ABSTRACT
A novel integrated bio-sensor technology based on thin-film bulk acoustic wave resonators on silicon is presented and the feasibility of detecting DNA and protein molecules proofed. The detection principle of these sensors is label-free and relies on a resonance frequency shift caused by mass loading of an acoustic resonator, a principle very well known from quartz crystal micro balances. Integrated ZnO bulk acoustic wave resonators with resonance frequencies around 2 GHz have been fabricated, employing an acoustic mirror for isolation from the silicon substrate. DNA oligos have been thiol-coupled to the gold electrode by on-wafer dispensing. In a further step, samples have either been hybridised or alternatively a protein has been coupled to the receptor. The measurement results show the new bio-sensor being capable of both, detecting proteins as well as the DNA hybridisation without using a label. Due to the substantially higher oscillation frequency, these sensors already show much higher sensitivity and resolution comparable to quartz crystal micro balances. The potential for these sensors and sensors arrays as well as technological challenges will be discussed in detail.
Subject(s)
Biosensing Techniques/instrumentation , DNA/analysis , Electrochemistry/instrumentation , In Situ Hybridization/instrumentation , Protein Array Analysis/instrumentation , Proteins/analysis , Biosensing Techniques/methods , Coated Materials, Biocompatible/chemical synthesis , Coated Materials, Biocompatible/chemistry , Electrodes , Equipment Design , Equipment Failure Analysis , Feasibility Studies , Gravitation , In Situ Hybridization/methods , Pilot Projects , Protein Array Analysis/methods , Reproducibility of Results , Sensitivity and Specificity , Staining and Labeling , Streptavidin/analysis , Stress, Mechanical , Systems IntegrationABSTRACT
Disasters are often tragic outcomes of high-risk technologies such as mines. In Australia, more mines are being developed every day, and the risk of disasters is ever increasing. No matter how effective our conventional safety devices are, there is a form of accident that is inevitable. This relates to accidents that result from 'interacting failures' in a way that could not be foreseen by the designers. Before the question: Are we really controlling the risk? This is one of the fundamental questions that will be addressed in this paper: Do we have the ability within the Mining Industry and other industries to effectively prevent these catastrophes, or are we, on the contrary, faced with an increasing complexities of our technology, management and practices. This paper will contend that perceived improvements in risk control is an illusion of activity, and that the likelihood of mining catastrophes may be exponentially increasing. Although the paper focuses on the mining sector many aspects may be applicable across a range of industries. This paper will further contend that we are applying the right solutions to the wrong problems. Our focus is technological and procedural, while our problem is one of production cultures ripe for error and failure
