The spray-dried gum also exhibited a significant (p < 0.05) higher WHC than the control, freeze-dried and vacuum oven-dried gums; while the control sample provided the lowest significant (p < 0.05) WHC among all samples (Figure 5a).
A lyophilization process is usually only specified in terms of a 'recipe' (shelf temperature and chamber pressure vs. time); according to the recent PAT guidelines issued by FDA, there is the need to develop in-line tools to enable better monitoring and control freeze-drying.
Detection of TRIM29: human skin obtained from superficial normal adult skin from plastic surgery were used as positive control: frozen sections were fixed in 4% paraformaldehyde (Sigma, Bornem, Belgium), followed by 3 washes in PBS glycin (0.1 mM, Merck, Germany).
Progenitor cell proliferation of control, frozen and thawed or freeze dried, and rehydrated cells was quantified by an in vitro method using MethoCult® Classic, a semi-solid methylcellulose system containing stem cell factor (SCF), GM-CSF, interleukin 3 (IL-3), and erythropoietin (StemCell Technologies, Vancouver, BC, Canada) and by measuring clonogenic activity via CFU.
The swelling behavior of the G-A-PAA and control freeze-dried hydrogels was investigated in ddw, at 37°C, using the conventional gravimetric method.
Total RNA was isolated from ependymocytes obtained by trypsynization of the ependymal surface with 0.25% trypsin and from fragments of brain tissue (positive control) frozen in liquid nitrogen.
Control freezing was carried out using stem cell culture medium (DMEM/F12 1:1) supplemented by SR and 10% DMSO which is the medium regularly used for the time being.
As positive control, frozen mouse tissue samples of right ventricles and kidneys were homogenized with a glass pistle in a glass potter.
Several processes have been developed on this principle, for example the Total Sprex process to remove (hbox {H}_2 hbox {S}) from natural gas (Mougin et al. 2008), Cryocell by CoolEnergy to remove (hbox {CO}_2) from natural gas (Hart and Gnanedran 2009), Controlled Freeze Zone by Exxon for sour gas fields (Burgers et al. 2011) and the Alstom anti-sublimation process (Clodic et al. 2005).
Nuclei suspension was then cryopreserved by addition of DMSO to 10%, controlled freeze to -80°C, and subsequently stored in liquid nitrogen.
