Centrifuge is a very common laboratory separation instrument, widely used in biomedicine, petrochemical, agriculture, food hygiene and other fields. Since the advent of centrifuge, it has gone through the changes of low speed, adjustment and overspeed, and its progress is mainly reflected in centrifugal equipment and centrifugal technology, which complement each other. From the speed point of view, the desktop centrifuge basically belongs to the category of low speed, high speed centrifuge, the development of the general desktop centrifuge has blurred the line of low speed, high speed, trace and large capacity centrifuge, many turning head for scientific research personnel to provide a wide range of applications, become the preferred model of scientific research laboratory.
Centrifuges seem to be simple to use and have no technical content, but it is necessary to use and maintain correctly. Once a failure occurs, it is not worth the loss to delay the experiment. The following describes the operation procedures of two common types of centrifuges and the matters needing attention when using them:
Low speed centrifuge operation process
1.The centrifuge placed on a flat table or platform, four rubber machine feet should be solid contact with the plane, visual balance, gently shake the centrifuge, check whether the centrifuge is placed smoothly.
2.Open the door cover and put the centrifugal tube into the rotor body. The centrifugal tube must be placed symmetrically in even numbers (the test liquid of the centrifugal tube should be weighed and added).
3.close the door cover, pay attention to make sure that the door cover lock, check whether the door cover is closed by hand.
4.Plug in the power socket and press the power switch.
5.Set the rotor number, speed, temperature and time:
In the stop state, the user can SET the rotor number, speed, temperature, time, press the SET (SET) key, at this time the centrifuge is in the SET state, stop light, running light flashing; In the running state, the user can only SET the speed, temperature and time, press the SET (SET) key, then the centrifuge is in the setting state, the running light is on, the stop light is flashing (press the “SET” key to choose between time, temperature, speed and rotor number in the stop state; Press “SET” to select between time, temperature and speed.
(1) SET the rotor number: press the “SET” key, when the decimal point at the lower right corner of the rotor digital tube is bright, that is, enter the rotor number setting, and then press the “▲” or “▼” key to select the centrifuge this work with the rotor number, a total of six kinds of rotor to choose, note: SET the rotor number to be consistent with the selected rotor, can not be SET wrong.
(2) SET speed: press the “SET” key, when the last speed of the digital tube at the lower right corner of the decimal point is bright, that is, enter the speed setting, and then press the “▲” or “▼” key to determine the speed of the centrifuge this work.
(3) SET the temperature: press the “SET” key, when the temperature of the last digital tube at the lower right corner of the decimal point is bright, that is, enter the temperature setting, and then press “▲” or “▼” to determine the centrifuge working temperature.
(4) SET the time: press the “SET” key, when the last digital tube at the lower right corner of the decimal point light, that is, enter the time setting, and then press the “▲” or “▼” key to determine the centrifuge this work time (the maximum time is 99 minutes), the time is countdown.
(5) After the above four steps are completed, press “ENTER” again to confirm the rotor, speed, temperature and time set above, and then press “START” to START the centrifuge.
(6) in the operation, if you want to see the centrifugal force, press the “RCF” key (RCF light on), it will display the centrifugal force under the speed at that time, 3 seconds after the automatic return to the operation state; The centrifuge enters the setting state when it is running. If you want to cancel the setting, press the “RCF” key to return to the running state.
6.centrifuge time countdown to “0”, the motor power, 5 seconds after the brake, centrifuge will automatically stop, when the speed is equal to 0 r/min, the buzzer beep 15, press the “RCF” key can cancel the beep; Press “STOP” during operation, the centrifuge stops running and the buzzer does not sound.
7.When the rotor stops, open the door cover and take out the centrifugal tube.
8.Turn off the power switch and power off the centrifuge.
Operation flow of high speed refrigerated centrifuge
1.Set the service temperature (usually 4℃, first put the rotor into the centrifugal chamber, pay attention to the rotor to clamp the shaft; Close the door, the temperature of the centrifugal chamber begins to drop, and the pre-cooling time should be sufficient.
2.Load the sample into the appropriate centrifuge tube, balance the weight with a balance, close the centrifuge tube lid and screw it tight.
◆ Note that the centrifugal tube is only 70% full, although there is a lid, it may leak due to the strong centrifugal force.
◆ Most centrifugal tubes are attached with a cover, pay attention to the cover of the centrifugal tube should be balanced together.
