Centrifuge is the use of the centrifugal force of the mixture (with solids) and precipitation for the separation of a special apparatus. Laboratory used a low-speed electric centrifuges, the high-speed centrifuges and low-speed, high-speed refrigerated centrifuge, as well as speeding analysis, prepared frozen centrifuges and other dual-use model. Among them, low-speed (including high-capacity) high-speed centrifuges and centrifuge frozen most widely used, biological and chemical laboratory was used to the separation of biological macromolecules essential for the preparation of an important tool. In the experiment, with the precipitation to save mother liquor separate from the regular use of centrifugal filter and the two methods. But in the following cases, the use of centrifugal method better. 

    ① precipitation there is viscous or thick mother liquor. 

    ② small particle precipitate easily through the filter paper. 

    ③ excessive sedimentation and osteoporosis. 

    ④ small amount of precipitation, the need for quantitative analysis. Mother liquor, or very little volume, should be separated to reduce the losses. 

    ⑤ precipitation and the mother liquor must be separated. 

    ⑥ general colloidal solution. 

    ① ordinary (non-refrigerated) centrifuge 

    Such centrifuge relatively simple structure can be divided into small desktop and floor-categories, with motor-driven, the governor, timer devices and so on, easy to use. Its low-speed centrifuge speed less than 4000rpm, high-speed desktop centrifuge maximum speed of up to 18000rpm. 

    ② low-speed refrigerated centrifuge 

    Speed less than 4000rpm, the largest with a capacity of 2-4L, is the most commonly used laboratory isolated a large number of primary extraction of biological macromolecules, such as sediment. Turn their back on their use of aluminum-casting system and two-angle, centrifugal possession of hard glass, polyethylene plastic and stainless steel hardware variety of models. There are motor-driven centrifuge assembly, timer, the regulator (the speed of instruction) and refrigeration systems (adjustable temperature range of -20 - +40 ℃), under the centrifugal material needs to switch to a different capacity and speed of different models of the other way round . 

    ③ high-speed refrigerated centrifuge 

    20000rpm more than up to speed, with the exception of low-speed refrigerated centrifuge with the performance and structure, high-speed centrifuges used-angle turn are made of aluminum and titanium alloys used. centrifuge tube covered with polyethylene for hard plastic products. Such centrifuges are used to collect micro-organisms, cell debris, cells, the cells, immune, as well as sulfuric acid sediment sediment, and so on. 

    ④ speed centrifuges 

    50000rpm more than up to speed to make this sub-cellular-grade separation, and for proteins, nucleic acids, such as molecular weight determination. To turn their back on their high-intensity made of titanium alloy, according to the need to switch to a different capacity and speed of different types of turn. Speeding motor-driven centrifuges there are two types of frequency modulation for direct electric-speed, and the other to speed up the adoption of Biansuchilun me. In order to prevent the motor-driven high-speed operation in the heat of the middle class, equipped with a motor-driven cooling system (air, water), speed limiter, when the mind, speed recorder, and so on. In addition, the speed centrifuge assembly also have a vacuum system. 

    (1) centrifuge usually have registration forms, please use the pre-registered users to do, turn Tuo, speed and time. 

    (2) must be tube balance, centrifugal Add Tuo must also pay attention to a balanced position. Never more than centrifuges or centrifuge Tuo maximum speed limit. 

    (3) must meet the pre-set speed before leaving the centrifuge; Yizhuang if any, should be immediately shutdown. 

    (4) usually listen to the voice of centrifuge that is the normal situation, but also pay attention to the centrifuges where vibration. 

    (5) such as the use of ammonium sulfate salt solution samples, must be cleaned centrifugal Tuo, but also to clean centrifuge module. 

    (6) high-speed centrifuges due to high speed, but also more complex and require additional specialized training before they can use. 

    (1) over high-speed centrifuge why frozen or vacuum? 

    (2) you have to be very careful to balance the two sample centrifuge tubes, but running centrifuges, or the imbalance occurred, stands out again after a scale and found two pipe or centrifugal balance, may I ask why do not occur Balance? 

    (3) of centrifugal Godot generally divided into the hanging basket swing bucket-angle and angular two major categories, the difference between the use? 

    (4) general paper records of the centrifuge, such as the speed record was 8,000 rpm, centrifugal gravity ? was recorded as 10,000 g, What's the difference between the two? Is more appropriate? 

     

    (1) the use of temperature settings usually 4 ℃, the first centrifugal Tuo into centrifuge cabin, to the attention of centrifugal Tuo axis of good cards; closed the door, centrifugal cabin temperature started to decline, pre-cooling time should be sufficient. 

    (2) the samples into the appropriate centrifuge tubes, with both balance the weight balance, centrifuge tubes covered with lid and tightened up. 

     ◆ attention to the centrifuge tube fitted only 70 per cent full, although there are additional cover, but it may be too strong centrifugal force and leaking. 

     ◆ Most of the centrifuge tubes are attached to the lid, cover the attention of the centrifuge tubes together to balance. 

     ◆ centrifuge tubes usually on the ice, pay attention to balance out, the crushing of the liquid should wipe clean. 

     ◆ single drop of centrifuge tubes to use one of the centrifuge tube equipped with a water balance. 

    (3) the balance of good centrifuge tubes symmetrically into centrifuge Tuo, covered with lid of the centrifugal Tuo, pay attention to whether or not tightened up. 

     ◆ If the lid of the centrifugal Tuo not tightened up, centrifugal will come out, causing great harm! 

    (4) closed the door centrifuges, in the dashboard up to be a good time with the speed of ? such as the 8,000 rpm ? 30min. 

     ◆ attention to the use of speed can not exceed the limit centrifugal Tuo, the maximum speed is usually written on the steep bank above centrifuge, for example, TGL-20M for the maximum speed 20,000 rpm, if the centrifuge is too old to be cut down. 

     ◆ speed and time as far as possible not to set too high, for example, be able to use 7,000 rpm are not to use 8,000 rpm. 

    (5) to identify all the correct steps, according to the Start button start, gradually speed up the centrifuge, at this time should be closely monitored. 

     ◆ some old-time knob, set the following 5min, 10min and then turned back to the first 5min. 

     ◆ press the Start button, hold down the time not too short, sustained by about one second after release. 

     ◆ started to accelerate when the most dangerous, if not sound, or have a big shock, immediately press Stop. 

    (6) to be achieved until the centrifugal speed, can be left to determine everything will be all right. 

    (7) to complete centrifuge, centrifuge to wait for Godot completely static, in order to open the door; centrifuge tube removed as soon as possible, to fully observe the centrifuge tubes, as well as the location of precipitation, the supernatant poured out as soon as possible, be careful not to precipitate Get turbidity. 

     ◆ matter to the supernatant or precipitation, access to clean beaker supernatant collected, in order to avoid mistakes. 

     ◆ supernatant dumping must be very careful so as not to precipitate out back together; if inadvertently mixed, it is necessary to Zhonglaiyici. 

     ◆ If You Lou centrifuge tubes, it is necessary to find out the reasons, and immediately clean up or centrifugal Tuo centrifuge module. 

    (8) in the gap between the two centrifugal, centrifugal Tuo not out, but the cover door, not to let hot air into the centrifuge module. 

    (9) all use after the clean-out Tuo centrifuge can be used to tap water rinse and dry rewind. Centrifuge to open the door, such as the ice melted, and wipe clean up a little longer, if leakage of liquid, use water to wash it. Check back to balance the scale centrifuge tubes, as well as desktop, it is easy to dirty, it is necessary to carefully clean up before leaving.