In addition to being popular in the food industry, freeze dryers also play a critical role in pharmaceutical manufacturing. They play the most important role – improving the stability and shelf life of pharmaceutical products. As a leading pharmaceutical equipment supplier, SED Pharma has also been providing a series of advanced freeze drying solutions in this regard.
Freeze drying removes water from drugs, allowing them to retain their biological structure and remain effective. The freeze drying process is often used for sensitive drugs, vaccines and biologics.
What Are the Basic Principles of Lyophilization?
Freeze drying technology, as the name implies, includes two main steps: freezing and drying. We have published an article called “What is freeze dryer“, you can go to the introduction of freeze dryers. The application of freeze drying technology in the pharmaceutical industry is also inseparable from the ultimate goal: to preserve drugs, make their transportation more convenient, and extend the storage time.
From physics, we know that water has three phases, O point is the common point of the three phases, and OA is the melting point of ice. According to the principle that pressure decreases and boiling point decreases, as long as the pressure is below the triple point pressure (the pressure in the figure is below 646.5Pa and the temperature is below 0℃), the water in the material can be sublimated directly from water to water vapor without passing through the liquid phase.
We can simply understand lyophilization from these aspects:
Screening of Freeze-dried Prescriptions
Before studying the freeze-drying process, it is necessary to conduct a thorough study of the raw materials, auxiliary materials, etc. For example, try to choose a freeze-drying protectant with a higher eutectic point to facilitate the smooth progress of the sublimation stage, shorten the freeze-drying time, and choose suitable antioxidants and acid-base regulators to ensure the stability of the product.
Pre-freezing
When freeze-drying, the product needs to be placed in a suitable container and then pre-frozen before sublimation drying. The pre-freezing process is not only to protect the main properties of the substance, but also to obtain a reasonable structure of the freeze-dried product to facilitate the sublimation of water. Pre-freezing is a very important step in the freeze-drying process, so three factors should be determined before pre-freezing: the lowest pre-freezing temperature, the pre-freezing speed and the pre-freezing time.
Sublimation Drying
When the frozen product is placed in a sealed vacuum container and heated, the ice crystals will sublime into water vapor and escape, thus dehydrating and drying the product. Drying starts from the outer surface and gradually moves inward. The gaps left after the ice crystals sublimate become escape channels for the sublimated water vapor. The interface between the dried layer and the frozen part is called the sublimation interface. When all the ice crystals are removed, sublimation drying is completed, and about 90% of the water can be removed.
Analytical Drying
Desorption drying is also called the second stage drying. The first stage drying removes water in the form of ice crystals, but the adsorption energy of adsorbed water is high. If sufficient energy is not provided, water cannot be desorbed from the adsorption. Therefore, the temperature of the product in this stage should be high enough, as long as it does not exceed the maximum allowable temperature, does not burn the product, and does not cause the product to be overheated and denatured.
Freeze-drying Endpoint
The determination of freeze-drying endpoint is an important step in process optimization. Accurately determining the freeze-drying endpoint can not only save energy, but also help control the final water content of the product and improve product quality. There are several main methods for determining the freeze-drying endpoint: pressure detection method, temperature detection method, weighing method, and Karl Fischer detection method.
What Are Applications of Lyophilizer in Pharmacy?
In the long-term development of pharmaceuticals, the preservation of drugs has always been a major problem. Applying vacuum freeze-drying technology to pharmaceuticals and conducting proper drug management can greatly improve the preservation conditions of drugs and the storage environment of drugs, which is of great significance to the advancement of pharmaceutical technology at this stage.
Chinese Medicine Preparations
Freeze-drying machine has also been increasingly used in traditional Chinese medicine preparations, especially in maintaining the stability of freeze-dried powder injections, solving the problem of unstable administration of some traditional Chinese medicine compound or single prescription in clinical practice. The characteristics of freeze-dried products are loose texture and rapid dissolution after dilution with water. For example, freeze-dried powder injections made from ginkgo leaf extract have been placed under high temperature and high humidity conditions for 10 years. In a few days, the results showed that there was no significant change in all test indicators.
In addition, vacuum lyophilization and freeze drying technology is the best solution to enhance the stability of liposomes and reduce adverse reactions to a certain extent. For example, making pueraria total flavonoids nanosuspension into freeze-dried powder can significantly improve its solubility, stability and bioavailability. Similarly, making cantharidin into liposome freeze-dried powder has a loose structure, uniform color and excellent rehydration performance. However, the freeze-drying process will destroy the liposomal phospholipid bilayer, so a suitable freeze-drying protective agent must be selected.
Biological Pharmaceuticals
What kind of biological preparations need to be freeze-dried? For example, antibody drugs, antibody-drug conjugates and vaccines.
For antibody drugs, freeze-drying can reduce the moisture content in antibody preparations, thereby reducing protein degradation, improving stability, achieving non-refrigerated storage and handling, and significantly extending the shelf life of antibodies.
Vaccines may undergo a variety of physical degradation pathways (such as denaturation, unfolding, aggregation, precipitation and adsorption) or chemical reactions (such as oxidation, deamidation and hydrolysis) in liquid preparations and become unstable, seriously affecting the efficacy of the vaccine. Therefore, removing moisture through freeze-drying can inhibit or intervene in these pathways to increase the stability of attenuated viruses, bacteria or other antigenic components, in order to extend the shelf life and improve storage stability.
Explore Quality Freeze Dryer at SED Pharma
SED supports advanced technologies in the field of pharmaceutical freeze drying, such as our SED-FDG-B pharmaceutical freeze dryer. In addition to its powerful production capacity, this equipment is designed for freeze drying of drugs, pharmaceuticals, and biopharmaceuticals. It offers a total usable shelf area ranging from 1.1 to 51 square meters to accommodate various production scales. In addition, SED-FDG-B complies with various international production standards and has a sturdy structure, adding more possibilities to your pharmaceutical production.
If you are looking for freeze dry machine for drug development and research with smaller production runs, the laboratory-grade SED-XDG Series can be one of your excellent choices. This series of freeze dryers is designed with accurate and versatile operation systems and structure, able to meet the special needs of pharmaceutical laboratories. With a user-friendly interface and advanced technology that enables researchers to easily control and monitor the freeze-drying process. Leave us questions now, we will have experts solving one by one.
Experience Yourself in Our USA Showroom
SED Pharma has opened a new branch office in San Bernardino, California. This expansion will allow us to better serve our customers throughout North America. The new office features a showroom that showcases its main products, including capsule counting lines and freeze dryers, and some of the equipment is already on display in the showroom. In addition, SED Pharma plans to provide services such as machinery financing, training, installation, maintenance, and spare parts sales at this location with price match guarantee. For more details, you can visit our announcement page.
