This vol.Dl\e of Advances in Experinental ~dicine and Biology is based on an Arrerican Chemical Society SympositUII entitled: "Surface Chemistry of Biological Systems", which took place in New York on September 11-12, 1969. Thanks to the special photo offset process used by the publishers, the papers are appearing very soon after their presentation, and at a lower cost than usual. These advantages are appreciated by the scientific community. As the title of the vol.Dl\e indicates we have attempted to bring the scientific approach and techniques of surface chemistry to the complex problems of biological systems. Two previous sym posia in this field have been published, one in the Journal of Colloid and Interface Science (24:1-127, 1967) and the other in the Journal of General Physiology (52:187S-252S, 1968). The previous publication outlets, a chemical and a biological journal, help to emphasize the interdisciplinary nature of the material and also the appropriateness of the choice of Advances in Experinental Medicine and Biology for the C1.lr'rent symposium.

Inhalt
The Effect of the Modification of Protein Structure on the Properties of Proteins Spread and Adsorbed at the Air-Water Interface.- The Interaction of Calcium with Monolayers of Stearic and Oleic Acid.- Studies of Thermal Transitions of Phospholipids in Water: Effect of Chain Length and Polar Groups of Single Lipids and Mixtures.- The Physical State of Lipids of Biological Importance: Cholesteryl Esters, Cholesterol, Triglyceride.- The Effect of Hydrocarbon Configuration and Cholesterol on Interactions of Choline Phospholipids with Sulfatide.- Lipid-Polymer Interaction in Monolayers: Effect of Conformation of Poly-L-Lysine on Stearic Acid Monolayers.- Interactions of DNA with Positively Charged Monolayers.- The Effect of Modifiers on the Intrinsic Properties of Bilayer Lipid Membranes (BLM).- Asymmetric Phospholipid Membranes: Effect of pH and Ca2+.- Dissociation of Functional Markers in Bacterial Membranes.- RNA in the Cell Periphery.- Immunological Reactions Carried Out at a Liquid-Solid Interface with the Help of a Weak Electric Current.- Electrophoresis and Adsorption Studies of Proteins and Their Derivatives on Colloids and Cells.- Surface Chemical Features of the Blood Vessel Walls and of Synthetic Materials Exhibiting Thromboresistance.- Lipid-Protein Association in Lung Surfactant.- Absence of Lipoprotein in Pulmonary Surfactants.- Relation of Water Transport to Water Content in Swelling Biological Membranes.- Kinetic and Equilibrium Behavior of Simple Sugars in a Water-Butanol-Lipid System.- Use of Synthetic Membrane Models in the Study of Gastric Secretory Processes.- Properties of the Plasma Membrane of Amoeba.