How Laboratory Homogenizers Support Medical Research

A visit to laboratories devoted to the development of new pharmaceuticals and pharmaceutical processing procedures gives an appreciation for the vast array of R&D equipment employed in new drug development. Among new drug development devices employed are sure to be found laboratory homogenizers  Lab homogenizers are the versatile benchtop tools that perform a wide variety of essential processing functions in medical research prior to ramping up to production scale operations.

Medical Research Lab Homogenizers Defined

First of all, the word “homogenizer” covers a broad range of processing techniques.  Most folks when thinking of homogenizing think of milk in the grocer’s case.  And in a way that is correct.  If not homogenized Bossy’s yield will separate into milk and cream, two relatively incompatible liquids.  (Think oil and water).

But lab homogenizers do much more than that.   Controllable-speed medical lab homogenizers offered by CAT Scientific are used to emulsify, disperse, mix and otherwise process various substances including liquids such as emulsions, slurries, and pastes as well as more abrasive media such as powders by using the power of the homogenizer generator.  With the right attachments they can provide in-line processing or with an analytical mill provide particle reduction with small sized samples.

Components of a Medical Research Lab Homogenizer

At CAT Scientific we describe med lab homogenizers as consisting of the power end and the business end.  These lightweight units consist of an electrically or air powered drive motor with controllable speed.  Some models such as the CAT X100D  are equipped with an LED display showing operating speed.  Drive motor selection is based primarily on the size and nature of samples being processed, power in watts  and drive motor speed capability.

Except for the small hand held CAT homogenizer  all drive motors should be clamped to an adjustable mounting platform.  This holds the drive motor and the generator assembly mechanism firmly in the flask or beaker and slightly offset to avoid creating a vortex.  Clamping the hand held unit in place is also a “best practice” to avoid potential mishaps if the operator’s attention  wanders.

Likewise, homogenizers should be immersed in the sample before being turned on, and speed should be controlled with a slow start to avoid splashing samples out of the container.

The Business End of a Medical Research Homogenizer

The business end of a medical research homogenizer is called the generator.  It is comprised of four components:

  1. a stationary tube firmly attached to the drive motor housing
  2. a rotor shaft passing through the tube and powered by the drive motor
  3. the rotor with sharply machined teeth designed for the task and attached to the rotor shaft
  4. the stator, which is screwed onto the stationary tube and with teeth machined to compliment the design of the rotor.

The base of the rotor works against complimentary machined sharp slots in the stator.  When operating the homogenizer generator draws the sample up into the rotor-stator assembly and violently propels it against and through the stator slots to perform the mixing, emulsifying and dispersing action.

Other Medical Research Homogenizer Selection Criteria

Generator assemblies, also called dispersing tools, come in different diameters and lengths and can be used to process samples from 0.1 ml to 20 liters in size.  Generator design is governed primarily by the substances being processed and the objective of the procedure.  Design is generally characterized to work with medium, low and fine viscosity materials.  Knife generators are used to shred fibrous biological materials for further analysis.  CAT dispersing tools are classified as V for viscous, N for low viscous, F for fine and K for knife.

Other Medical Processing Options

Coupling the homogenizer drive motor to a flow through chamber creates an inline processing system that performs the homogenizing action while transporting samples from one vessel to another – or back to the same vessel.  Two models are available from CAT Scientific.  The smaller DK30 chamber processes 2,000 to 3,000 liters per hour; the larger DK40 flow through chamber processes to 5,000 liters per hour and is equipped with a water-cooled jacket.  Sample dwell time in both units can be controlled by restricting the outlet tubes.

Particle size reduction is accomplished by coupling the AX60 analytical mill to the powerful X1000 homogenizer drive motor.  Stainless steel or carbide blades housed in a dust-tight upper and lower chamber quickly pulverize samples volumes up to 180cc for further processing.  To avoid potentially damaging heat to samples, the mill can be cooled with water or liquid nitrogen.

How to Clean and Maintain Medical Research Homogenizers

Cleaning and sterilizing rotor-stator generator assemblies is a must in all applications but particularly critical in medical and pharmaceutical applications.   The first step is removing residues by disassembly then rinsing components in water followed by carefully scrubbing them with a brush in a disinfecting solution.  Exercise care due to the sharp edges on rotors and stators.  Sterilizing can be accomplished in autoclaves at temperatures to 121⁰C and pressures to 15 psi for 60 minutes.  Follow the instruction manual for exact procedures and to avoid heat damage to bearings and seals in the shaft.

Please feel free to contact us for information on the use of lab homogenizers in the medical and pharmaceutical field, and for recommendations on the correct homogenizer model for your needs.

Posted in

Bob Wilcox

Bob Wilcox has represented CAT Scientific’s family of homogenizers, magnetic stirrers, liquid handling and related laboratory equipment since 2002 when Staufen, Germany-based CAT Ingenieurbüro M. Zipperer GMbH established operations in North America. Bob oversees CAT Scientific laboratory apparatus sales and service organization from the company’s headquarters in Paso Robles, CA. He also is in charge of the parent company’s line of JetCat jet turbines, turboprop, and helicopter power plants for hobbyists’ radio controlled fixed wing and helicopter model aircraft. -- Earlier in Bob’s career he was involved in visual and special effects as well as camera and electronics supervisory responsibilities for the motion picture and television industry.

Leave a Comment