As a commonly used laboratory sample pretreatment equipment, the water bath nitrogen blower has certain requirements for the sample to ensure the smooth concentration process and reliable experimental results.

1、 The physical state of the sample

Liquid samples: mainly suitable for concentration processing of liquid samples. The sample should be a clear and transparent liquid, free of suspended solids or precipitates, so that nitrogen can evenly blow the surface of the sample and promote solvent evaporation.

Sample volume: The volume of the sample should be moderate, usually not exceeding 2/3 of the container, to avoid sample overflow during the concentration process. Meanwhile, the initial volume of the sample should be reasonably selected based on the concentration target and container specifications.

2、 Chemical properties of the sample

Solvent type: Suitable for handling samples containing organic solvents (such as methanol, acetonitrile, acetone, etc.) or aqueous solutions. For flammable solvents such as ether, they must be operated in an explosion-proof fume hood and ensure that the operating temperature is below the ignition point of the solvent.

Thermal sensitive samples: For heat sensitive samples such as proteins, vitamins, antibiotics, etc., a water bath nitrogen blower can perform gentle concentration treatment at lower temperatures to avoid degradation or denaturation of the samples due to high temperatures. For example, when processing biomedical samples, the water bath temperature is usually set at around 37 ℃.

Volatile samples: For highly volatile samples, the nitrogen blowing process needs to be carried out in a well ventilated environment to prevent solvent vapors from causing harm to the laboratory environment and operators.

3、 Sample container

Container material: The sample should be placed in a container compatible with solvents and nitrogen, such as glass test tubes, conical flasks, centrifuge tubes, etc. The container material should withstand water bath heating and nitrogen blowing to avoid chemical reactions with the sample or solvent.

Container specifications: Usually suitable for multiple sizes of containers, but it is necessary to ensure that the container can be securely placed on the sample rack. The outer diameter and height of the container should match the height of the sample holder and blowing needle of the nitrogen blower, so that nitrogen can evenly blow the surface of the sample.

4、 Sample processing precautions

Solvent displacement: If solvent displacement or stabilizer addition is required, mixing should be completed before nitrogen blowing to ensure the stability of the sample during the concentration process.

Sample protection: To avoid cross contamination, nitrogen blowing needles need to be replaced or cleaned between different samples. Using disposable glass test tubes or specialized concentration bottles can reduce cross contamination between samples.

Process monitoring: During the concentration process, it is necessary to monitor the liquid level drop of the sample in real time and manually adjust the blowing needle height if necessary. For thermosensitive samples, intermittent blowing or low-temperature concentration can be used to prevent sample loss.

In short, the water bath nitrogen blowing instrument has certain requirements for the physical state, chemical properties, container material and specifications, and processing of the sample. When using a nitrogen blower, it is necessary to select the sample container and set the operating parameters reasonably according to the specific properties and experimental requirements of the sample, and strictly follow the operating specifications to ensure the smooth concentration process of the sample and obtain reliable experimental results.