Knowledge Base

Components were mixed with a specialist Caleva mixer to form a homogeneous paste

… Then the wet mass was extruded immediately with a radial extruder (Model 20 Extruder, Caleva Ltd, UK) that was fitted with a screen of 150 mm in diameter and 1.0 mm die holes. The extruder screen rotated at 30 rpm. After …

The different states of agglomeration were identified by the evolution of rheological properties under water addition and shearing conditions using a Caleva^®mixer torque rheometer.

Many experts recognise Caleva as a leading manufacturer in extrusion and spheronization equipment for the development of pharmaceutical formulations, catalysts and ceramics. However, the broard scope and flexibility of Caleva equipment provides diverse capabilities that is leading to emerging applications in implant manufacture and conservation science. To explain more, we caught up with Dr Anton...

Abstract: Spheronization is a rapid process for production of microspheres. The process involves the dry mixing of drug with microcrystalline cellulose (MCC), which on subsequent wetting with water forms a plastic mass suitable for extrusion and spheronization. As in any pharmaceutical operation, large number of factors may affect the production of pellets, which can be related to formulation or...

Thanks to Caleva not only for making great equipment but also for being helpful to give us access to it within our budget. I would ALSO like to thank Caleva for the help given in providing the small scale extrusion and spheronization equipment for our laboratory. The latest research paper from our pharmaceutical department (Lipids bearing extruded-spheronized pellets for extended release of...

The MTR-3 uniquely offers a means of characterising the rheological properties of a wet granulation by providing a quantitative value of the consistency of the material tested. The more traditional hand squeeze test, previously widely used, to measure or compare granulations, is falling into disrepute and is no longer considered appropriate for modern day industrial production or research...

One of the strengths of the Caleva Mixer Torque Rheometer (MTR-3) is that it can be used to verify the properties of wet powder mass samples taken during production in large scale mixer/granulator systems.

Caleva worked closely with a well known producer of food supplements made from natural materials, plant extracts and other natural food sources.  Their tablet formulations work well and this nutraceutical company has a good reputation for their products.  Generally they do not encounter problems with tablets breaking or disintegrating during manufacture, packing or storage.

Spheroids are popularly used in the design of multi-particulate drug delivery systems. Extrusion and spheronization is commonly employed to manufacture spheroids in the pharmaceutical industry. It is a multiple-step manufacturing process which could be summarized into the flow chart as shown in Figure 1.

In the mid 1990’s, the field of pyrotechnics was limited mainly to applications in aircraft ordnance, fireworks and rock blasting. This has been developed to a highly advanced science and is an extensively used technology which finds application in spacecraft, aircraft and underwater vehicle systems. “Pyrotechnic “is defined as “explosive-actuated” and refers especially to devices in which...

A company wished to move a formulation currently undergoing product development from small scale laboratory (with batches of 50 grams) to the next stage for a larger scale batch trial of 100 kg (scale–up).  The development had been started using a small Caleva Multi Lab bench top mixer (maximum batch capacity 50 gram of wet mass). This development had been successful and now additional samples...

During production scale extrusion heat is generated as a result of the process. The amount of heat generated will vary depending on:

• The formulation of the product
• The rate of extrusion
• The physical specifications of the extruder
• The type of extruder being used, for example, screw, gear, or basket.

Over the past couple of years I have worked with a huge number of chemical engineering teams, trying to crack the optimum base for a catalyst pellet. After hours of trials and research, I am pleased to say, we’ve done it!

OK, so this was a tip I discovered a while back, but now it’s becoming more and more beneficial for me in practice when working with sticky, viscous materials.  Perhaps this will help you too?

It is well established and understood that one of the most important factors in the development of a formulation for both tableting and making pellets by extrusion and spheronization is the amount of liquid binder added to the formulation. What is less widely acknowledged is the importance of mixing and the mixing regime used.