Factors to consider when choosing a laboratory freeze dryer

Factors to consider when choosing a laboratory freeze dryer
1. The choice of the manufacturer.
Give priority to powerful laboratory freeze dryer manufacturers, and have many years of professional experience in the production of laboratory freeze dryers and professional technology, support for non-calibration, solutions.
2. Cold trap temperature.
Cold trap is a device used to trap steam between the freeze drying chamber and the vacuum pump. The lower the temperature of the cold trap, the stronger the trapping ability of the cold trap, but the lower the temperature of the cold trap, the higher the cooling requirements, and the relatively higher the cost of the machine and the operating cost.
The cold trap temperature of laboratory freeze dryer mainly has three grades of -50 ℃, -60 ℃ and -80 ℃. The laboratory freeze dryer with a cold trap temperature of -50 ° C is suitable for the lyophilization of water solvents or products whose freezing point is above -40 ° C. The experiment of the influence of the cold trap temperature on the water-capturing ability shows that the temperature of the cold trap drops from -35 ° C -50 ℃, the water-capturing ability is obviously improved, and the temperature of the cold trap is lower than -50 ℃, the water-trapping ability of the cold trap is not obvious. Therefore, if there is no special requirement, the temperature of the cold trap is -50 ℃. The laboratory freeze dryer with a cold trap temperature of about -80 ° C is suitable for the lyophilization of most products such as those containing organic solvents or some special products.
3. The amount of ice condensation.
The amount of steam trapped by the cold trap is related to the total sublimation of water or other solvents in the laboratory's daily experimental operation samples.
4. Extreme vacuum
The ultimate vacuum degree reflects the leakage of the laboratory freeze dryer and the pumping efficiency of the vacuum pump. The vacuum degree of the experimental operation should be within a reasonable range. The vacuum degree is too high, which is not conducive to heat transfer, but the drying speed is reduced.
5. Control display system
Laboratory series of laboratory freeze dryers are mainly used for the freeze-drying of materials, small batch production, and freeze-drying process condition tests. The control system must have real-time display of freeze-drying process parameters, such as cold trap temperature, vacuum degree, phase time and total process time; set, modify and effectively execute freeze-drying process procedures; good communication interface for easy data collection and storage .
6. Freeze-drying methods and functions.
Depending on the specific sample, there are different options for lyophilization. The common laboratory freeze-drying experiments all adopt the Process B method, that is, freeze-drying in the freeze-drying chamber or hanging the bottle for freeze-drying. Also choose the capping device; if it is a lyophilized bottle, you must choose a multi-manifold, suitable for round-bottom flasks, wide-mouth filter bottles or ampoules, but pay attention to whether you need to choose the appropriate adapter to use in combination; if the user The samples involved in the test include both lyophilization in the cavity and lyophilization of the external bottle, and a lyophilization cavity with an external port can be selected.
Different experiments and different samples have different requirements for the functions of laboratory freeze dryers. Generally speaking, for the freeze-drying of samples such as food, Chinese herbal medicines, powder materials, etc., it is generally recommended to use shelf-type laboratory freeze dryers; You must choose a laboratory freeze dryer with a capping device; it is recommended to use a hanging bottle type for the freeze-drying of microbial strains and be sure to choose an ampoule adapter for freeze-drying; if you want to do a freeze-drying process curve study, you must choose The controller can support eutectic point test equipment and software.