In situ freeze dryer is a crucial core equipment in modern biopharmaceuticals, advanced materials, and fine chemicals. Its biggest feature is that the sample does not need to be moved after pre freezing, and the entire drying process is completed directly in the original container and position.This "pre freezing drying integrated" design avoids the risk of contamination during sample transfer, making it particularly suitable for mass production and research and development of sterile preparations, advanced active pharmaceutical ingredients, and precious samples. Mastering its standardized operating procedures is crucial for ensuring product quality.

　　1、 Preparation before operation: Precision calibration of equipment and samples

1. Equipment inspection and cleaning:

① Confirm that the equipment power supply, compressed air (if pneumatic gland is required), and other connections are normal.

② Cleaning and disinfecting the sample chamber and all shelves to ensure no residue from previous operations is the primary step for aseptic operations.

③ Check the vacuum pump oil level and sealing ring integrity of the equipment to ensure its performance.

2. Sample preparation and setup:

① The sample (such as drug solution) should be divided into open sterile penicillin bottles or trays, and the device should be uniform with a thickness generally not exceeding 1cm to ensure drying efficiency.

② Place the container containing the sample precisely on the shelf of the freeze dryer, ensuring stability and sufficient contact with the shelf.

3. Set program parameters: Based on the thermodynamic properties such as eutectic point and melting point of the sample, preset key programs in the control system:

① Pre freezing stage: Set target temperature and insulation time.

② One drying (sublimation drying) stage: Set the shelf heating program, insulation temperature and time, and vacuum degree target. Remove free water at this stage.

③ Secondary drying (analytical drying) stage: Set a higher shelf temperature and maintain insulation for a long time to remove bound water.

　　2、 Core operating process: automation and monitoring

1. Start pre freezing: Close the cabin door and start the equipment. The shelf will quickly cool to the preset pre freezing temperature and allow the sample to freeze in place.

2. Vacuum pumping and sublimation: After the pre freezing is completed, the equipment automatically starts the vacuum pump to reduce the pressure inside the cabin to the set value. Subsequently, the shelf slowly heats up according to the program, providing energy for the sublimation of the ice. The moisture in the sample sublimates directly into water vapor in the form of ice and is captured by the condenser.

3. Online monitoring and endpoint determination:

① Pay close attention to the curve changes of shelf temperature, sample temperature, vacuum degree, and condenser temperature.

② Professional models are equipped with a pressure rise test (PRT) function, which can automatically interrupt shelf heating at regular intervals and monitor the rate of pressure rise. It is a reliable method for scientifically determining whether each drying stage has ended.

　　3、 End operation and subsequent processing

1. Breaking and sealing (if applicable):

① After drying, first release ice (defrost) to the condenser, or slowly break the vacuum by introducing sterile dry nitrogen/air.

② For penicillin bottle samples, the bottle stopper can be automatically pressed in place by a capping mechanism under vacuum or inert gas environment to ensure that the sample is in a sealed and sterile state.

2. Sampling and recording:

① Slowly open the cabin, promptly remove the dried products, and immediately seal the packaging to prevent moisture absorption.

② Complete printing and saving of all process curves and parameter records for this run is the core requirement to meet GMP standards and quality traceability.

3. Equipment maintenance:

① Clean the cabin and shelves, and drain the defrosting water.

② Regularly inspect the vacuum pump oil, sealing ring, and refrigeration system, and perform preventive maintenance according to the plan.

　　Safety and performance tips:

1. It is strictly prohibited to forcefully open the cabin door during equipment operation.

2. Sample formula and process development are the foundation, and unreasonable freeze-drying formulas cannot obtain ideal products even with advanced equipment.

3. Complete system validation (IQ/OQ/PQ) is a prerequisite for ensuring its use in compliant production.

By following this guide, you will be able to safely and efficiently apply in-situ freeze-drying technology, providing solid support for your research and production.