Trehalose glass

Mei, E, Tang, JY, Vanderkooi, JM, and Hochstrasser, RM, Motions of single molecules and proteins in trehalose glass. Journal of the American Chemical Society 125 (2003) 2730-2735. 

Figure9.6 Typical luminescenceintensityversustimetrajectories of a single CdTe QD (4.6 nm) embedded in a PVA (a) and a trehalose (b) matrix dispersed on a cover glass surface at room temperature. The excitation intensity was 1.7 kW cm and the integration time was 200 ms bin ...

The effect of physical aging on the crystallization state and water vapor sorption behavior of amorphous non-solvated trehalose was studied [91]. It was found that annealing the amorphous substance at temperatures below the glass transition temperature caused nucleation in the sample that served to decrease the onset temperature of crystallization upon subsequent heating. Physical aging caused a decrease in the rate and extent of water vapor adsorption at low relative humidities, but water sorption could serve to remove the effects of physical aging due to a volume expansion that took place in conjunction with the adsorption process. 

Liposomes can, generally speaking, only be frozen without damage if the suspension is frozen in a glass phase of water. This requires the addition of CPAs e. g. mannitol, dextran or trehalose, and quick freezing (e. g. 10 °C/min by LN2) [3.37], (page 363). 

Crowe and Crowe [3.39] proved that it is sufficient for certain liposomes, e. g. egg phosphatidyl-choline (DPPC), to be vitrified by trehalose or dextran during freezing and freeze drying. In trehalose the retention rate was almost 100 %, and in dextran more than 80 %. This did not apply to egg PC-liposomes Dextran as CPA alone led to an almost total loss of the CF-indicator, but addition of dextran into a trehalose solution (Fig. 3.20) also reduced the retention rate of CF substantially, e. g. from 90 % in a pure trehalose to approx. 45 % if trehalose and dextran were in equal amounts in the solution. Since T of dextran is approx. -10 °C and Tg- of trehalose is -30 to -32 °C, dextran should form a glass phase at much higher temperatures than trehalose. Therefore the stabilization of egg- PC with trehalose cannot be related with the vitrification. Crowe showd with IR spectroscopy that egg-PC freeze dried with 2 g trehalose/g lipid had almost the identical spectrographic characteristics as the hydrous lipid Trehalose molecules replaced the water molecules, and hydrogen... 

Table 1.6.1 Glass transition temperature Tg and crystallization temperature Tc for amorphous sucrose, trehalose, lactose, raffinose and amorphous sucrose in the presence of absorbed water...

Hinrichs et al. [1.150] compared inulin of various degrees of polymerization with trehalose as glass-forming agents. Inilin above a certain degree of polymerization, DPn/DPw > 5.5/6.0, and trehalose stabilize alkaline phosphatase equally well. The Tg and T values for inulin of <5.5/6.0 where higher than those for trehalose. 

Vaccines are mixed with trehalose solution and spray-dried to form microscopic glass-like spheres which are then suspended in an inert liquid. As such they are stable and the vaccine is only reactivated when the liquid is injected into the body where water dissolves out the trehalose and releases the vaccine. Roser s method allows mixtures of vaccine powders to be stored without risk of their reacting with one another, and they can even be injected together. 

Temperature-dependent pure dephasing rates of MbCO in three solvents show identical power law behavior at low temperatures. At intermediate temperatures there is a break in the power law arising from the solvent-influenced protein glass transition. Above this point the data in glassy trehalose are exponentially activated. The other solvents, which at elevated temperatures are liquids, have additional solvent viscosity-dependent contributions to the pure dephasing rate. 

Table 12.3 lists the glass transition temperatures for all of the naturally occurring gluco-disaccharides, i.e., disaccharides composed of two glucose units, and for sucrose. For trehalose, the value of 115 2°C is currently accepted as the exact Tg of anhydrous trehalose [51-55], although various Tg values have been... 

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