Professor Hywel Morgan at the University's School of Electronics & Computer Science (ECS) and Dr Peter Roach at the School of Chemistry and their team have received a European grant (€450k) to create a system that can detect single molecules in biological solutions.
They are using variants of molecules found in biology and creating 'senses' from electrical charges caused by the binding of the molecules to mimic the human nose. With this approach, the sensitivity of the device can be a thousand times better than the currently available electronic nose.
The receptors, which will be housed within an artificial membrane, remain in a closed steady state until approached by smell molecules, when they will open and transmit an electrical signal which will indicate the nature of the odour.
Professor Morgan comments: "Many medical diseases involve odour. A device such as ours could measure different hormones, diagnose diseases and even sniff for traces of explosives. Most odours are still mapped by humans. If we can find a way to replace this function with technology, we could use odour detection in many new areas."
Scientists are developing the world's smallest, high-performance and low-power sensor in silicon which will have applications in biosensing and environmental.
Sunday, August 3, 2008
Bioelectronic DNA detection involves forming an electronic circuit mediated by nucleic acid hybridization and it serves as the basis for a DNA detection system called eSensor™ [1-4]. This system uses low-density DNA chips containing electrodes coated with DNA capture probes. Target DNA present in the sample hybridizes specifically both to capture probes and ferrocene labeled signal probes in solution thereby generating an electric current. Currente Sensor DNA chips contain as many as 36 electrodes for simultaneous detection of multiple pathogens from a single sample.
Many pathogens cause both acute and chronic disease at relatively low copy number and may be difficult or impossible to propagate in culture. Thus, most pathogen detection systems rely on nucleic acid amplification by using polymerase chain reaction (PCR). One highly effective amplification strategy targets conserved sequences among the family of organisms of interest. Such broad-range PCR strategies have been used to identify and characterize several known and previously uncharacterized bacteria [5,6] and viruses [7,8]. In order to maximize the utility of these effective pathogen nucleic acid amplification systems, amplification needs to be coupled with rapid, sensitive, and specific detection. Bioelectronic DNA detection by use of the eSensor chip might fulfill this need.
Human papillomaviruses (HPV) serve as an ideal model system for determining the efficiency and feasibility of eSensor DNA detection technology since there are at least 30 distinct genital HPV types that can be effectively amplified with broad-range consensus PCR primers. We designed two eSensor chips, each containing 14 probes specific for the conserved L1 region of the HPV genome. We evaluated clinical cervical cytology samples known to contain one or more HPV types. The eSensor DNA detection platform successfully detected the correct HPV type in most of these clinical samples, demonstrating that the system provides a rapid, sensitive, specific, and economical approach for multiple-pathogen detection and identification from a single sample.Background We used human papillomaviruses (HPV) as a model system to evaluate the utility of a nucleic acid, hybridization-based bioelectronic DNA detection platform (eSensor) in identifying multiple pathogens.