Why do I notice particulate matter in some human serum?
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.