Caleva design and manufacture a range Extruders and Spheronizers (marumerizers) from laboratory development to full scale production.
Wet Mass Extrusion-Spheronization
Spheronization is a rapid, economical and well understood method for making pharmaceutical spheroids. The Caleva extruders and spheronizers shown above are used in this process. Since extrusion is a necessary first step, this process is often referred to as the "extrusion & spheronization" process. The usual steps in the extrusion-spheronization process are described as follows:
- The powdered pharmaceutical ingredients are mixed and blended.
- Liquid binders are added to the mix to create a semi-wet plastic mass with the proper consistency for extrusion. The venerable "hand squeeze test" can be used to gauge the consistency of the wet mass, however, the Caleva Mixer Torque Rheometer (MTR) can be used to more accurately and consistently quantify the properties of the mix. The Caleva Datastor software can also be used to acquire and store extrusion and spheronization data (such as product temperature, RPM and power) from any Caleva datastor-enabled device for further analysis.
- The wet mass is put into an extruder and extruded to form a "spaghetti-like" extrudate. The diameter of the extrudate will be the approximate size of the final spheres.
- The extrudate is put into a spheronizer which converts the extrudate into small spheres.
- The spheres are dried and, if necessary, coated.
Hot Melt Extrusion:
Long used in the plastics industry, Hot Melt Extrusion (HME) is rapidly gaining popularity in the pharmaceutical industry. Hot melt extrusion is used for incorporating pharmaceutical ingredients into wax or polymer based matrices. HME is an effective and proven technique which avoids many of the problems associated with formulating pharmaceutical compounds, especially compounds that are poorly soluble in water.
Hot Melt Extrusion is a continuous process which utilizes either one or two screws housed in a heated jacket. The polymer is melted by the heated jacket and mixed with the Active Pharmaceutical Ingredient (API) by the screws which also forces it through the die, where the polymer cools and transitions back to the solid state. The extruder can be configured with multiple heating and cooling zones. Ingredients can be injected at multiple points along the length of the extrusion barrel, which is usually equipped with ports to accomidate sensors for monitoring the extrusion process.
HME is a very flexible process. Once optimized HME can achieve high production outputs and can be used for forming a variety of solid dosage forms, including tablets, transdermals, thin films and suppositories.
Advantages of spheronization
- Manufacture of modified, or controlled release formulations.
- Mixing of otherwise incompatible formulations.
- To enable uniform coating and accurate free flow filling into capsules. This application requires consistent smooth surface particles, with a narrow size distribution.
- Aesthetics. Small spheres can be an important marketing and product feature for pharmaceutical, food and cosmetic products.
- Elimination of dust. Spheroids can reduce risks due to toxic, environmental, and explosive hazards.
- To improve processing consistency and productivity by using consistent free-flowing spheres.
- To reduce product settlement in transport and handling.
Advantages of Hot Melt Extrusion
- HME, unlike traditional formulation processes, can be used for compounds that are insoluble or poorly soluble in water.
- HME is a continuous process. Heating, mixing and forming is performed continuously within the extruder.
- HME is very flexible. A wind range of forms, such as tablets, films and fibers can be made using HME.
- Fewer processing steps.
- Absence of solids.
- Improved bioavailability.