ABSTRACT
I. Introduction 419 II. Behavior of Biomaterial at Interface 420
A. Liquid-liquid interface 420 B. Solid-liquid interface 421
III. Isothermal Titration Microcalorimetry-Direct Measurement o f the Adsorption Enthalpy 422
IV. Applications of ITC on the Biomaterial at Interface 423 A. Ion-exchange system 423 B. Immobilized metal ion affinity system 424 C. Salt concentration effects on the enthalpy of adsorption 427
V. Conclusion 430 References 431
I. INTRODUCTION
Biomaterials such as proteins, peptides, polynucleotides, and cells exhibit different behaviors at solid-liquid, liquid-liquid, and liquid-air interfaces. The characteristics associated with the behaviors are attributed to properties of the biomaterial, of the inter face, and of the microenvironment of the interface. Nevertheless, bioindustrial applications involving interfaces provide the impetus for understanding the behavior of biomaterials at interface. Examples of industrial applications involving the character istics of biomaterials at interface are numerous. For instance, the biocomparability of a material heavily relies on the extent of blood proteins, such as fibrinogen and albumin, as well as adsorption on the material surface. The resolution of the protein purification by chromatography is ascribed to the adsorption/desorption of the proteins at the interface. Other applications involving enzyme or cell immobilization for reactions or water treatment contain biomaterial at interface. Therefore further understanding of the interaction between the biomaterial and the interface is highly desired.
