Smart Glass Lab on chip devices integrating electronics and nanosensors – LabInGlass

Microfluidics which consists in handling fluids on a chip is a young emerging field that is revolutionizing several scientific research fields at the interface with life sciences. Handling on chip small quantities of biological liquid becomes possible while working in a parallel way with multiple parameters opens new routes for both proteomic and genomic applications. The fast recent development of such microfluidic devices that integrate all the stages of analysis on a few square centimeters is today becoming a reality for many applications. Such devices are called "Labs-onchip".

It is of importance to note that the world market of biochips has largely increased these last years passing from 1.64 billion dollars in 2006 to more than 2.11 billion dollars in 2008. This market growth is predicted to increase continuously at a rate of 12.7% to reach 3.84 billion dollars in 2013. This market is segmented today in three major categories : ADN microarrays (1.6 billion dollars in 2013), proteins microarrays (600 million dollars in 2013) and Labs-on-chip (1.2 billion dollars in 2013). The good financial health of this sector is based on the fact that many applications are concerned from the medical diagnosis, the personalized therapy, toxicology, the medical and environmental risks (biological and chimical threats) to extreme chemistry. These markets reflect a need growing for societal stakes related on aging of the population, cancers, degenerative nervous diseases, cardiovascular diseases, autoimmune diseases… Many applications exist such as early diagnosis of pathology, “patch” for under cutaneous controlled delivery of active ingredients over a long duration, salivary test for the detection of narcotic catch, controls in real time of pathogenic agent, food quality control on the chain of production. Many opportunities can also emerge due to the youth of the market of the biochips.

To our knowledge, only few studies on the integration of optical or electric sensors in such miniaturized devices for analysis exist. The current market of microfluidic foundry breaks up into two great families of chips: 1/ the polymer chips that are generally limited to soft conditions (ex: soft chemical solutions with neutral pH, without solvent, low temperatures and weak electrophoresis field) i.e. noncorrosive with respect to polymer, 2/ glass chips sealed at very high temperature (near glass transition temperature between 800°C and 1000°C) which inhibits integration of electrodes or nanostructures. Before our patent, only one method of sealing based on anodic bonding (patent P.Renaud EPFL), allowed to reduce down to 400°C the sealing temperature. However such anodic bonded device that is based on intermediate layer of amorphous Silicon cannot be used for electrophoresis under high electric field. We will show here the limits of these anodic bonded chips which age very badly during electrophoresis of a saline solution. The main goal of this project consists in developing our recent patent (CNRS patent N° FR 10 54183 deposited 2010/05/28) which enables low temperature bonding of true glass microfluidic chips. The low temperature of sealing makes possible the integration of sensors even fragile in the glass device, which opens an unexplored field for smart portable Labs-on-chip that could integrate both sensors and electronics.