Moreover, the stability of HYAL-Psomes in the presence of Tryp was studied after 1 h of incubation (the final incubation time is longer due to the sample analysis time) was studied by AF4-LS, the conformation plots and apparent density for Empty-Psomes and HYAL-Psomes are shown in Figure and. In presence of 25 μg mL -1 Tryp after 1 h of incubation, no changes are observed for HYAL-Psomes. Thus, AF4 measurements additionally confirm the previous results of the stability experiments that the Psomes offer protection of the enzymes in presence of Tryp. The same study was carried out for MMPsomes (Figure ), slight changes in the apparent density are observed for MMPsomes, where the apparent density slightly increases. This can be either due to an increased molar mass caused by the formation of smaller aggregates or due to a decreasing volume of the MMPsomes due to the potential start of degradation processes of MMP1 by Tryp.