AbstractBackgroundEffective cryopreservation allows for the long-term storage of living cells or tissues with the possibility of later clinical applications. Unfortunately, no successful investigations on the long-term preservation of adipose aspirates for prospective autologous fat grafting have been conducted.ObjectivesIn this study, we aimed to compare 3 different freezing methods to preserve adipose aspirates obtained from conventional lipoplasty to determine the optimal cryopreservation technique.MethodsTo determine the optimal cryopreservation technique, hematoxylin and eosin staining, MTS assay, and Annexin assay were performed on each of the 3 groups plus a fourth control group. Group 1 served as the control, and fat tissue was analyzed immediately after adipose harvesting with no cryopreservation. For experimental Group 2, 15 mL of adipose aspirates were directly frozen at −80°C for up to 2 weeks. For experimental Group 3, 15 mL of adipose aspirates were frozen inside the adi-frosty containing 100% isopropanol and stored at −80°C for up to 2 weeks. For experimental Group 4, 15 mL of adipose aspirates were frozen with freezing solution containing 90% fetal bovine serum (v/v) and 10% dimethyl sulfoxide (v/v).ResultsThe results demonstrated that the experimental Group 3 had significantly more live adipocytes and greater cellular function of adipose aspirates than the experimental Groups 2 and 4.ConclusionCryopreservation with adi-frosty containing 100% isopropanol appears to be the best means of cryopreservation of fat.Level of Evidence: 3