I. Biosensors
Biosensors can be classified in many ways: Based on the living material used in their sensors, they can be divided into: microbial sensors, immune sensors, tissue sensors, cell sensors, enzyme sensors, DNA sensors, etc. Based on the detection principle of the sensor device, they can be divided into: thermal biosensors, field-effect transistor biosensors, piezoelectric biosensors, optical biosensors, acoustic wave biosensors, enzyme electrode biosensors, mediator biosensors, etc. Based on the type of interaction between the biosensor and the sensing substance, they can be divided into affinity-based and metabolite-based types.
A biosensor is an instrument that senses biological substances and converts their concentration into an electrical signal for detection. The characteristics of biosensors generally include: using immobilized bioactive substances as catalysts; reusing expensive reagents multiple times, overcoming the drawbacks of high reagent costs and complex chemical analysis in traditional enzymatic methods; high specificity, reacting only with specific substrates and unaffected by color or turbidity; fast analysis speed, with results available in one minute; high accuracy, typically with a relative error of 1%; simple operating system, easily enabling automated analysis; low cost, requiring only a few cents per measurement for continuous use; and some biosensors can reliably indicate the oxygen supply and byproduct production within a microbial culture system. In production control, they can obtain information that would otherwise require the combined action of many complex physicochemical and displacement sensors. Furthermore, they indicate directions for increasing product yield.
Understanding biosensors is very helpful, especially given their current popularity. We must know about biosensors in order to use them effectively.
II. Applications of Biosensors
1. Detecting DNA mutations
The new electrographene biosensor chip may be the first chip used in biomedical implants to read and detect DNA mutations in real time. It represents an inexpensive biosensor technology capable of high-resolution detection of human gene mutations and wirelessly transmitting data to mobile devices.
This technology could lead to a new generation of diagnostic methods and personalized treatments, as the biosensor chip can be used for biopsies and detailed DNA sequencing. Because the chip is connected to graphene transistors, it allows it to operate electronically—making it the first product to combine dynamic DNA nanotechnology with high-resolution electronic sensing.
2. Disease Diagnosis
A new biosensor can detect specific molecules associated with neurodegenerative diseases and several different types of cancer. The device is designed to react upon contact with glutathione S-transferase, an enzyme linked to Parkinson's disease, Alzheimer's disease, breast cancer, and other conditions.
This device is an organic nanoscale transistor on a glass substrate. It uses a nanoscale system to recognize specific molecules and can be used to diagnose complex diseases quickly and safely.
The device's portability and low cost make it suitable for any real-life environment, and it can be adapted and improved to detect other substances or molecules associated with different diseases. The team ultimately plans to create a paper-based biosensor to further improve portability and cost.
3. Virus testing
Biosensing technology can play an important role in virus detection. A new nanobiosensor can detect a variety of different viruses in just 2 to 3 hours.
Traditional testing methods may take one to three days to complete; however, this new biosensor uses frequency-enhanced luminescent resonance energy transfer (LRET) for ultrasensitive virus detection in liquid systems.
The technology is simple to design and operate, requiring no expensive equipment or specialized skills. It is also designed to identify the genetic sequences of virtually any known target virus. Sooner or later, this technology could even be adapted and improved to identify multiple influenza viruses on a single testing platform.
