The basic bone of the gel imaging system consists of a CCD camera, darkroom and analysis software. However, its function is not limited to imaging agar enamel gels. Today's imagers tend to be multi-functional, and are also suitable for applications such as protein gels, fluorescing gels, blotting membranes and colony plates.
In terms of Western Blot, the high-performance CCD molecular imaging system is comparable to film. The CCD is an abbreviation of the English name of a Charge Coupled Device and is a photoelectric conversion device. It is the core component of the gel image system. Most people have a certain understanding of digital cameras, and many people are experts in this field. Some people look at the pixels of the digital camera very heavy, but after comparison, it is found that some 4 million, 5 million pixel camera shots are not as good as the 300-pixel machine. Why?
In fact, there are many factors affecting gel imaging. The indicators for measuring CCD quality are resolution, CCD size, dynamic range, sensitivity, quantum efficiency, signal-to-noise ratio, etc. Among them, the number of pixels and CCD size are important indicators. In fact, it refers to the size of the photosensitive device. Here, the larger the area of ​​the CCD sensor, the larger the CCD area, the more photons are captured, the better the photographic performance, and the lower the signal-to-noise ratio. In order to better understand the size of the CCD, the CCD specifications currently applied on the market are as follows:
1 inch - the target size is 12.7mm wide by 9.6mm high and 16mm diagonal.
2/3 inch - the target size is 8.8mm wide by 6.6mm high and 11mm diagonal.
1/2 inch - the target size is 6.4mm wide by 4.8mm high and 8mm diagonal.
1/3 inch - the target size is 4.8mm wide by 3.6mm high and 6mm diagonal.
1/4 inch - the target size is 3.2mm wide by 2.4mm high and 4mm diagonal.
The resolution of CCD is from low to high: from about 450,000, about 1 million, about 1.4 million, about 2 million, about 3 million, about 4 million, about 5 million, and even higher, according to the temperature of CCD Can be divided into normal temperature CCD camera and refrigeration CCD camera, refrigeration CCD: in the same full well electronic CCD, reduce CCD noise, can improve the CCD monitoring ability, hot or dark current is CCD for noise, noise in the Cool CCD basic Can be eliminated by the deep-cooled Peltier. After exposure for more than 5-10 seconds, the CCD chip will heat up. Without the chip of the cooling device, the "hot" or white pixels will cover the image, and the image will be visible everywhere. CCD structure design, digital methods, etc. will affect the noise. Of course, by improving the structure and optimization of the gel imaging system, noise generation can also be reduced.
Fluorescence and chemiluminescence are inherently weak, so the CCD noise reduction is very high. A high-resolution digitally cooled CCD camera combined with a high-pass lens head system should be used to capture the extremely weak fluorescent and chemiluminescent sample images. It also minimizes noise, reduces background and provides excellent image clarity. An optional excitation source and multiple filter wheels expand the range of applications for fluorescence/chemiluminescence imaging. Therefore, it is generally necessary to select a cooling CCD during fluorescence and chemiluminescence observation. Therefore, the refrigeration CCD camera is definitely the future development trend and must be required for the high-end molecular imaging imaging analysis system.
Wood Display Storage Stand,Jewelry Holder Stand,Earring Display Stand,Wooden Jewelry Stand
CSL WOOD ART FACTORY , https://www.cslwoodart.com