Is there a guide to the optimum Length to Diameter ratio of the extrudate fragments?
In the calculations used to demonstrate the data it is assumed that the extrudate is an infinitely long strand. In this case the length of the extrudate has no influence on the data shown. In reality, extrudate is not infinitely long and as the individual strands of the extrudate produced become shorter, the...
Variable Mix Time Test
It is well-known that a minimum amount of mixing is required to ensure consistent and repeatable product characteristics. What is often less considered is the possibility of over-mixing the product so that the characteristics of the resulting formulation undergo a change.
A direct consistency measurement of a small sample (generally around 40 g) taken from a process as it is ongoing. This allows for accurate comparisons to be made quickly, accurately, and repeatable way.
Multiple Addition Test
Binder liquid is added to a dry powder mix and the consistency is measured as the mixing and addition of binder progresses.
The consistency of the mix is measured at regular periods so that the relationship between the amount of liquid binder added to the mix and the consistency in the resulting formulation can be accurately shown.
All extrusion processes require the generation of pressure within the material to be extruded. When materials are put under pressure heat is generated. This cannot be avoided but different extrusion types generate different amounts of heat. There are basically three different types of extruder and the one chosen may have far reaching implications on production operations. It is important that...
A list of suggested uses for pellets in pharmaceutical applications.
We are working closely with many partners in a wide variety of industries as well as pharmaceutical. The industries where we are helping our customers to make pellets and extrudates are listed below.
The Caleva MCD was originally designed for coating of very small batches of tablets. The original Mini Coater Drier was very efficient at this. However, as a response to several user comments and requests a new version was designed to allow users to also coat small samples of pellets over a range of industries. The original improved design specification that users were requesting was that...
Extrusion and spheronization is not always completely straightforward. A formulation required for spheronization needs to go through the following processes and achieve the following properties.
Wet Granulation - Granules are formed by the addition of a granulation liquid onto a bed of powder under the influence of an impeller. This is typically carried out using a high-shear granulator or a simpler planetary mixer.
There are two main ways to make small pellets for drug delivery:
- Drug layering onto inert starter (or seed) pellets that are bought commercially
- Extrusion and spheronization binding the active material in the substrate of the pellet from the beginning
There is no right or wrong way to make pellets. The most appropriate method for your particular application will depend on what you are trying...
Our general tablet coater literature describes the coating capability of a tablet size of up to 10 mm. However, this refers to a diameter rather than a capsule style design in length. The Mini Coater Drier is incredibly versatile and really the limiting factor is generally a weight issue as opposed to size. It’s important to consider weight/batch size to ensure a good coating motion within the...
We always offer our potential users the opportunity to test their formulation with us in our lab. This is to ensure that installing our machines would be the right decision for their formulation development, and/or their production environment.
This short article has been written from notes that Dr Steve Robinson made during trials with catalysts sent to us by a customer and we achieved some...
We have been asked by a manufacturer (interested in looking at the development of Omeprazole formulations) if it was really necessary to coat these pellets with an enteric coating.
Product yields (the percentage of the spheroids produced in a batch that are within the size range required) will never be 100%.
We recently had a visitor from Asia who was trying to solve a problem with their cosmetic formulation. The investigator wished to have approximately 1 mm diameter pellets. The formulation presented was a tough, waxy material in irregular broken blocks that were up to about 10 mm in diameter and was unable to be spheronized into the required size or shape.
We are often asked if parameters used for film coating of materials in the Mini Coater Drier can be used for “scale up” to production. The desire for a process to be scalable is understandable but it is not always feasible or relevant.
In some circumstances it is possible to omit the extrusion stage, but the results may not be what you need.
It is dependent on what you need to achieve with your result and what you want to do in the next phase of the project. Whether or not you decide to include the extrusion stage will depend on what you want to achieve with your project.
At Caleva we are known for our expertise in helping our customers in the pharmaceutical industry with extrusion, spheronization, and making pellets.But we can also help with tabletting projects !The Caleva Mixer Torque Rheometer (MTR) is widely used to measure the characteristics of a wet granulation to establish the correct endpoint and mix time for any given formulation.The experiments and...
In many cases the main reason for the use of pellets in the manufacture of products is for its controlled release properties. However there are reasons to believe that pellets or spheroids in any case can offer a superior therapeutic effect even when modified release is not the prime objective.