Novel sensors for hazardous substances
Analysis of biological samples for rapid detection of disease markers can save lives and reduce healthcare costs as well as help the pharmaceutical industry to bring new drugs to market more quickly. The greater the sensitivity and specificity using ever-smaller samples, the higher the efficiency and the lower the cost. European researchers sought to develop novel biosensors capable of detecting negligible concentrations of biomarkers in minute liquid samples. Target sample volumes were a nanolitre (nL), or a billionth of a litre, and a picolitre (pL), or a trillionth of a litre. EU-funding of the Ganano project enabled production of the first-ever biosensor device based on gallium nitride (GaN). The sensor was essentially a modified transistor whose surface voltage changed (inducing a change in measured current) in response to contact with samples of changing electrical composition (e.g. dipoles, polar liquids, ion flow, cellular activity). Modifications to the basic design by attaching large molecules to the surface enabled detection of specific ions. In addition, technology for fast pipetting of nL volumes was developed and applications to a variety of water quality testing scenarios are being pursued by consortium members. Smaller, less expensive portable versions of the Ganano system were employed successfully for water quality assessment in aircraft, a process that conventionally is time consuming and quite complicated. Promising preliminary results were obtained for extremely sensitive detection of nitrogen oxides (NOx), a family of gases linked to explosives and many pollutants. Ganano technology should drastically reduce costs related to sensing of hazardous substances and disease markers while enhancing human health and safety.
