The sensor contains bioactive materials such as antibodies, antigens, proteins, DNA, or enzymes.

1. Features and applications of biosensors
1.Principle and structure
The sensor contains bioactive materials such as antibodies,
antigens, proteins, DNA, or enzymes. After the test
substance enters the sensor, the molecule recognizes it and
then a biological reaction occurs to generate information.
The information is converted into sound and light by a
chemical or physical transducer. Signal, electricity, etc.,
the instrument will output the signal, we can get the
concentration of the substance to be measured. The main
components of the sensor are the susceptor and the
transducer, and then the signals are processed through
automated instrument technology and microelectronic
technology to form various instruments or systems.

2. 2. Classification and characteristics
According to the type of transducer, it can be divided into
acoustic wave sensors, semiconductor sensors, thermal
sensors, impedance sensors, etc .; according to the type of
molecular recognition elements, it can be divided into
immune sensors, cell sensors, and tissue sensors.
Most of the traditional medical tests are enzyme analysis
methods. This method is complicated and expensive, and the
biosensor method can be used multiple times although the
reagents are expensive; the biosensor has a strong
transferability, which is only for specific The substrate
reacts, regardless of its turbidity and color. Furthermore,

3. the analysis speed is fast, and the result can usually be
obtained in one minute. The error can be controlled within
1%, and the accuracy can be guaranteed. Compared with the
enzyme analysis method, the operation is simpler, Automated
analysis is possible; biosensor inspection is more
efficient. The above are all advantages of biosensors.
3. Application in the medical field
There are many kinds of biosensors, and the analysis of the
application of several kinds of sensors in the medical
field is carried out below.
3.1 Microbiological sensors
The susceptor of a microbial sensor is a membrane
containing microorganisms. The working principle is that
microorganisms consume dissolved oxygen in the solution to
be tested, emit heat or light, and achieve the purpose of
quantitatively detecting the substance to be tested.
Compared with enzyme sensors, microbial sensors are more
stable and cheaper to use, but the scope of use is less
than that of enzyme sensors. Data show that the microbial
sensors can detect about 60 to 70 species. Microbes will be

4. affected by the poison of the test substance. This is the
main factor that affects the accuracy and life of the
sensor. This problem is resolved, and the market for
microbial sensors is just around the corner.
3.2 Enzyme sensor
The sensor's sensitive element is an immobilized enzyme.
Using an enzyme sensor does not require a lot of effort to
extract the enzyme. Enzymatic sensors can be used to
determine biochemical indicators such as urea, glucose,
lactic acid, and asparagine in clinical practice. For
example, the current glucose sensor has developed to the
fourth generation, which has a wide range of applications,
and the technology of lactase sensor has been quite mature
internationally. To test the patient's renal function
clinically, a renal function diagnosis is required, and
then artificial dialysis is performed in a targeted manner.
In this case, a urea sensor is used. Enzyme sensors have a
long research and development time. There are more than 200
types of enzyme sensors on the market.
3.3 Gene Sensor

5. Gene sensor is a kind of sensor that has only appeared in
recent years, but its technology is advanced. There are
also many experts and scholars at home and abroad to study
gene sensors. The basis of a gene sensor is high
specificity for hybridization. Generally, there are about
30 single-stranded nucleotide nucleic acid molecules on a
gene sensor. The target nucleic acid molecule is determined
by hybridizing with a target sequence. At present, more
genetic sensors are researched and used as DNA sensors,
which are mainly used for the detection of tuberculosis,
HIV and hepatitis B virus, so as to achieve the purpose of
diagnosing diseases.