagnostic gold standard for detecting a coronavirus infection. Unlike rapid antigen tests, they work even with a small amount of virus and identify the pathogen with a high level of accuracy. The disadvantage: Standard PCR tests are currently not suitable for mass, event-related testing on site, which requires a quick result at acceptable costs with the simplest handling. Fraunhofer researchers, however, are currently developing a scalable, open and digitized PCR test system that would provide results in 15 minutes. The researchers are showcasing the structurally compact system this week at CompaMed in Düsseldorf, Germany.  
 
To be better prepared for future pandemics, immediate tests are required that detect infections in a highly sensitive manner and as clearly as possible in a few minutes and transmit the results immediately and digitally to decision-makers and clinicians. The Fraunhofer Institutes for Microtechnology and Microsystems IMM and for Experimental Software Engineering IESE are researching such a rapid test system in the OPEN-POCT project. It aims to combine the advantages of the more sensitive PCR tests and the cheaper, but less reliable, point-of-care antigen tests sold in drugstores and supermarkets, while being less expensive than the rapid PoC (point of care) PCR test systems currently on the market. 

Fraunhofer IESE focuses on the areas of data transmission, data security and data sovereignty, while Fraunhofer IMM, as the project coordinator, is responsible for the hardware and the integration of suitable detection reactions. The project is funded by the state of Rhineland-Palatinate as part of the European Regional Development Fund (ERDF REACT-EU). Fraunhofer IESE focuses on the areas of data transmission, data security and data sovereignty, while Fraunhofer IMM, as the project coordinator, is responsible for the hardware and the integration of suitable detection reactions. The project is funded by the state of Rhineland-Palatinate as part of the European Regional Development Fund (ERDF REACT-EU). Fraunhofer IESE focuses on the areas of data transmission, data security and data sovereignty, while Fraunhofer IMM, as the project coordinator, is responsible for the hardware and the integration of suitable detection reactions. The project is funded by the state of Rhineland-Palatinate as part of the European Regional Development Fund (ERDF REACT-EU).
 
“The use of PoC-PCR systems to contain or even prevent a pandemic is currently ruled out, since the test sets are available in large numbers and immediately everywhere and should also enable inexpensive mass tests, for example in test centers at the airport. Questioning this apparent dogma is the goal of the OPEN-POCT project. Only a sensitive alternative to the PCR test in the laboratory that can be used anywhere and is quickly available will make it possible to effectively interrupt chains of infection in the event of an outbreak, and thus really contain a pandemic at an early stage, before the global movement of people makes this impossible,” said Dr. Christian Freese, a Fraunhofer IMM scientist.
 
Transfer PCR From the Lab to a Rapid Test System
Inexpensive antigen tests that can be produced in large quantities are not immediately available when new pandemic infectious diseases break out and require too long a development time to contain or even prevent a pandemic. Current PoC-PCR tests, on the other hand, are up to 30 times more expensive than antigen tests. Among other things, low production volumes, high investment costs and logistical effort as well as complex microfluidic structures drive up prices. They are ,therefore, unsuitable for mass testing and use at the point of care.

“We want to transfer the PCR from the laboratory to a rapid test system that can be used in large numbers on site. Therefore we design our solution as an open system, to enable many manufacturers to produce components such as cartridges or reagents,” a Fraunhofer researcher said. “In principle, it is about setting up an administrative and regulatory ecosystem for a scalable, open and digitized PoC-PCR test system for the detection of pandemic pathogens. The price for a test per person should be in the lower single-digit euro range.”

Achieving Quicker Test Results
The researchers also want to shorten the PCR process duration. “A PCR test—at the airport, for example—should only take a few minutes,” said Freese. The methodology of the PCR requires two temperatures. The reagents with the sample liquid have to be heated and cooled, which is very time-consuming. The heating block integrated in the PCR devices is first heated to over 90 degrees so that the DNA strands can be separated. It is then cooled to around 60 degrees. Now the genetic material of the virus is multiplied: one strand of DNA becomes two, in the next step two become four strands and so on. This is how the virus becomes detectable. To avoid the tedious process of constant heating and cooling, Freese and his team use two different heating zones—a hot and a cooler chamber—between which the sample liquid is pumped back and forth using a pump in the cartridge. The liquid moves from one heating zone to another in the detection cartridge through loop-like microfluidic channels. In doing so, it is stretched and thus offers a large surface-to-volume ratio and consequently rapid heat transport. 

“As a result, we quickly reach the target temperature required for the PCR, and there is no need to constantly regulate the heating block to two temperatures,” explained Freese. In their preliminary tests with purified viral RNA, the researchers were significantly faster than standard PCR laboratory tests: the result was available after just 15 minutes with comparable sensitivity.
 
The device, which measures 15 by 15 by 20 centimeters, has a simple design: in addition to the microfluidic cartridge and pump, it includes heating structures and a fluorescence camera as a detector; expensive components are not required. Freese also sees the rapid adaptation of the OPEN POCT platform for the detection of other viruses as an advantage. “PCR tests can be quickly adapted to any pathogen, the genetic information of SARS-CoV-2 was decoded quickly,” he noted. 
 
Reducing Bureaucracy Through Digital Data Transfer
The OPEN POCT platform is supplemented by the integration of a digitized, automated transmission of positive test results directly to the health authorities. In order to quickly contain a pandemic, not only technological hurdles but also bureaucratic obstacles must be removed. This is only possible if the automated data transfer via secure data systems is linked to the data protection of individuals, general IT security and data security. An expansion of digital data transfer solutions, such as linking to the Corona Warn app, is planned. The project partners also offer decision-makers a comprehensive white paper that takes into account not only diagnostic and data protection aspects but also regulatory issues.

Fraunhoder researchers will be demonstrating the system through Nov. 17 in Hall 8a, Stand G10.