Classification and Operational Comparison Analysis of Laboratory Centrifuges

　　Laboratory centrifuges are primarily used in laboratories.

　　Depending on the experimental purpose, different types of centrifuges can be selected.

　　Laboratory centrifuges come in desktop, benchtop, and upright models. For laboratory centrifuges, the difference between desktop and upright models is easily discernible at a glance: typically, those with very small volumes that can be placed on a desk are desktop models, while those with larger volumes that must be placed on the floor are upright models. Desktop laboratory centrifuges generally have a maximum capacity of only 600–800 milliliters, rarely exceeding 1,000 milliliters.

　　Another aspect, from the perspective of speed, is high-speed centrifugation. The term "high-speed" refers to the rotational speed of the centrifuge during operation—specifically, the number of revolutions per minute. High-speed centrifuges typically operate at speeds exceeding 10,000 rpm, while low-speed centrifuges generally run at speeds below 10,000 rpm. However, in typical, everyday applications, high-speed centrifuges usually operate around 12,000 rpm, and low-speed centrifuges typically run at speeds between 4,000 and 5,000 rpm.

　　These data variations can accommodate different experiments.

　　After all, centrifuges have wide-ranging applications in fields such as biomedicine, experimental research, petrochemicals, agriculture, and food hygiene.

　　Based on whether they have a refrigeration function, benchtop centrifuges can be classified into two types: ambient-temperature (non-refrigerated) and low-temperature (refrigerated). Benchtop centrifuges are widely used in experiments involving small sample volumes, numerous steps, high centrifugal forces, and relatively low temperature requirements—such as sample separation in laboratories of biochemistry, genetic engineering, agricultural and forestry sciences, microbiology, food hygiene, hospitals, and other research institutions.

　　As an essential instrument in life science research, the ultracentrifuge boasts high utilization rates and efficiency, and is widely employed in fields such as molecular biology, biochemistry, and proteomics. By means of centrifugation, subcellular components, viruses, proteins, and other biomacromolecules can be isolated, providing a solid foundation for subsequent chemical analyses, biological functional assays, and ultrastructural observations in morphology.

　　However, it’s worth noting that regardless of the type of centrifuge, there are many similar operational details. Take, for example, a high-speed refrigerated centrifuge compared to a conventional centrifuge.

　　1. High-speed refrigerated centrifuge

　　(1) Those who have not undergone training and assessment are not permitted to use it.

　　(2) Select the appropriate rotor and rotational speed; never operate at speeds exceeding the specified limits.

　　(3) Select an appropriate temperature—typically 4℃—and, except for organic solvents, do not go below zero to avoid freezing, which could damage the centrifuge tubes and rotor.

　　(4) Before using the rotor, clean the tube holes thoroughly with a hole-cleaning stick and carefully inspect them for cracks or white spots at the bottom of the holes. If any are found, discard the rotor.

　　(5) The volume of solution loaded into the centrifuge tubes should be appropriate. For stainless steel tubes without caps, fill them only to two-thirds of their capacity; for plastic tubes, fill them up to the shoulder. Ensure that the tube caps are tightly sealed to prevent any leakage. Empty tubes may deform when subjected to centrifugation. When using organic solvents with plastic tubes, make sure to comply with the relevant regulations.

　　(6) Centrifuge tubes must be placed in pairs and strictly balanced, with a deviation of less than 0.1 g.

　　(7) Do not allow the rotor to spin idly without a sample. Use the handle to insert or remove the rotor to prevent it from slipping and falling. Place the rotor gently and ensure it is securely seated. When unscrewing the handle, hold the handle with your hand and rotate only the rotor itself. The rotor cover must be tightly sealed; centrifugation is prohibited without a properly closed cover.

　　(8) Do not open the machine cover during centrifugation, and do not lean against or hold onto the centrifuge. If you hear any unusual noises or notice vibrations, immediately stop the machine.

　　(9) After using the rotor, promptly remove it from the rotor chamber, dry it thoroughly, and carefully clean the tube holes with a hole-cleaning rod. If any solution has spilled, clean it up immediately. Wipe away any condensation inside the rotor chamber, open the door to allow the chamber to air-dry.

　　2. Ordinary centrifuge

　　(1) Before centrifugation, carefully check each hole of the rotor for any foreign objects.

　　(2) Carefully balance the centrifuge tubes.

　　(3) If the inside of the machine is not clean, centrifuge tubes must be sealed with plastic film.

　　(4) Start slowly, then accelerate.

　　(5) Do not open the lid during centrifugation.

　　In summary: Don't skip the standard procedures, and safe experimentation is more important than anything else.