German Electronics Giant Siemens Enters DNA Diagnostics Fray with Plastic Strip Array System

Motorola and Nanogen will soon have a European competitor in the DNA diagnostics marketplace: Siemens Medical Systems, a division of German electronics giant Siemens, is teaming up with November, a startup based in Erlangen, Germany, to develop a tabletop DNA diagnostic system.

While Motorola and Nanogen offer chip-based DNA diagnostics with sophisticated surface architectures, Siemens will be using plastic strips. Up to 20 different oligonucleotide capture probes will be bound to each strip, compared to 100 in Nanogen’s NanoChips and 36 in Motorola’s eSensor chips.

Perhaps the most significant difference, however, between the Siemens-November device and the Motorola and Nanogen platforms, is that the Siemens-November device will integrate all sample-handling steps, including amplification of the DNA, and will not require DNA labeling. “We are going to offer an integrated kit with a cartridge where you can do almost all the steps from the biological sample to the diagnostic result,” said Joerg Hassmann, head of the electrohybridization team at November.

But both Nanogen and Motorola are working on similar solutions: Before the end of 2002, Nanogen wants to introduce an amplification step directly at a site on the chip, using strand displacement amplification (SDA). Motorola is developing a system “which will incorporate microfluidics to achieve integration of sample prep, amplification, and detection into a disposable cartridge,” said Mindi Bui, a company spokeswoman, in an e-mail.

The Siemens technology will be inexpensive and able to compete with standard immunological assays, according to Hassmann. The instrument will probably be closer in cost to an eSensor, which is $5,000 for the 12-sample model and $25,000 for the 48-sample model, than to a NanoChip workstation, which has a list price of $160,000. The price for each test strip will be “a low double-digit number,” Hassmann said, which is similar to CMS’s eSensor chips and well below Nanogen’s.

The approach that Siemens and November are taking to hybridization detection also differs from Nanogen’s NanoChip platform. The NanoChip platform uses electrochemical methods to program the chip and enrich DNA from the sample, and then uses optical detection. This allows users to individually program the sites. “We can use one site at a time,” said Kieran Gallahue, Nanogen’s president. “Ours is truly like a book of matches, and each match you can burn individually, or you can burn them in a group,” he said.

“We do it exactly the other way around,” said Hassman. “We hybridize and then detect using electrochemical methods,” which is more similar to Motorola’s approach.

This is the first DNA diagnostic venture for Siemens Medical Solutions, but the company is no newcomer to diagnostics. For the last two years, the division has also been developing a protein diagnostic system with Pes Diagnosesysteme in Leipzig, Germany, which is expected to reach market by the end of 2002.

Siemens has been making diagnostic equipment for years, especially hospital radiology instruments, but felt it had to expand its product range, according to Emil Wirsz, Siemens Medical Solution’s director of new business development biotechnology. The company is currently “massively looking into expanding the team” for its biotechnology efforts, he said, and is planning to get into molecular imaging.

The Siemens-November platform will have applications in routine diagnostics, including identification and characterization of pathogens from samples of blood, urine, or saliva, profiling tumors; and detecting genetic polymorphisms, Siemens said. November, which hopes the technology will be ready for licensing and clinical validation by 2003, will develop the biochemical and electrochemical detection methods, while Siemens will be responsible for the device itself.

The system will be marketed to clinical laboratories first but will be aimed at point-of-care diagnostics later, the company said.

While this is exactly the target market that Nanogen and Motorola are aiming to reach, both believe they have a key advantage over Siemens. “We are on the market today, we are not a concept, we are a product,” said Gallahue.

— JK