Precautions for using gel imaging analysis system

With the gradual popularization of molecular biology research, the demand for gel imaging system in China is growing. Regardless of the purpose, the components of gel imaging system are similar, consisting of a shooting system, a dark box with a special light source, and software for acquiring and analyzing gel images.

1. What is a gel imaging analysis system?

Gel imaging is the non-chemiluminescent imaging detection and analysis of different staining of gel electrophoresis such as DNA/RNA/protein (such as EB, Coomassie Brilliant Blue, Silver Staining, SYBR Green) and microplates, flat dishes, etc. Gel imaging system can be used for routine bioengineering research such as molecular weight calculation, density scanning, density quantification, PCR quantification, etc.

2. Classification of gel imaging analysis system
General gel imaging analysis system
Can collect images of protein electrophoresis gel and DNA gel samples and perform qualitative and quantitative analysis. Samples include: nucleic acid monitoring stained with EB, SYBRGreen, SYBRGold, TexasRed, GelStar, Fluoroscecin, RadiantRed, etc.; and protein gels stained with CoomassieBlue, SYPROOrange, various stains, such as Cow dye, etc. (or UV, EB and colored and visible sample imaging).

Chemiluminescence imaging analysis system
The gel imaging system covers UV, EB, chemiluminescence, ultraviolet-fluorescence, colored and visible sample imaging.

Multicolor fluorescence imaging analysis system
The imaging range covers UV, EB, chemiluminescence, multicolor fluorescence, colored and visible sample imaging.

Multifunctional in vivo imaging system UV, EB, chemiluminescence, multicolor fluorescence, colored and visible sample imaging and in vitro tissues and small animals, and large animals.

3. Principle of gel imaging analysis system
The migration rate of samples on electrophoresis gel or other carriers is different. Comparing with standard or other alternative standard products can make a qualitative analysis of unknown samples. This is the basis of qualitative analysis of image analysis system. According to the position of unknown samples in the spectrum, qualitative analysis can be made on them to determine their composition and properties.

The sample partially absorbs the projected or reflected light, so the optical density of the sample band on the image obtained by photography will be different. The optical density is linearly related to the concentration or mass of the sample. According to the optical density of the unknown sample, the concentration or mass of the unknown sample can be obtained by comparing it with the optical density index of the sample band of known concentration. This is the basis of quantitative analysis of image analysis system. The latest ultraviolet transmission light source and white light transmission light source make the light distribution more uniform, and minimize the influence of uneven optical density on the results.

4. Application scope of gel imaging system
In general, gel imaging can be applied to: Gel imaging system can be used for qualitative analysis of separation and purification results of proteins, nucleic acids, peptides, amino acids, polyamino acids and other biological molecules.
Molecular weight quantification
For commonly used DNA films, the molecular weight quantification function is used to automatically generate a fitting curve by annotating the known molecular weight of the DNA Marker band on the gel, and use it to measure the molecular weight of the unknown band. The results obtained by this method are much more accurate than the naked eye observation.

Density quantification
The commonly used method for determining the concentration of DNA (deoxyribonucleic acid) and RNA (ribonucleic acid) is the ultraviolet absorption method, but it can only determine the total nucleotide concentration in the sample, but cannot distinguish the concentration of each length fragment. Using the gel imaging system and software, after calibrating the density of a standard band with a known DNA content on the DNA film, you can easily click on other unknown bands and compare them with the density of the known bands to obtain the unknown DNA content. This method is also suitable for the concentration determination of PAGE protein gel bands.

Density scanning
In molecular biology and bioengineering research, the most commonly used method is to calculate the percentage of protein expression products in the entire bacterial protein. The traditional method is to use dedicated density scanning, but this work can be completed by using biological analysis software combined with a scanner routinely equipped in the laboratory or directly using white light to irradiate the gel imaging.

PCR quantification
PCR quantification mainly means that if the band amplified by the PCR experiment is not one, then the software can be used to calculate the relative percentage of each band in the total band. In terms of this function, it is similar to density scanning, but the actual principle is different. PCR quantification is to perform relative density quantification on the selected bands and calculate their percentage of the total. During density scanning, a longitudinal scanning curve graph is generated for the selected area and integrated.

5. Maintenance of gel imaging system
The maintenance cycle of the gel imager is generally about two weeks. The instrument needs to be kept clean, and the surface periphery is clean; turn on the instrument and software, observe whether the software data cable is in normal contact, and the software operation function is intact.

The instrument computer album should be dedicated to avoid computer virus infection, which will cause it to be unusable. At the same time, it is forbidden to reinstall the system, because the instrument software needs to be reactivated after reinstallation before it can be used.

The correct closing method should be used for the closing operation of the dark box. The specific process is to cover the dark box door to a position of about 60 degrees, let go, and rely on gravity to close the door by itself. It should be noted that it is forbidden to push the dark box door hard to close.

During the normal use and maintenance process, pay attention to keep the UV light box and the projection white light board clean to avoid affecting the gel imaging effect of the gel imager.

In the process of operating the gel imager, in addition to using the instrument correctly, it is also necessary to strictly abide by the laboratory regulations. The gel imaging system can make qualitative analysis for the separation and purification results of other biological molecules such as proteins, nucleic acids, peptides, amino acids, and polyamino acids.

6. Precautions for using the gel imaging system
First turn on the gel imaging system, then turn on the computer and enter the software.
When taking ultraviolet gel photos, prevent EB from contaminating the instrument, and do not touch the door of the gel imaging system with contaminated gloves.
During the process of taking photos with ultraviolet light sources, the front panel of the gel imaging system cannot be opened.
After taking photos, remove the waste glue and wipe it clean with softer paper.
Be gentle when focusing and do not move violently.
Please use a stabilized power supply.
Keep the indoor environment dry and wipe off the water or other liquids left on the observation board in time.
When using the instrument, close the door and observation platform tightly, otherwise the ultraviolet lamp will not be able to be used normally.
Try not to connect the computer to the Internet or LAN, and install antivirus software on the computer to ensure that the computer is dedicated to the specific use.
When the instrument is not used for a long time, please cover the instrument with a dust cover.
To extend the service life of the lamp, please turn off the light source in time after observing the gel.

The gel imaging analysis system is an indispensable tool in molecular biology research and clinical diagnosis. It provides scientists and doctors with powerful diagnostic and research tools through high-precision imaging and advanced software analysis, which helps to understand and treat various diseases. With the continuous development of technology, the performance and application range of the gel imaging analysis system will continue to expand, making greater contributions to the development of life sciences.