The EU-funded 'Integrated and functional lab-on-chip' (INFULOC) project has pioneered a fully integrated LOC with a high level of functionality. Applications focused on both environmental and medical areas. Exceptional integration on the chip was achieved through the incorporation of microvalves. This allows for sophisticated processing of the fluids under test. The system can use sensitive optical detection of intracellular green fluorescent protein. For even more demanding fluidic control, the researchers constructed a 24-cell culturing array. The set-up tested toxicity of pyocyanine on a human breast cancer cell line (Michigan Cancer Foundation-7 (MCF-7). Moreover, it could indicate liver damage in human hepatocyte carcinoma liver cells. Other uses included monitoring the sequential combination of effects of a chemotherapy agent, paclitaxel and aspirin on MCF-7 breast cancer cells. To increase absorption sensitivity, the scientists used novel optical broadband cavity enhanced absorption spectrometry (BBCEAS). This system uses high reflectivity mirrors enabling use of a low cost light emitting diode. Integration of BBCEAS within the LOC resulted in a 35-fold increase in sensitivity for the osteocalcin test, a marker for osteoporosis. Environmental concerns prompted the scientists to use laser micromachining so a boron doped diamond can be used instead of mercury electrodes. The system can detect lead in tap water and heavy metals in river water. Application areas are very wide and also include detection of protein misfolding, especially important in ageing and finding bacteria in blood transfusions. The LOC device is easy-to-use, ecologically sound and has a strong possibility of commercialisation.
Lab-on-chip, environment, medical, microvalve, cell culturing array, toxicity, laser micromachining, protein misfolding