ELIASA, also known as enzyme-linked immunoassay, is an instrument widely used in biological experiments, medical tests and chemical analysis. It uses enzyme-linked immunotechnology to detect specific reactions of antigens and antibodies to achieve quantitative or qualitative analysis of biological samples. This paper will introduce in detail the working principle, application field, classification, use precautions and so on.
First, the working principle of the enzyme label instrument
The core technology of ELISA is enzyme-linked immunotechnology, which is a technique that combines enzyme and immunological methods. In enzyme-labeled assay, an antigen or antibody is fixed to a specific support and then reacts with the corresponding antibody or antigen. During the reaction, the enzyme-labeled antibody or antigen will bind to the antigen or antibody on the support to form a complex. By adding the substrate, the enzyme catalyzes the hydrolysis of the substrate into a colored product, and the amount of the product is positively correlated with the concentration of the substance to be measured. Finally, the absorbance of colored products was detected by enzyme-labeled instrument, and the concentration of the substance to be measured was calculated.
Second, the application field of enzyme labeling instrument
The application field of enzyme labeling instrument is very wide, mainly involving biological experiment, medical examination and chemical analysis. In the field of biological experiments, enzyme labels are used to detect biological molecules such as proteins, enzymes, hormones, antigens and antibodies. In the field of medical examination, the enzyme marker is used to diagnose infectious diseases, autoimmune diseases, tumors and other diseases. In the field of chemical analysis, enzyme-labeled instruments are used to detect harmful substances such as pollutants and drug residues in the environment.
Iii. Classification of enzyme label instrument
According to the different detection principles and application scenarios, the enzyme marker can be divided into many types. Here are some common categories:
According to the different detection wavelength, the enzyme marker can be divided into visible light enzyme marker and ultraviolet visible spectrophotometer. Visible light enzyme marker is suitable for the detection of visible light, mainly used for the detection of proteins, enzymes and other substances; Ultraviolet-visible spectrophotometer is suitable for the detection of ultraviolet and visible light, mainly for the detection of organic matter.
According to the different sample size, the enzyme labeling instrument can be divided into single channel enzyme labeling instrument and multi-channel enzyme labeling instrument. The single-channel marker can only detect one sample at a time, while the multi-channel marker can detect multiple samples at the same time, which improves the detection efficiency.
According to the different degree of automation, the enzyme labeling instrument can be divided into automatic enzyme labeling instrument and semi-automatic enzyme labeling instrument. Fully automatic enzyme marker can realize fully automated operation, including sample addition, washing, testing and other steps; The semi-automatic enzyme marker needs to complete part of the operation manually.
According to the different application scenarios, the enzyme labeling instrument can be divided into multi-function enzyme labeling instrument and special enzyme labeling instrument. Multifunctional enzyme marker is suitable for a variety of detection needs, including protein, enzyme, hormone and other substances detection; Special enzyme marker is designed for specific detection needs, such as chemical analysis enzyme marker, environmental monitoring enzyme marker and so on.
Iv. Precautions for the use of enzyme marker
When using the enzyme marker for detection, the following points need to be noted:
Ensure that the reagents and samples used comply with the requirements of the enzyme marker and avoid the use of expired or unqualified reagents.
Before use, it is necessary to calibrate the enzyme marker to ensure that the instrument is in normal working condition. Calibration can be carried out by standard to ensure instrument accuracy.
In the process of detection, attention should be paid to the control of temperature and humidity to ensure the consistency of experimental conditions.
When reading the data, it is necessary to select the appropriate wavelength and time point. When selecting the appropriate wavelength, it is necessary to pay attention to the difference in the maximum absorption wavelength of different substances, and the appropriate wavelength should be selected according to the nature of the object to be measured. At the same time, it is necessary to pay attention to the influence of background interference, and selecting the appropriate wavelength can reduce the influence of interference on the result. In addition, it should be noted that different wavelengths correspond to different substance detection ranges and sensitivities, so in practical applications, the appropriate wavelength needs to be selected according to the specific situation.
When selecting the time point, it is necessary to pay attention to the reaction time of the substance to be measured and the color time of the substrate. Too short reaction time may lead to incomplete reaction and affect the accuracy of results. Long reaction time may increase the influence of non-specific binding and background interference. Therefore, it is necessary to choose the appropriate time point according to the specific situation of the experiment. At the same time, it should be noted that overexposure or underexposure of the substrate should be avoided when reading the data.
During use, it is necessary to pay attention to instrument maintenance and maintenance. Regular cleaning of instrument surfaces and internal components avoids cross-contamination and extends instrument life. At the same time, it is necessary to pay attention to whether the working environment and power supply conditions of the instrument meet the requirements.
In terms of data processing, it is necessary to pay attention to the accuracy and reliability of data. Outliers or outliers need to be properly handled and analyzed. At the same time, attention should be paid to the comparability and repeatability of data to ensure the reliability and repeatability of experimental results