Over-the-Counter Biosensors: Past, Present, and Future

Abstract

The demand for specific, low cost, rapid, sensitive and easy detection of biomolecules is huge. A well-known example is the glucose meters used by diabetics to monitor their blood glucose levels. Nowadays, a vast majority of the glucose meters are based on electrochemical biosensor technology. The inherent small size and simple construction of the electrochemical transducer and instrument are ideally suited for point-of-care biosensing. Besides glucose, a wide variety of electrochemical biosensors have been developed for the measurements of some other key metabolites, proteins, and nucleic acids. Nevertheless, unlike the glucose meters, limited success has been achieved for the commercialization of the protein and nucleic acid biosensors. In this review article, key technologies on the electrochemical detection of key metabolites, proteins, and DNAs are discussed in detail, with particular emphasis on those that are compatible to home-use setting. Moreover, emerging technologies of lab-on-a-chip microdevices and nanosensors (i.e., silicon and carbon nanotube field-effect sensors) offer opportunities for the construction of new generation biosensors with much better performances. Together with the continuous innovations in the basic components of biosensors (i.e., transducers, biorecognition molecules, immobilization and signal transduction schemes), consumers could soon buy different kinds of biosensing devices in the pharmacy stores.

Electrochemical techniques and sensors for ocean research

“…Despite its complexity -the device involves biochemical, chemical and electrochemical reactions all coupled to form a highly specific transducer -it is mass produced (several millions of strips per month) and used by millions of diabetic patients worldwide. Similar approaches are being investigated for other metabolites (Lee, 2008). An increasing range of biological entities are being probed electrochemically, e.g.…”

“…The measurement of charge, known as coulometry, is the basis of some sensors, e.g. the personal blood glucose sensors used by diabetics (Lee, 2008). Another very common waveform is the potential ramp, see Table 4.…”

“…but the most common form of modification is obtained by electrodeposition (Situmorang et al, 2001). Probably the most well known and successful bioelectrochemical sensor is the blood glucose sensor which involves a glucose oxidase modified electrode (Bartlett and Toh, 2004;Lee, 2008). Despite its complexity -the device involves biochemical, chemical and electrochemical reactions all coupled to form a highly specific transducer -it is mass produced (several millions of strips per month) and used by millions of diabetic patients worldwide.…”

Electrochemical Glucose Biosensors for Diabetes Care

“…Technological advances have allowed systems to be useful over wide temperature, hematocrit, and blood glucose range, while test time and sample size have decreased dramatically [52, 220,221]. SMBG is part of the necessary toolkit for managing T1 and T2 diabetes.…”

Recent Trends in Field-Effect Transistors-Based Immunosensors

“…For example, the most utilized enzyme immunoassay in clinical analysis and residual analysis in environmental and food samples is the label-based enzyme-linked immunosorbent assay (ELISA) [10]. The ELISA test basically consists of translating the recognition event between a specific enzyme-labeled antibody and an antigen into a colorimetric, chemiluminescent, or electrochemical signal [11,12]. Radioimmunoassay (RIA) is also used in clinical diagnosis and involves the use of radiolabeled antigens or antibodies [13].…”