Biomacromolecule hydration

Fujita K, Macfarlane DR, Forsyth M et al (2007) Solubility and stability of cytochrome c in hydrated ionic liquids effect of oxo acid residues and kosmotropicity. Biomacromolecules 8 2080-2086... 

The solvent entropy is considered to be the thermodynamic contribution of the hydrophobic effect, which is primarily the driving force that folds biomacromolecules into compact structures. Hydration/solvation is an important problem in simulation of biomacromolecules since all biomacromolecules interact with water/aqueous solvents and the sequestering of nonpolar groups away from water gives rise to the hydrophobic effect. A simple relationship to describe the free energy for hydrating/solvating a macromolecule is... 

Figure 4.4 Digital images of POSS-PEG TPU with 1.0 wt% silver nitrate loading a) cast film and b) an e-spun fibrous mat made from 20 wt% dimethylformamide, which varied i) before and ii) after hydration. The scale bar represents 1 cm. Reproduced with permission from J. Wu, S. Hou, D. Ren and P.T. Mather, Biomacromolecules, 2009,10, 2686. 2009, American Chemical Society [49]...

Saito Y., Kumagai H., Wada M., Kuga S., Thermally reversible hydration of P-chitin, Biomacromolecules, 3(3), 2002, 407-410. 

Zhai, M. L., Kudoh, H., Wu, G. Z. et al. 2004b. Laser photolysis of carboxymethylated chitin derivatives in aqueous solution. Part 1. Formation of hydrated electron and a long-lived radical. Biomacromolecules 5 453-457. 

It is possible to explain the described regularities in changes of the spectral characteristics of water on rehydration of cells as follows. If the amounts of water in cells do not exceed a certain critical value, then water in dehydrated cells is localized mainly in cellular membranes (around protein molecules and other charged functionalities) and hydration shells of organelles and biomacromolecules. Such water (a portion of protons from this water) has a low value of the chemical shift characteristic for water molecules not participating in the hydrogen bonds as proton donors. 

Calucci, L., Galleschi, L., Geppi, M., and MoUica, G. 2004. Structure and dynamics of flour by solid state NMR Effects of hydration and wheat aging. Biomacromolecules 5 1536-1544. 

G.P. Holland, J.E. Jenkins, M.S. Creager, R.V. Lewis, J.L. Yarger, Solid-state NMR investigation of major and minor ampuUate spider sHk in the native and hydrated states. Biomacromolecules 9 (2008) 651-657. 

Control of the Sample Environment High-vacuum conditions or constant inert gas flow are necessary for studying intrinsic relaxation phenomena in hygroscopic materials. A chemically inert atmosphere is also desirable in studies of polymer solutions, biomacromolecules, and other biological substances, where precise control of the hydration levels is vital. In isothermal scans fluctuations of the sample temperature should be as small as possible (below 0.1 K), such fluctuations are usually controlled by most commercial temperature stabilization/regulation systems (see Section 6.4.1.2). The same recommendation applies for the heating rates typically used in nonisothermal dielectric techniques. 

Crouzier T, Picart C (2009) Ion pairing and hydration in polyelectrolyte multilayer films containing polysaccharides. Biomacromolecules 10 433-442... 

Astley OM, Donald AM. A smaU-angle X-ray seattering study of the effect of hydration on the microstructure of flax fibers. Biomacromolecules 2001 2 672-680. 

It is believed that using fibrin as a cell-deliveiy vehicle is limited by fibrin s low mechanical properties and low hydration capacity (Lee and Mooney, 2001). For this reason, efforts were made to add biomacromolecules to the fibrin gel to improve its biocompatibility. Yang et al. (2011) report the s5mthesis and potential applications of hybrid molecules composed of fibrinogen coupled to the reducing ends of short-chain hyaluronic acids (sHAs) by reductive amination (Fig. 16.9). 

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