Laboratory centrifuge bottle is a container used for holding samples to be centrifuged in laboratory centrifugation operations.

1. Structural Features

• Material:
  Centrifuge bottles are usually made of high-strength plastics (such as polycarbonate, polypropylene, etc.) or glass. Plastic centrifuge bottles have good chemical resistance and can withstand a variety of chemical reagents. They are also lightweight and less likely to break, making them relatively safe to use. For example, when dealing with samples containing organic solvents, polycarbonate centrifuge bottles can effectively resist the erosion of solvents. Glass centrifuge bottles, on the other hand, have better transparency, which is convenient for observing the state of samples before and after centrifugation. Moreover, they are more favored in some experiments with extremely high purity requirements (such as the separation of biological products), because glass materials are relatively pure and are less likely to release impurities that could affect the samples.
• Shape and Capacity:
  The shape of centrifuge bottles is generally cylindrical, with the bottom being conical or round. This shape helps with the precipitation and layering of samples during the centrifugation process. Centrifuge bottles come in a variety of capacity specifications, ranging from dozens of milliliters to several liters. Common ones include 50 ml, 100 ml, 250 ml, 500 ml, etc., to meet the centrifugation needs of samples with different volumes. For example, in small-scale cell centrifugation experiments, 50 ml or 100 ml centrifuge bottles can be used; while in large-scale protein extraction and other experiments, 500 ml or even larger capacity centrifuge bottles may be required.
• Sealing Design:
  Centrifuge bottles are equipped with sealing caps to prevent sample leakage during high-speed centrifugation. There are various designs for the sealing caps. Some are screw caps, which can achieve a good sealing effect by being screwed tightly; others come with rubber gaskets or sealing rings to enhance the sealing performance. For example, when centrifuging samples containing volatile reagents at high speed, well-sealed centrifuge bottles can avoid reagent volatilization and leakage, ensuring the safety of laboratory personnel and the accuracy of the experiment.

2. Uses

• Biological Sample Processing:
  In cell biology experiments, centrifuge bottles are used for collecting and washing cells. For example, after cell culture, cells are separated from the culture medium in centrifuge bottles. The supernatant (culture medium) is removed, and then new washing solution is added for washing. After repeating the centrifugation process, pure cell pellets can be obtained for subsequent experiments, such as cell lysis and nucleic acid extraction. In the processing of blood samples, centrifuge bottles can be used to separate plasma and blood cells. After blood is centrifuged in centrifuge bottles at an appropriate speed and for an appropriate period of time, blood cells will precipitate at the bottom, and plasma will be located in the upper layer, facilitating easy separation and collection.
• Chemical Substance Separation:
  Centrifuge bottles also play an important role in the separation of mixtures in chemical synthesis. For example, in organic synthesis experiments, the reaction mixture may contain solid products and liquid solvents. By placing the mixture in a centrifuge bottle and centrifuging it, the solid products can be precipitated at the bottom, facilitating separation and purification. In the preparation process of nanomaterials, centrifuge bottles can be used to separate nanomaterials of different sizes. By adjusting the centrifugation speed and time, nanomaterials of different particle sizes can be layered and precipitated, thus achieving fractional separation.
• Environmental Sample Analysis:
  In the field of environmental science, centrifuge bottles are used to process environmental samples such as soil and water samples. Water samples collected from the field may contain suspended particles, microorganisms, etc. By centrifuging the water samples in centrifuge bottles, these components can be precipitated, facilitating chemical analysis of the supernatant part of the water samples or microbial detection of the precipitated part. For soil samples, centrifuge bottles can be used to extract organic pollutants or heavy metals in the soil. By adding appropriate extractants and then centrifuging, the target pollutants can be transferred to the extract solution for subsequent analysis.

3. Precautions for Use

• Balancing Issue:
  During centrifugation operations, centrifuge bottles must be properly balanced. This means that the weight of the centrifuge bottles and their contents placed in the opposite positions of the centrifuge rotor should be as equal as possible. If they are unbalanced, the centrifuge will vibrate violently when rotating at high speed, which may not only damage the centrifuge but also affect the centrifugation effect and even cause the centrifuge bottles to break and the samples to be lost. For example, when using two centrifuge bottles for centrifugation, it is necessary to ensure that the volumes and weights of the samples in the two centrifuge bottles are similar, and if the samples are liquids, the liquid levels should also be as close to the same as possible.
• Selection of Rotation Speed and Time:
  The rotation speed and centrifugation time of centrifuge bottles should be reasonably selected according to the properties of the samples (such as density, particle size, etc.) and the purpose of centrifugation. Excessively high rotation speed or overly long centrifugation time may lead to excessive compaction of the samples, making it difficult to resuspend or separate them; while too low a rotation speed or too short a centrifugation time may fail to achieve the expected separation effect. For example, when separating cell debris from intact cells, an appropriate rotation speed (usually between 1000 and 3000 rpm) and centrifugation time (such as 5 to 10 minutes) need to be selected according to the size and density of the cells to ensure that cell debris precipitates at the bottom and intact cells remain in the supernatant or the middle layer.
• Cleaning and Disinfection:
  Centrifuge bottles should be cleaned in a timely manner after use to remove residual samples and reagents. For reusable centrifuge bottles, disinfection treatment is also required after cleaning to prevent cross-contamination. The cleaning and disinfection methods vary depending on the material of the centrifuge bottles. Plastic centrifuge bottles can be cleaned with mild detergents, rinsed thoroughly with clean water, and then sterilized by autoclaving or soaked in chemical disinfectants; glass centrifuge bottles should be carefully cleaned to avoid scratches when being cleaned. Usually, they can be soaked in acid solutions to remove stubborn stains, rinsed thoroughly with clean water, and then sterilized by dry heat or moist heat.