With the advent of biotechnology and the ever increasing rate of new biotechnological products into the market, biosensors have seemed to occupy a special place. Be it medical sector or immunological therapies, the application of biosensors is wide spread. A Biosensor can be defined as a device that employs the use of biological components, for instance enzymes, in order to indicate the amount of a biomaterial in a particular environment or body. In Biotechnological terms, a biosensor is an integrated device that has the ability of providing full or semi-quantitative analytical information using a biological recognition element or component that is self-contained and which is in direct contact with a transduction element which then analyzes the results to give an output.

Professor Leland C. Clark Jr. is the man who is considered as the father of biosensors. His main contributions to science were Clark electrode used to measure oxygen in blood, water and other liquids, a Glucose sensor that is used daily by millions of diabetics is based on his research & Oxyxyte which is a third-generation perfluorocarbon (PFC) therapeutic oxygen carrier designed to stimulate the delivery of oxygen to damaged tissues present in the body.

A Biosensor has various components that include an analyte that is generally a molecule like Protein, toxin, peptide, vitamin, sugar, metal ion etc., Sample handling that concerns (Micro) fluidics - Concentration increase/decrease) and Filtration/selection, Detection or recognition and signal. Detection is how you specifically recognize a particle and signal is how you detect if an event of recognition or detection has occurred.

An example of an old time biosensor is a canary. Coal miners used to put a canary in cage to inform them of gas leakage. Various types of biosensors are available in market. Few among them are used very widely, the first one being the pregnancy test. The pregnancy test is used to detect the presence of human gonadotropin hormone (hCG) in the trophoblast cells of the fertilised ovum (blastocyst). hCG was discovered in the year of 1930. However it can also provide false negatives if the test is performed at the early stages of pregnancy because though, hCG is a reliable marker of pregnancy, it cannot be detected until after implantation so it might sometime lead to inaccurate results. Another biosensor used for diabetic patients is the Glucose monitoring device that monitors the glucose level in the blood. Infectious disease biosensor developed by Rapid Biosensor Systems is also in the line. A Cambridge-based technology and business development company, Rapid Biosensor Systems employs the use of technology for rapid screening of infectious diseases. Their first product being "Breathalyser" which is a style device for the screening of Tuberculosis (TB) in a short duration. Structure-wise, the TB Breathalyser consists of an integrated system. The basic components include a disposable sample collection tube (10cm L | 3.5cm W) that is for one time use only and a multi-use reader. The patient is asked to spit some cough into the collection tube. The bottom of this tube consists of a glass bio sensor which is coated with a biochemical. This biochemical coating reacts with the TB bacilli, further insertion of the collection tube into the reader given the ouput after switching of the unit. The collection tube, if necessary, is nebulized at times with a 0.9% saline solution.

In various sectors, the biosensors have developed to be of extensive use. For instance, in bio-pharma research, special purpose biosensors have been designed that are by nature optical, electrochemical etc. Protein chip systems, high throughput systems and drug discovery systems have also been designed. In food and beverage sector, rapid tests for food, bacteria and BSE have been designed for the purpose of food safety. In environmental sector, rapid biochemical oxygen demand (BOD) tests , rapid pollution monitoring systems, tests to indicate the presence of harmful factors in water bodies like lakes, rivers etc. and in environment have been developed successfully. In context of bio-defense, rapid BW detectors, remote & standoff BW detectors and lab-chips for military requirements and anti-terrorism purposes have been designed and successfully implemented too.

The biosensors developed by Rapid Biosensors Systems (RBS) have benefited million users worldwide, especially the TB breathalyser that has made it very easy to do an initial screening of tuberculosis for the check of symptoms and the presence of TB bacilli. The glucose monitoring device mentioned before is also helping users to check their glucose level at regular time intervals. Biosensors are decreasing the need to run to a doctor at every slight appearance of a symptom of a particular disease. By the application of biotechnology, such biosensors are now in market with the use of which, initial screening and testing can be done by individuals themselves.

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Researcher ID- J-4200-2012