Silverson Machines

Silverson Machines specialises in the design and construction of high quality, high shear mixers for the processing and manufacturing industries worldwide

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When making a pharmaceutical cream or ointment a fine, stable emulsion with good dispersion of Active Pharmaceutical Ingredients (API) is essential for creating the right consistency and functionality in the end product.

A Silverson mixer can easily create a homogeneous, stable emulsion with a droplet size of 2 to 5 μm. Finer emulsions can be obtained depending on the formulation. The High Shear mixing action of a Silverson rotor/stator mixer can rapidly disperse API and other ingredients in the formulation.

Silverson is a pioneer in the development of Ultra hygienic, sanitary mixing equipment for the Pharmaceutical industry, which meets or exceeds all guidelines set by the regulatory bodies.

For low to medium viscosities, we recommend a Batch mixer for smaller volumes. For higher viscosities mixes, a High Shear Bottom Entry mixer with scraper/stirrer to maintain uniformity in the vessel. For larger batches, a Silverson In-Line mixer recirculating the contents of the vessel will produce a fine, homogeneous emulsion.

Silverson has been a pioneer in the design and manufacture of a new generation of Ultra Sanitary mixing equipment specifically aimed at the pharmaceutical and biotechnology industries.

With more than 60 years’ experience supplying pharmaceutical companies from the global leaders to small highly specialised companies, Silverson has an unrivalled knowledge of the particular requirements of pharmaceutical applications and regulatory bodies such as FDA, 3-A, cGMP, etc. Our standard mixers offer a high level of sanitary construction and for more advanced requirements we offer a range of specially designed Ultra Sanitary mixers and have the flexibility and capability to custom build equipment where required to meet your exact mixing requirements.

Creams & Ointments

Pharmaceutical cream or ointment is used as a means of delivering an active ingredient directly to the required area of the skin. Products can be either a water-in-oil (w/o) or oil-in-water (o/w) emulsion, consisting of waxes, emollients and lubricants dispersed in an oil phase, and a water phase containing emulsifying, stabilising and thickening agents, preservatives and in some cases, colorant. Active ingredients are dispersed in either phase or added when the emulsion has been formed and allowed to cool.

Manufacture of pharmaceutical creams and ointments presents a number of challenges; a Silverson mixer can rapidly disperse solids into liquids, hydrate thickening and stabilising agents, break down agglomerates and finely reduce particle and globule size to form stable emulsions and suspensions. Mixing times are dramatically reduced, while product uniformity and consistency are greatly improved. To learn more about this application, please read the report here.

Ophthalmic Solutions

Silverson Machines

Contact lens solutions and ophthalmic solutions have a similar base formulation—a saline solution (typically 5 percent) with a range of added ingredients, according to the desired function, which may include thickening agents, surfactants and active ingredients.

To blend these ingredients together, a mixer must provide vigorous in-tank movement to incorporate light powders that tend to float, and to prevent salt granules from sinking to the bottom of the vessel. There is also a need to properly disperse, hydrate and solubilise ingredients for optimal functionality. Processing must be carried out under a hygienic environment. A Silverson high shear mixer can rapidly dissolve salts and active ingredients and can hydrate stabilising agents in a fraction of the time taken by conventional mixers, and offers the highest standards of hygienic construction available. For more information about this application, please read the report here.

Pharmaceutical Syrups

Silverson Machines

Cough mixtures are typically formulated as a syrup at 60 to 75 percent concentration, made from sucrose, maltodextrin, glucose, invert syrup, etc. The remainder is made up of thickening agents, stabilisers and active ingredients.

A Silverson high shear mixer can produce 66 percent sucrose syrup at ambient temperature, offering considerable savings in process time and energy costs. For more information on this application, read the report here.

Sterile Processing

Silverson Machines

In response to the rigors of the pharmaceutical market, there is an increasing need for hygienic construction in process equipment. When processing products under sterile or clean room conditions – for example injectables and vaccines – there are different challenges, especially regarding product sterilisation. Mixing would typically occur before sterilisation, but in some instances this is impossible, which places further restrictions on the mixing process.

Silverson has pioneered the concept of “Ultra Sanitary” mixing equipment and has developed a range of Ultra Sanitary mixers designed for CIP and SIP, suitable for pharmaceutical and biotechnology applications, including processing of sterile ingredients. Silverson mixers comply with FDA, cGMP and 3A standards. For more information about this specialised application, please read the report here.

Tablet Coatings

Silverson Machines

Pharmaceutical tablet coatings generally consist of a sugar or cellulose based binder, plasticiser, film-forming agent and colorant. These ingredients are supplied in granulated or powder form for dispersion in aqueous or organic solvents at concentrations varying from 10 to 20 percent depending on the desired properties and formula.

With a Silverson high shear mixer the ingredients are quickly dissolved and dispersed, resulting in a uniform dispersion in a fraction of the time taken by conventional mixers. For more information about this specialised application, please read the report here.


Silverson Machines

Vaccines typically consist of an active ingredient suspended in a mixture of proteins and other organic compounds in a liquid base, usually water (wfi – water for injection).

As a pioneer in the field of “Ultra Sanitary” mixing equipment Silverson has an extensive knowledge of the challenges involved in the manufacture of vaccines, injectables and other biotechnology applications. We have supplied mixers for preparation of vaccines including influenza, meningitis and yellow fever as well as animal health applications such as foot and mouth disease (FMD). We can custom build equipment to the most exacting of standards including cleanroom operation. We can also provide documentation packages conforming to FDA, 3-A, cGMP and other guidelines and assist with the validation process. Whatever your mixing requirements, we can provide a custom-built solution.

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