This article focuses on the application, use and maintenance of centrifuges. It provides a general introduction from the correct operation and use methods, daily maintenance, troubleshooting, and the requirements for safe use, and briefly looks at the speed control and rotor of today’s centrifuges. , Microcomputer applications, security and standardization and other key technologies.
Centrifuge is a kind of high-speed rotating machinery with complex structure. It uses centrifugal force and the difference in precipitation speed of different substances in the centrifugal field to quickly separate the mixed solution. It is a kind of centrifuge tube containing sample solution, The bottle or bag rhyme rotor is placed on the centrifugal shaft, and the powerful centrifugal force generated by the high-speed rotation of the rotor around the shaft is a special device that separates particles of different properties in the sample. , Can realize the analysis and separation of samples.
Since its inception, centrifuges have undergone low-speed, adjusted, and over-speed changes, and their progress is mainly reflected in the design of the centrifuge and the technology of centrifugation, which complement each other. Due to the simple structure, low cost and small size of the benchtop centrifuge, it soon became a routine instrument in the laboratory. Almost all well-known centrifuge manufacturers at home and abroad produce benchtop centrifuges, such as the German Hheraeus, eppendof, and Sigma which have been active in my country in recent years. , Hettich, Hermle, Jouran in France, Beckman, Sorvall, IEC in the United States, Hitachi, Kukna, Sanyo/Mse in Japan, etc., domestic Beijing Medical Centrifuge Factory, Hunan Kaida Scientific Instrument Co., Ltd., Shanghai Anting Scientific Instrument Factory Wait. From the perspective of rotation speed, the desktop centrifuge basically belongs to the category of low-speed and high-speed centrifuges, so it has the characteristics of low-speed and high-speed centrifuges. Compared with floor-standing centrifuges, it is only smaller in size and capacity.
There are many styles and models of centrifuges, including domestic and imported ones. According to their use, they can be divided into analytical centrifuges and preparative centrifuges; according to the speed, they can be divided into:
Ordinary centrifuge (low speed) <8000r/min;
High-speed centrifuge 8000～30000r/rain;
Ultra-speed centrifuge 30000～80000r/min;
Ultra-high speed centrifuge>80000r/min;
Choose centrifuges according to biological high molecular weight:
Molecular weight>10. , Using ordinary centrifuges and high-speed centrifuges;
The molecular weight is 10-10. , Using an ultracentrifuge;
If the molecular weight is less than 10, the effect of centrifugation and ultracentrifugation is not good, and another separation method must be used.
The centrifuges with different capacities, different speeds, and different temperature controls can be selected according to the purpose and needs of the experiment. For example, when you need to centrifuge at room temperature, small amount, and fast, you can use a palm centrifuge (LX-100 type, produced by Jiangsu Haimen Kylin Medical Instrument Factory) and a micro centrifuge (DW-41 type, South Korea KOREA); if the required speed is not Above 16000rpm, you can use a benchtop centrifuge (Hettich, Germany, MIKRO12-24 type; for small amount of plasmid DNA extraction, cDNA extraction experiments, protein extraction, and RNA extraction from plants, the speed needs to be 12000-140000rpm, often using high-speed refrigerated benchtop centrifuge Machine (German Hettich, 16R and 32R), desktop high-speed centrifuge (German HettichMIKRO12-24) and high-speed refrigerated centrifuge (French JOURNBR4i); when preparing competent cells and extracting large amounts of plasmid DNA, automatic High-speed refrigerated centrifuge (Japan HITACHI, Hitachi Koki Co., Ltd., 20PR-52D) and ultra-high-speed refrigerated centrifuge (Beckman Avant U-301, USA) type; if a large amount of centrifugation is required, for example, 50mL, 100mL or more than 100mL, and the speed needs to be 20000 ~70000rpm, you can use an automatic ultra-speed freezing centrifuge (Japan HITACHI, Hitachi Koki Co., Ltd., 70P-72 type).
Among the above-mentioned centrifuges, the more advanced is the American BeckmanAvantiJ-301 ultra-high-speed refrigerated centrifuge. Its performance is superior. It integrates vacuum, high-speed and cooling. It can be used for a large number of cells, sub-cells, bacteria, and bacteria. Separation is a common laboratory equipment. Centrifuges with a speed in the range of 5000～30000RPM (revolutions per minute) are usually called high-speed centrifuges. The z* high speed of the BeckmanAvantiJ-301 centrifuge is 30000RPM, so it belongs to high-speed centrifugation. Range of the machine.