Supplementary Materialspharmaceutics-11-00616-s001. single-step freeze-drying of low focus mAb formulations, while maintaining elegant lyophilisates and ensuring protein stability at the same time. = 3) standard deviation. Residual moisture of FS with 50 mg/mL mAb was generally higher compared to FCD, FCD/P/S, and FCD/S (Figure 5b). C1 resulted in a residual moisture for FS of 0.64%, while freeze-drying with C5 led to a residual moisture of 1 1.1%. FCD, FCD/P/S, and FCD/S with 50 mg/mL mAb showed low residual dampness degrees of ~0.2%, similar for C5 and C1 and like the values for the 10 mg/mL mAb formulations. The differing residual moisture degrees of 10 mg/mL FS when freeze-dried with different cycles had been reflected in various of 5 C was reported and Depaz et al. discovered a of 5C for the 50 mg/mL genuine sucrose formulation. For formulations including excipients that have a high can be less pronounced. For FCD/P/S and FCD/S both 10 mg/mL formulations demonstrated virtually identical Tg ideals, but their Tc differed by 2.6 C. This straight Atractylenolide III translated into different wedding cake appearance when freeze-dried using the same cycles with Tp near Tg (C1CC5). Tc depends upon several factors like the solid focus aswell as sublimation price. Thus, collapse in the vial might occur at slightly higher temperatures during freeze-drying than the Tc determined by FDM [33]. Greco et al. used optical coherence tomography to determine Tc of a 5% sucrose solution in the vial during freeze-drying and found it to be 3 C above that temperature determined by FDM [34]. This is in line with the cake appearance observed in our study. Fs at low protein concentration showed major dents when freeze-dried with the conservative lyophilization cycle, where Atractylenolide III Tp was close to Tc. Collapse occurred only when Tp was much higher than Tc, as it was the case for C1. In terms of internal cake structure, Atractylenolide III -CT analysis showed minor cracks in most lyophilisates independent of the cycle employed. Patel et al. suggested that cracks should not be considered cake defects as they are only process artefacts which are not detrimental to product quality [8]. In fact, internal cracks have been found to be a result of Atractylenolide III relieved stress during secondary drying, when unfrozen water is PDGFD removed [35,36]. Lam et al. suggested that the formation of splitted cakes might be linked to a complex interplay of events occurring during the freezing step. They reported the fact that incident of breaks is certainly extremely adjustable also, and noticed that cracks could be within lyophilisates that appearance pharmaceutically elegant from the exterior [37], consistent with our observations. Even more important are inner defects such as for example partial collapse, that was uncovered by -CT for e.g., 50 mg/mL FS when freeze-dried with C5. This highlighted furthermore the fact that dents noticed by visible inspection had been truly correlated towards the starting point of collapse. 4.2. Influence of Process Variables It is well-established that an boost of Ts during major drying reduces routine period [3]. Correspondingly, even as we elevated Ts during major drying from ?10 C to +30 C ultimately, we substantially shortened major drying out by 48%. Extra elimination of supplementary drying shortened the entire routine time by altogether 50%. Although.