Joint project produces unique bacterial diagnosis application

STMicroelectronics and Mobidiag unveil a new technology that enables rapid bacterial diagnosis. The new lab-on-a-chip application allows a more accurate detection of infectious diseases that will lead to better treatment choices.

Early detection of systemic bacterial infections is essential for the successful management of antibiotic therapy and this technology aims to address the needs of laboratories that perform millions of blood cultures every year within target markets.

The application focuses on the DNA-based detection of sepsis-causing bacteria, using a diagnostic panel from Mobidiag that runs on ST's In-Check platform.

ST In-Check lab-on-chip platform works by amplifying clinically relevant DNA samples by Polymerase Chain Reaction (PCR) and has an integrated custom low-density microarray.

Microreactors within the micro-electro-mechanical-system (MEMS) chip carry the mixture of sample and reagents, while on-chip heating elements perform the temperature cycling.

Silicon's low thermal capacity and the In-Check design features claim to reduce reaction times and costs, compared with standard laboratory equipment.

The risks of cross-contamination inherent in conventional analysis methods are minimised, too, as the PCR and analysis is performed on chip in an encapsulated, self-contained unit.

The platform hosts a pathogen panel developed by Mobidiag to identify ten sepsis-causing bacterial species as well as methicillin-resistant strains of Staphylococcus aureus from positive blood culture samples.

The diagnostic panel has been designed to optimise the choice of antibiotic therapy in combination with results from Gram-staining, an empirical comparative method of differentiating bacterial species.

The results from the STMicroelectronics/Mobidiag solution will reduce the risks of antibiotic misuse and help physicians select the right treatment as early as possible.

"The combination of ST's semiconductor with Mobidiag's microbiological diagnostics opens new possibilities for effective detection and treatment of infectious diseases at the point of need," said Anton Hofmeister, group vice-president and general manager for ST's Microfluidic Division.

"We believe portable devices like the In-Check are set to make a difference in a growing number of diagnostic applications," he added.

After one year of joint development based on early prototypes, first units of In-Check lab-on-chips together with the control instruments are now shipping to Mobidiag for validation.

In addition, clinical trials are planned for early 2006, with the final product including validated controls, assay optimisation, and diagnostic reporting software to be launched later next year.