Tightly controlled particle size reduction requires consistent, uniform, and effective pharmaceutical and nutraceutical end-products. After finishing research and developing new pharmaceuticals or supplements, pharmaceutical manufacturers need to identify the best way to deliver the active pharmaceutical ingredient (API) into a suitable dosage form. The importance of size reduction in pharmacy medications and supplements cannot be understated.

Flowability and ease of handling API (and fillers) are essential in determining how

 to formulate best and manufacture pharmaceutical products. Dissolution rates, uniformity, and consistency of the drug content are the most critical parameters for effectiveness, quality, and – most importantly – bioavailability.

What is Bioavailability and Why is it So Important?

Bioavailability measures the degree and rate at which the body absorbs a drug once consumed, so it plays a significant role in its efficacy. As manufacturers develop medicines for specific purposes, particle size can influence their effectiveness. Having particles that are too large or inconsistently sized can alter a medicine’s formula and how well it works within the body. Having particles outside the standard range can diminish outcomes and absorption rates, making the drug or supplement either less effective or potentially dangerous.

Another vital parameter involves the number and size of particles. There is but one diameter for perfectly spherical particles, while particles that are not uniform require multiple measurements to map their distribution.

With pharmaceuticals and nutraceuticals, standard practice is to rely heavily on the width of the distribution. During production, a manufacturer will set constraints around distribution width so that particles are sized appropriately for the product.

Types of Equipment That Reduce Particle Size


The wide rotors on full-screen hammermills accommodate multiple hammer arrangements, producing uniform granular grind. Prater’s hammermills produce ~40 mesh particle distributions and can deliver uniform grinding with less heat build-up.

Fine Grinders

Fine grinders are the ideal machines for the dry, free-flowing material used in pharmaceuticals and nutraceuticals and work well with particles as fine as 200 mesh (74 microns) with a tight distribution of particle size. Prater’s fine grinders offer greater capacity than others on the market and can be precisely configured to control particle size and distribution once finished. Features include replaceable grinding blades and sanitary construction, both critical factors in producing pharmaceuticals and nutraceuticals.

Air Classifying Mills

Air classifying mills grind particles down to sizes ranging from 50 mesh (297 microns) to particles smaller than a micron. Prater’s air classifying mill combines two-stage closed circuit grinding with internal air classification, offering unique capabilities that allow it to surpass single-pass mills for challenging to grind particles and those that require a narrow particle distribution. Additionally, Prater’s air classifying mills use an automatic door interlock for added safety, preventing access to the internal machinery during operation.

Lump Breakers

Lump breakers reduce pharmaceutical materials down into consistently sized particles, making them easier to handle. Machines running at slower speeds break down coarser or harder materials while reducing material into finer particles faster. Designed to provide more straightforward and efficient processing than its competitors, Prater’s lump breaker compacts material even further, allowing downstream machinery to handle it more efficiently, reduce downtime, increase performance, and improve product quality.  


Vibratory sifters conduct the final stage of pharmaceutical manufacturing, screening out larger particles so that the remaining particles are the requisite size. The sifted powder is then sent to the next manufacturing phase, where the powder is made into tablets or liquid suspension. Scalping products from a quarter-inch thick to 325 mesh (44 microns), Prater’s centrifugal sifters provide better throughput while also offering superior air purge, an adjustable 4-paddle rotor, easier maintenance, and self-cleaning capabilities. Prater’s mini-sifter allows easy assembly and disassembly, interlocked safety features, and a robust design for smaller operations.

Other forms of equipment used in particle size reduction include feeding and metering, classification, and screening/ separation. While each piece of these equipment types may vary, they are responsible for sifting, grinding, de-lumping, or compacting dry materials.

Why High Quality is Essential

Producing medications and supplements requires that manufacturers take great care to ensure the safety of their products. One of the best ways to do this is by using equipment built by Prater, who have carefully designed their machinery for reliability and easy cleaning and maintenance. For those who wish to learn more about our customizable mills, grinders, or separating equipment, contact Prater today.