DrM, Dr. Mueller AG

DrM Group is a Swiss manufacturer of filtration and vibratory mixing equipment. For pharmaceutical and biotech manufacturers, DrM supplies single-use systems for cell harvest, clarification and low-shear mixing, alongside stainless steel candle filters and vibromixers designed for GMP production.

Swiss engineering for pharma and biotech processes

In pharma and biotech, mixing and filtration are rarely difficult on their own. The real challenge is doing them without damaging the product, opening the system or losing yield at the end of the batch, and then repeating the same result at a larger scale. DrM designs its filters and mixers around exactly these constraints. Each system is engineered for the customer’s product, batch size and regulatory requirements, and the same operating principle applies from the lab to commercial production.

Single-use filtration and mixing for biopharmaceuticals

In single-use facilities, cell harvest is often the step that breaks the disposable concept. Depth filter trains grow with batch volume and cell density, and centrifuges bring back cleaning and validation work. The FUNDALOOP® SU takes a different approach: a single-use candle filter that regenerates itself. After each filtration cycle, a patented back-flush removes the cake from the filter cloth, so one compact filter can work through the whole batch and handle primary and secondary clarification in a single step.

For mixing, the FUNDAMIX® SU replaces the rotating impeller inside the bag with a vibrating plate driven from outside. The result is homogeneous, low-shear mixing for media, buffers, formulations and cell or protein suspensions, with nothing rotating in contact with the product.

A FUNDAMIX® SU mixing bag is sealed in DrM’s own ISO Class 7 cleanroom, where single-use assemblies are produced from USP Class VI-compliant materials.

A FUNDALOOP® SU single-use bag with integrated filter candles is placed into its pressure vessel, ready for multi-cycle cell harvest and clarification without depth filters or centrifuges.

Two FUNDAMIX® packaged mixing units for GMP production: a mobile skid on load cells with integrated control cabinet, and a compact system with touch HMI and FUNDAMIX® Amplitude Controller.

Connecting the FUNDAMIX® SU drive to a single-use mixing bag: the vibratory drive stays outside the bag, so nothing rotates in contact with the product.

A single-use bag assembly with tubing, connectors and capsule filter is prepared for closed processing, ready to integrate with DrM’s single-use mixing and filtration systems.

A 50l FUNDAMIX® glass reactor unit with Amplitude Controller, used for process development and scale-up data, applying the same vibratory mixing principle as production systems.

DrM Group headquarters in Maennedorf, Switzerland, where filtration and vibratory mixing systems for pharmaceutical and biotech production are engineered, tested and manufactured, with rooftop solar supplying part of its electricity.

GMP stainless steel filtration and vibratory mixing

Insulin and other proteins can lose activity under aggressive agitation, yet the batch has to stay uniform until the last vial is filled. The stainless steel FUNDAMIX® vibromixer handles this by oscillating a perforated plate instead of spinning an impeller. There is no vortex, no need for baffles and no rotating mechanical seal, and the plate can sit close to the vessel bottom so mixing continues as the tank drains. All product-contact parts are CIP and SIP compatible.

Where solids need to be separated under GMP conditions, the STERIBAC® candle filter filters, washes, dries and discharges the cake inside one closed vessel. Its heel volume filtration step also recovers the liquid left in the vessel after the main filtration, so less product is lost.

From lab testing to commercial production

Every process behaves differently, so DrM recommends testing before scale-up. Engineers can run trials with their own product in DrM’s test facilities, or rent lab and pilot units for their own site, using the same principle as the production equipment. The results feed directly into the design of the full-scale system.

DrM then takes the project through engineering, fabrication, and factory and site acceptance testing, and supports the installation afterwards with training, field service and spare parts. For mixing, complete packaged units and skids with integrated CIP/SIP and qualification documentation are also available.

Quality and cleanroom manufacturing

DrM is ISO 9001 certified. Single-use assemblies are produced in DrM’s own ISO Class 7 cleanroom from USP Class VI compliant materials, with documentation available to support validation. Stainless steel equipment follows GMP and EHEDG hygienic design principles, and automated systems can be supplied with 21 CFR Part 11 compliant controls.

Global presence and local support

Headquartered in Maennedorf, Switzerland, DrM has subsidiaries in the USA, China, Poland, India and Malaysia, together with licensees, representatives and sales agents in other regions. Local teams support projects from the first discussion through commissioning and after-sales service.

About DrM Group

DrM was founded in 1982 by Dr Hans Mueller, an ETH Zurich engineer whose career produced more than 400 patented inventions, including the vibratory mixing principle behind FUNDAMIX®. Still family-owned, DrM has delivered more than 4,100 FUNDABAC® and CONTIBAC® candle filters to 85 countries and brings that filtration experience to its single-use and GMP portfolio.

To discuss your process with DrM’s engineers, please send an enquiry using the form above.