Adsorption of human albumin and fibrinogen onto heparin-like materials II. Desorption and exchange processes

Adsorption/desorption of human serum albumin on hydroxyapatite: a critical analysis of the Langmuir model.

“…In the absence of an adsorbing or desorbing surface, when buffer solution is injected into the cell containing an activity AO, the activity A(t) at the outlet is given by A(t) = Ao exp(-Qvt/V). [3] Excellent agreement is obtained between theoretical and experimental dilution curves (22), which shows that the dilution process and the counting technique are well and precisely controlled. Experimental curves related to dilution in the presence of the adsorbent are given in Fig.…”

“…However, on the time scale of the experiments, only a limited population of adsorbed molecules seems to be "exchangeable." In addition, when a protein solution in contact with a solid phase is suddenly replaced by buffer, generally only a small fraction of the adsorbed molecules are desorbed (3,5). Moreover, it has progressively been recognized that the irreversible aspects of these processes increase significantly with the mean contact time between the proteins and the adsorbing surface (6,7).…”

“…It exhibits both reversible and irreversible aspects, which often seem to be in mutual contradiction. For example, adsorbed proteins can be exchanged with similar or different proteins from the bulk solution (2)(3)(4)(5). However, on the time scale of the experiments, only a limited population of adsorbed molecules seems to be "exchangeable."…”

Kinetics of exchange processes in the adsorption of proteins on solid surfaces.

“…This interaction can then be followed by sequential, segmental, reptation-like adsorption of the molecule, in competition with the dynamic process of the formation and annihilation of links of previously adsorbed macromolecules. Finally, the diffusing molecules progressively replace those already adsorbed on the surface, completing the exchange process.Such processes have been observed for synthetic polymers (2) as well as for proteins (3,4) by means of radioactive labeling techniques. NevertHeless, and in spite of a great number of investigations, little is known about adsorption processes of macromolecules (5).…”

“…Such processes have been observed for synthetic polymers (2) as well as for proteins (3,4) by means of radioactive labeling techniques. NevertHeless, and in spite of a great number of investigations, little is known about adsorption processes of macromolecules (5).…”