The extrusion spheroidization machine is the core equipment for preparing microspheres in modern pharmaceutical industry. Through the two-step process of "extrusion spheroidization", it can efficiently produce spherical particles with uniform particle size and high roundness. Taking the preparation of traditional Chinese medicine microspheres as an example, this article provides a detailed analysis of the equipment operation process and key parameter control.
1、 Preparation before operation
1. Inspection of Extrusion Rounding Machine: Confirm that the connection between the extruder and the rolling machine is normal, and check whether the mesh aperture (usually 0.8-1.2mm) meets the target particle size requirements. Turn on the device and run it without load for 2-3 minutes to confirm that there is no abnormal vibration or noise.
2. Raw material pretreatment: Mix drug powder and excipients (such as microcrystalline cellulose and lactose) evenly according to the prescription ratio, and add an appropriate amount of adhesive (such as 25% ethanol solution) to make soft materials. The humidity of soft materials should be moderate, and it is advisable to hold them in a ball and let them disperse upon touch.
2、 Core operational steps
1. Extrusion process
① Parameter setting: Put the soft material into the extruder hopper, set the extrusion speed to 200-300rpm (adjusted according to the material viscosity), and control the pressure at 0.5-1.0MPa.
② Key points of operation: The soft material should be evenly filled in the hopper to avoid uneven density of the extruded material caused by local accumulation. The extruded material should be a cylindrical strip with a smooth surface. If there are fractures or bubbles, the amount of adhesive or extrusion pressure needs to be adjusted.
2. Rolling process
① Parameter setting: Transfer the extruded strip to the rolling machine, set the rolling speed to 800-1200rpm, and the rolling time to 3-5 minutes.
② Operation points: The inner wall of the rolling machine needs to be pre coated with a small amount of talcum powder to prevent sticking. After startup, the strip gradually rolls into a spherical shape under the action of centrifugal force and friction, and during this period, static adhesion can be reduced by intermittently spraying 50% ethanol.
3、 Post processing and quality control
1. Drying and screening: Transfer the wet pills to a tray and dry them in a 50-60 ℃ hot air circulating oven for 4-6 hours until the moisture content is below 5%. After drying, sieve (18-24 mesh) to remove particles that are too large or too small.
2. Quality inspection
① Particle size distribution: determined by sieving method, the qualified pellet particle size difference should be less than/plusmn; 10%.
② Roundness: Evaluated by the angle of repose (≤ 30°) and the critical angle of the plane (≤ 45°), the smaller the angle, the higher the roundness.
③ Fragility: Shake 2g pellets for 20 minutes, and the weight loss rate should be less than 1%.
4、 Maintenance and safety
1. Daily maintenance: After each use, disassemble the extruder screen and the rolling machine turntable, clean the residual materials with medical alcohol, and add high-temperature resistant lubricating grease to the gearbox.
2. Safety regulations: It is strictly prohibited to touch rotating parts during operation. In case of equipment failure, power must be immediately cut off and warning signs must be hung. When the equipment is not in use for a long time, it should be stored in a dry environment to avoid rusting of metal parts.
Through standardized operations and parameter optimization, the extrusion rolling pellet making machine can achieve industrial production of pellet preparation, providing reliable technical support for the development of drug sustained-release and controlled release formulations.
