Why are liquid solution products more expensive than powder?

Why are liquid solution products more expensive than powder?
January 30, 2020 admin

Besides the additional labor, materials and packaging, solutions also require additional quality control procedures. For comparison, to analyze a powder product, you only need a single sample sent out for analysis, even if the batch is 10kg+, provided the batch is uniform and the sample is representative of the whole.

To verify a solution product you must measure both the concentration and the uniformity. This can be done by sampling the mixing vessel before bottling or by sampling individual bottles. We do the former, though in the past we did the latter. Both are acceptable according to cGMP, however we prefer the former because of the greater certainty it gives us about what goes into each individual bottle.

When sampling a mixing vessel you must take samples at different locations in the vessel and then each must be within the acceptable error bound (±10%) of your expected average concentration. When sampling bottled products you must sample a sufficient number of them that you have statistical confidence in the sample mean – this usually means about 3 samples per 1000 bottles. The latter is more expensive and less certain.

In addition to verifying concentration and uniformity, we also audit our finished inventory and send randomly selected finished products out for analysis.