Abstract
The influence of proteins (bovine serum albumin, BSA, and mouse γ-globulin, IgG) physically adsorbed or covalently attached via coupling with N-cyclohexyl-N′-(2-morpholinoethyl) carbodiimide methyl-p- toluenesulfonate, CMC, to the surface of activated carbon SCN (spherical carbon with nitrogen) on the mobility of interfacial water molecules was studied by means of 1H NMR spectroscopy with freezing-out of bulk water at 180<T<273 K. Relaxation processes in the interfacial non-freezing water were investigated measuring transverse time t2 of proton relaxation dependence on the presence of proteins and CMC. The distribution function of activation free energy of relaxation (with a maximum at 20-22 kJ/mol) was calculated for the protein-water-carbon systems using a regularization procedure and the relationships between t2 and the amounts of the interfacial water unfrozen at T<250 K assuming the Arrhenius-type dependence for t 2-1 on temperature. The state of unfrozen water in pores of SCN shows that the low temperature relaxation processes occur in narrow pores with half-width X<1.5 nm.
Original language | English |
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Pages (from-to) | 333-341 |
Number of pages | 9 |
Journal | Journal of Colloid and Interface Science |
Volume | 278 |
Issue number | 2 |
DOIs | |
Publication status | Published - Oct 15 2004 |
Keywords
- Activated carbon
- H NMR spectroscopy
- Microporosity
- Nonfreezable interfacial water
- Protein chemisorption
- Protein immobilization
- Surface properties
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Biomaterials
- Surfaces, Coatings and Films
- Colloid and Surface Chemistry