◆ Centrifugal tube is usually placed on broken ice, pay attention to remove the balance, to wipe the liquid of broken ice clean.
◆ The single centrifugal tube should be balanced by another centrifugal tube with clean water.
3.Place the balanced centrifugal tube symmetrically into the rotor, and cover the rotor with the cover, paying attention to tightening.
◆ If the cover of the rotor is not tightened, it will fall out when centrifugation, causing great damage!
4.Close the centrifuge door and adjust the desired speed and time on the instrument panel, for example, 8000rpm,30min
◆ Note that the speed must not exceed the limit of the rotor, the maximum speed is usually written on the rotor, for example, the maximum speed of TGL-20m is 20000 RPM, but if the centrifuge is too old, must be lowered.
◆ Speed and time setting should not be too high.
5.Confirm all steps are correct, press the start button to start, centrifuge gradually accelerate, at this time to closely monitor.
◆ Some old time knob, set below 5min, to turn 10min and then back to 5min.
◆ Press the start button, hold down the time can not be too short, please continue to press for about one second before releasing.
◆ The start of acceleration is the most dangerous, if the sound is not correct, or there is a big vibration, please immediately press Stop.
6.Wait until centrifugation reaches the desired speed, make sure everything is normal before leaving.
7.When centrifugation is completed, the door can only be opened after the rotor is completely stationary; Please take out the centrifuge tube as soon as possible. First observe whether the centrifuge tube is complete and the position of precipitation. Pour out the supernatant as soon as possible, and be careful not to make the precipitation cloudy.
◆ No matter what supernatant or precipitate is needed, please collect supernatant in a clean beaker to avoid mistakes.
◆ Dumping on the clear to be very careful, so as not to pour out the precipitation together; If it gets mixed up, start again.
◆ If the centrifugal pipe leaks, find out the reason, and immediately clean the rotor or centrifugal chamber.
8.In the gap between the two centrifuges, it is not necessary to take out the rotor, but cover the cabin door to prevent hot air from flowing into the centrifugal chamber.
9.After all use, remove the rotor clean, can be washed with running water, and put upside down to dry. The centrifugal door should be opened, and then slightly wiped and cleaned after it freezes and melts. If any liquid leaks out, it should be washed with clean water. Also check the balance of the centrifugal tube and the table top, it is easy to get dirty, carefully clean before leaving.
Precautions for use of centrifuge
- Centrifuge in the pre-cooling state, the centrifuge cover must be closed, centrifuge after the end of the head to be inverted on the experimental table, dry the remaining water in the chamber, centrifuge cover in open state.
- The turnhead cover can be placed on the platform of the centrifuge or on the experimental table during pre-cooling. Do not float on the turnhead without tightening it, because once it is wrongly started, the turnhead cover will fly out, causing an accident!
- After tightening the rotating cover, be sure to touch with your fingers whether there is any gap between the rotating head and the rotating cover. If there is any gap, unscrew it and tighten it again until it is confirmed that there is no gap before starting the centrifuge.
- In the centrifuge process, the operator shall not leave the centrifuge room. In case of abnormal situation, the operator shall not turn off the POWER (POWER), but press STOP. Fill in centrifuge usage record before pre-cooling.
- Fake and inferior centrifugal tubes and aging, deformation and cracked centrifugal tubes shall not be used.
- The bottom of centrifuge casing should be padded with cotton or tube pad.
- If there is noise or fuselage vibration of the electric centrifuge, the power supply should be cut off immediately and the fault should be eliminated immediately.
- The centrifugal tube must be placed symmetrically in the casing to prevent the fuselage from vibration. If there is only one sample tube, the other one should be replaced with equal quality water.
- When starting the centrifuge, cover the top of the centrifuge before slowly starting it.
- After the separation, close the centrifuge first. After the centrifuge stops rotating, open the centrifuge cover and take out the sample.
- The centrifugal tube must be well balanced, and the position of the rotor must be balanced. Never exceed the maximum speed of the centrifuge or rotor.
- Be sure to leave the centrifuge after reaching the preset speed; If anything goes wrong, shut it down immediately.
- Usually, you can know whether the centrifugal condition is normal by listening to the sound, and you can also pay attention to the vibration of the centrifuge.
- After using high-salt solution samples such as ammonium sulfate, be sure to wash the rotor and clean the centrifugal chamber.
- Ultra-high-speed centrifuges are more complex because of their high speeds and require additional specialized training.
