Due to a diet higher in fats and oils, human serum typically
contains higher levels of lipids than serum from other sources.
Even after sterile filtration through 0.1mm filters, particles
remain suspended in solution that can aggregate and precipitate
as a result of subsequent freezing, thawing and/or
heat-inactivation. It is for this reason that we suggest
minimizing such temperature changes. The presence of particulate
matter does not indicate contamination of any sort, and does not
negatively impact the serum’s performance.