Effect of lyophilization on the structure and phase changes of PEGylated-bovine serum albumin

Calorimetric Study of Inulin as Cryo- and Lyoprotector of Bovine Plasma Proteins

“…Besides, Table 1 shows that Tg of the sample increases with increasing saccharide concentration. Similar results were found in the references [28,30]. This effect can be explained considering that sugar forms hydrogenbridge bonds with proteins reducing the available volume for the interaction with water molecules, so water become less effective as plasticizer with an increase in saccharide content [51].…”

“…Fig 4 shows the crystallization temperature (Tc) obtained from the intersection of the baseline and the tangent of the exothermic peak, and the crystallization enthalpy (Hc) estimated as the area under the peak for the different protective agents at different concentrations. The crystallization temperature of freeze-dried samples was found to depend on the molecular weight and the saccharide concentration [27,30]. Therefore, the results showed that the presence of inulin at the same concentration than the other saccharides further increases the Tc value of freeze-dried solutions.…”

“…The glass transition is often followed by crystallization of the solutes where the molecular mobility increases and the sample crystallizes increasing the rate of food spoilage [27,28,30]. Fig 4 shows the crystallization temperature (Tc) obtained from the intersection of the baseline and the tangent of the exothermic peak, and the crystallization enthalpy (Hc) estimated as the area under the peak for the different protective agents at different concentrations.…”

“…It is noteworthy that amorphous materials are stable in the glassy state below Tg, when the temperature is higher the viscosity decreases and thus the rate of chemical reactions increases and crystallization events occur, increasing the rate of deterioration during storage [22,25,[27][28][29]. Both transitions T´g and Tg are important parameters in the development of the freezedrying cycle because not only ensures the stability and quality of the product, but also allow to improve the efficiency of the manufacturing process [20,22,28,30].…”

Interaction of Globular Plasma Proteins with Water‐Soluble CdSe Quantum Dots

“…In the IR study of proteins, the position [48,49] of the amide I component bands indicates the type of secondary structure; the amide I peak for proteins containing predominantly a-helical structure appears in the range of 1648-1660 cm ) of the proteins in the absence and presence of QDs an intense band in the amide I region could be observed. The bands at 1653, 1659, and 1663 cm À1 (BSA, b-Lg, and HSA, respectively), mainly due to amide I, are characteristic of high a-helical content in the proteins [50,51] . After binding to the QDs, the intensity of the band at 1659 cm À1 decreased, indicating that the a-helical content in the proteins was reduced.…”