This review is based on the Theophilus Redwood Medal and Award lectures, delivered to Royal Society of Chemistry meetings in the UK and Ireland in 2012, and presents a personal overview of the field of biosensors. The biosensors industry is now worth billions of United States dollars, the topic attracts the attention of national initiatives across the world and tens of thousands of papers have been published in the area. This plethora of information is condensed into a concise account of the key achievements to date. The reasons for success are examined, some of the more exciting emerging technologies are highlighted and the author speculates on the importance of biosensors as a ubiquitous technology of the future for health and the maintenance of wellbeing.

An amperometric enzyme electrode tor the analysis of glucose Is described. The electrode uses a substituted ferrlcinlum Ion as a mediator of electron transfer between Immobilized glucose oxidase and a graphite electrode. A linear current response, proportional to the glucose concentration over a range commonly found In diabetic blood samples (1-30 mM), is observed. Data are presented on the Influence of oxygen, pH, and temperature upon the electrode. Results with clinical plasma and whole blood samples show good agreement with a standard method of analysis.

No abstract

Twenty years on from a review in the first

No abstract

Molecularly Imprinted Polymers (MIPs) are generic alternatives to antibodies in sensors, diagnostics and separations. To displace biomolecules without radical changes in infrastructure in device manufacture, MIPs should share their characteristics (solubility, size, specificity and affinity, localized binding domain) whilst maintaining the advantages of MIPs (low-cost, short development time and high stability) hence the interest in MIP nanoparticles. Herein we report a reusable solid-phase template approach (fully compatible with automation) for the synthesis of MIP nanoparticles and their precise manufacture using a prototype automated UV photochemical reactor. Batches of nanoparticles (30-400 nm) with narrow size distributions imprinted with: melamine (d = 60 nm, = 6.3 × 10 m), vancomycin (d = 250 nm, = 3.4 × 10 m), a peptide (d = 350 nm, = 4.8 × 10 m) and proteins have been produced. Our instrument uses a column packed with glass beads, bearing the template. Process parameters are under computer control, requiring minimal manual intervention. For the first time we demonstrate the reliable re-use of molecular templates in the synthesis of MIPs (≥ 30 batches of nanoMIPs without loss of performance). NanoMIPs are produced template-free and the solid-phase acts both as template and affinity separation medium.

Rapid developments in sensor technology have facilitated the production of devices--known as electronic noses--that can detect and discriminate the production profiles of volatile compounds from microbial infections in situ. Such qualitative and semi-quantitative approaches could have a significant role in the early diagnosis and detection of microbial diseases. Using artificial intelligence and web-based knowledge systems, electronic noses might also have a valuable role in monitoring disease epidemiology.

No abstract