Journal articles

This paper will commence with a general introduction to the concepts and technology of biosensors including some discussion of the need for sensors, the range of analytes that can be measured, the areas of application, the construction of sensors with a biological recognition/response system and the range of transducer technologies that are potentially amenable to sensor use. Examples of sensor technologies for the monitoring of substrates, proteins and immunoanalytes will be given. For example.

A glucose sensor comprising a reflection hologram incorporated into a thin, acrylamide hydrogel film bearing the cis-diol binding ligand, 3-acrylamidophenylboronic acid (3-APB), is described. The diffraction wavelength (color) of the hologram changes as the polymer swells upon binding cis-diols. The effect of various concentrations of glucose, a variety of mono- and disaccharides, and the α-hydroxy acid, lactate, on the holographic response was investigated.

Holographic sensors for monitoring ionic strength have been fabricated from charged sulphonate and quaternary ammonium monomers, incorporated into thin, polymeric hydrogel films which were transformed into volume holograms. The diffraction wavelength or reflected colour of the holograms was used to characterise their swelling or de-swelling behaviour as a function of ionic strength in various media. The effects of co-monomer structure, buffer composition, ion composition, pH and temperature were evaluated, whilst the reversibility and reproducibility of the sensor was also assessed.

This work focuses on the GHz frequency limit of the Magnetic Acoustic Resonator Sensor, and how the instrumentation can be modified to support a unique function: the acoustic spectroscopy of interfacial biological films. The optimization route we chose, involved careful characterization of the spiral coil in terms of its S22 reflectivity, and electrical characterisation of the transmission line linking it to our MARS detector.

One of the problems associated with the acoustic biosensor format, is the isolation of the electrical connections, from the liquid test sample. In this paper, we describe our search for an electromagnetic coupling solution, how we modified it for acoustic biosensors, and some of the physical characteristics that we did not anticipate: We began by reviewing the formal descriptions of electromagnetically induced acoustic produced by solid-state physicists of the 1960s, to help understand electronic properties.

Glucose-selective holographic sensors were fabricated from unique tetrahedral 2-acrylamidophenylboronic acid (2-APB) incorporated with co-monomers poly(ethylene glycol) acrylate (PEG), (3-acrylamidopropyl)trimethylammonium chloride (ATMA) and [2-(acryloyloxy)ethyl]-trimethylammonium chloride (AETA) into thin hydrogel films which were transformed into volume holograms using a diffusion method coupled with holographic recording using a frequency-doubled Nd:YAG laser (532 nm).