General concepts l Bound water: exists in the vicinity of solutes and other non-aqueous constituents, exhibit reduced mobility and properties differing significantly from “bulk water” in the same system and does not freeze at -40°C – Constitutional water: integral part of non-aqueous constituents l < 0.03% of total water l Interstitial regions of proteins; chemical hydrates – Vicinal water: Strongly interacts with specific hydrophilic sites by water-ion and water-dipole associations - l 0.5 ± 0.4 % of total water l Optimum overall stability at the Monolayer value – Multilayer water: occupies remaining first-layer sites and forms several layers around hydrophilic groups by w-w and w-s hydrogen bonds - l 3 ± 2 % of total water l Rates of reactions increaseGeneral concepts l Bound water: exists in the vicinity of solutes and other non-aqueous constituents, exhibit reduced mobility and properties differing significantly from “bulk water” in the same system and does not freeze at -40°C – Constitutional water: integral part of non-aqueous constituents l < 0.03% of total water l Interstitial regions of proteins; chemical hydrates – Vicinal water: Strongly interacts with specific hydrophilic sites by water-ion and water-dipole associations - l 0.5 ± 0.4 % of total water l Optimum overall stability at the Monolayer value – Multilayer water: occupies remaining first-layer sites and forms several layers around hydrophilic groups by w-w and w-s hydrogen bonds - l 3 ± 2 % of total water l Rates of reactions increase