On average, four out of five Americans are prescribed antibiotics each year. (1) This equates to nearly 255 million people using a single pharmaceutical product, and does not take into account the many other products being used on a regular basis! To maintain consistent product availability, pharmaceutical manufacturers must have optimized mixing processes to achieve timely and efficient production. Following is a compilation of factors that can be adjusted on most homogenizers, which can optimize the mixing process and ultimately the product that will go to market.
Products tend to yield better results when heated prior to mixing; this is largely due to the effects of elevated temperature on viscosity, surface tension, and ability to aid the emulsification process. However, some products may actually fare better from pre-cooling; the optimal temperature is product-specific and should be tested in trial runs before experimentation.
Reverse Flow vs. Parallel Flow
Reverse flow confers product-on-product shear and allows for more impact, which is optimal for disruption of cells with thick walls that are not easily penetrated. Parallel flow, on the other hand, confers product-on-equipment shear, a shorter process, and less impact so as not to disrupt intracellular components. Additionally, parallel flow provides less shear than reverse flow.
Most homogenizers offer either pattern; although both EC setups should produce good results, one might yield better results depending on the product and application. When you first run a product through the homogenizer, try it both ways to see which provides a better outcome.
Reduced particle size is a measurable and successful outcome of the mixing process; increased operating pressure typically equates to decreased particle size. High quality homogenizers, such models produced by BEE International, can achieve a maximum operating pressure of 45,000 PSI.
Number of Passes
Multiple homogenizer passes are frequently employed to achieve complete cell disruption and/or smallest possible particle size; case studies have shown that with each pass, a smaller particle size is achieved. (2) BEE International homogenizers are among few on the market that can achieve particle sizes of 0.1 µm after only one pass.
Whereas elevated temperatures are recommended for pre-mixing treatment, when mixing has concluded the product temperature should be reduced immediately. This step is in place largely because elevated temperatures are detrimental to product stability; as such, some homogenizers contain a heat exchanger to quickly reduce temperature after mixing.
When you are ready to mix a product for the first time, run a few trials first. Determine what you are looking for: Smallest possible particle size? Disruption of a thick-walled cell? Then make adjustments to each of the above factors to identify the combination that will give your product optimal results.
Do you have a product that requires mixing but don’t have the proper equipment? BEE International Technology offers homogenizers with the ability to adjust all 5 factors in this post, which will help your lab produce nano/micro emulsions, dispersions, and suspensions. Visit us here to learn more about our products.