Water treatment: The water used for producing the hemolytic agent undergoes strict filtration using high-pressure reverse osmosis membranes to ensure that there are no particles larger than 0.2μm in the water. Ion exchange resins are then used to remove dissolved ions from the water, resulting in a water resistivity of ρ>10MΩ/cm.
Ingredient preparation: Strict adherence to the hemolytic agent's formulation is required to ensure its quality.
Mixing: The primary ingredient of the hemolytic agent is cationic surfactants, which have limited solubility in water and are prone to foaming and loss. Therefore, the mixing process is crucial. The specific procedure involves using a mixer with a motor speed ranging from 30 to 50 revolutions per minute and blades that are 1/3-3/5 of the diameter of the mixing tank. The process starts by adding dodecyl trimethylammonium chloride, stirring at a temperature of 30-70°C for 0.5-2 hours until it is mostly dissolved. Then, the temperature is lowered to 15-30°C, and tetradecyl trimethylammonium bromide is added. These two chemicals need to be fully dissolved and blended for at least 20 hours. Finally, potassium cyanide and other materials are added, with the stirring time for potassium cyanide kept relatively short, approximately 10-20 minutes.
Sterilization: Maintaining the long-term storage and usability of the hemolytic agent requires proper sterilization. Throughout the mixing process, cleanliness and aseptic conditions in the workshop should be ensured. After the mixing is completed and before filling, the agent should be exposed to ultraviolet light for 0.5-2 hours to achieve sterilization.
Filtration: Filtration is a crucial step to ensure the absence of insoluble impurities in the hemolytic agent and to meet the instrument's requirements for blank during usage. A three-stage filtration process is employed, with each filtration unit having a pore size of 0.1-0.3μm to ensure high-quality filtration.
Filling: Filling is the final step to guarantee product quality. High-quality imported plastic containers specifically designed for medical use should be chosen, ensuring they are free from impurities and contamination that could affect the reagent's blank. Before formal filling, the reagent should be used to rinse the entire filling system to ensure cleanliness and compliance with requirements. The use of automated machines for filling helps reduce manual contamination. After filling, the reagent undergoes quality testing according to quality management procedures. Once it passes the testing, it can be formally stored and prepared for distribution.
This method ensures both the quality and extended storage life of the hemolytic agent. Experimental results have shown that hemolytic agents produced using this method can be stored at room temperature and remain usable for up to two years, extending the shelf life of the hemolytic agent.
